Patent Publication Number: US-2022218981-A1

Title: Systems and methods for a transcranial electrical stimulation device

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 17/259,506, filed Jan. 1, 2021, which is a national stage application of International Application No. PCT/US2020/0321775, filed May 8, 2020, which claims the benefit of and priority to U.S. Provisional Patent Application No. 62/845,834, filed May 9, 2019, the entire contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to the field of transcranial electrical stimulation, and more specifically to systems and methods of transcranial electrical stimulation devices. 
     BACKGROUND 
     Transcranial direct current stimulation (tDCS), a type of non-invasive neurostimulation, can deliver a low level of current to the brain through electrodes placed on a head. The level of current delivered by tDCS can facilitate the hyperpolarization or depolarization of neurons in the brain. A tDCS device can be a portable device that implements transcranial direct current stimulation to a head of a user. However, tDCS devices can suffer from issues relating to bulky components and lack of adaptability with various head sizes of different users. 
     SUMMARY 
     The systems and methods of the present disclosure relate to a compact and lightweight transcranial electrical stimulation device which can adapt to head sizes of different users. According to an aspect of the present disclosure, the transcranial electrical stimulation device includes a base. The base includes a center portion, a first end portion, a second end portion, and a first surface extending along the first end portion, the center portion, and the second end portion. The first end portion is connected to the center portion. The first end portion is angled relative to the center portion. The second end portion is opposite the first end portion and connected to the center portion. The second end portion is angled relative to the center portion. The first surface extends along the first end portion, the center portion, and the second end portion. The transcranial electrical stimulation device includes a first electrode attached to the first end portion and on the first surface. The first electrode includes a first conductive cup. The first electrode includes a first post attached to the first conductive cup and the first end portion. The first post includes a flexible material to allow the first conductive cup to bend about the first post. The transcranial electrical stimulation device includes a second electrode attached to the second end portion and on the first surface. The second electrode includes a second conductive cup. The second electrode includes a second post attached to the first conductive cup and the second end portion. The second post includes a flexible material to allow the second conductive cup to bend about the second post. 
     In some embodiments, the first post spaces the first conductive cup from the first surface by a clearance distance, the clearance distance greater than or equal to 0.25 centimeters and less than or equal to 2 centimeters. 
     In some embodiments, the first post spaces the first conductive cup from the first surface by a clearance distance, a ratio of the clearance distance to a thickness of the base is greater than or equal to 0.2 to 1 and less than or equal to 1.2 to 1. 
     In some embodiments, a first diameter of the first conductive cup is greater than a first width of the first end portion. A second diameter of the second conductive cup can be greater than a second width of the second end portion. 
     In some embodiments, the first conductive cup and the second conductive cup contour to a head of a user. 
     In some embodiments, the transcranial electrical stimulation device includes a strap extending from the first end portion to the second end portion. The strap can be configured to secure the first electrode and the second electrode to a head of a user. The strap can be adjustable. 
     In some embodiments, the transcranial electrical stimulation device includes a pin coupled with the first post, and a pin receiver coupled with the first end portion, the pin receiver configured to receive the pin to secure a conductive portion of the first conductive cup to a non-conductive portion of the first conductive cup, the conductive portion coupled with the first post. 
     In some embodiments, the pin receives current from a power supply and provides the current to the conductive portion of the first conductive cup. 
     In some embodiments, the transcranial electrical stimulation device includes a charging port disposed on the first surface of the base and on the center portion of the base. 
     In some embodiments, the transcranial electrical stimulation device includes a second surface of the base extending along the first end portion, the center portion, and the second end portion. The transcranial electrical stimulation device can include a power button disposed on the second surface and on the center portion of the base. 
     In some embodiments, the transcranial electrical stimulation device includes a second surface of the base extending along the first end portion, the center portion, and the second end portion. The transcranial electrical stimulation device can include a light emitting diode (“LED”) disposed on the second surface and on the center portion of the base. 
     In some embodiments, the first electrode is removably attached to the first end portion. The second electrode can be removably attached to the second end portion. 
     In some embodiments, the first conductive cup comprises a first raised edge and the second conductive cup comprises a second raised edge. 
     In some embodiments, a method for engaging in transcranial electrical stimulation includes securing a transcranial electrical stimulation device to a head of a user. The method can include initiating, by a control circuit, a stimulation session wherein the control circuit couples a power supply to a first electrode and a second electrode to enter a powered state. The method can include increasing, by the control circuit, a current to a first current level over a first period of time, wherein the current flows through the head of the user from a first electrode of the transcranial electrical stimulation device to a second electrode of the transcranial electrical stimulation device. The method can include maintaining, by the control circuit, the current at the first current level over a second period of time. The method can include decreasing, by the control circuit, responsive to a termination condition, the current to second current level over a third period of time. The method can include terminating, by the control circuit, the stimulation session wherein the control circuit decouples the power supply to the first electrode and the second electrode to exit the powered state. 
     In some embodiments, the transcranial electrical stimulation device comprises a LED. The method can include confirming, by the LED through visual cues, that the transcranial electrical stimulation device is properly secured to the head of the user. Initiating the stimulation session can occur responsive to a confirmation that the transcranial electrical stimulation device is properly secured. 
     In some embodiments, the transcranial electrical stimulation device comprises a LED. The method can include confirming, by the LED through visual cues, that the transcranial electrical stimulation device is improperly secured to the head of the user. The method can include terminating the stimulation session. Terminating the stimulation session can include stopping a flow of current through the head of the user from the first electrode of the transcranial electrical stimulation device to the second electrode of the transcranial electrical stimulation device. Terminating the stimulation session can include exiting the powered state. 
     In some embodiments, the transcranial electrical stimulation device comprises a power button. The method includes initiating, by activating a power button, the stimulation session wherein the control circuit couples the power supply to the first electrode and the second electrode to enter the powered state. The method includes terminating, by activating a power button, the stimulation session wherein the control circuit decouples the power supply to the first electrode and the second electrode to exit the powered state. 
     In some embodiments, the termination condition is a predetermined length of time. The termination condition can be an interrupted stimulation session. The termination condition can be a resistance exceeding a threshold. 
     In some embodiments, the method can include signaling, by an audio component, an operational state of the transcranial electrical stimulation device. The method can include signaling, by a LED, an operational state of the transcranial electrical stimulation device. 
     In some embodiments, securing the transcranial electrical stimulation device to the head of the user includes adjusting a first position of the first electrode of the transcranial electrical stimulation device and a second position of the second electrode of the transcranial electrical stimulation device. 
     In some embodiments, a method for engaging in transcranial electrical stimulation comprising securing a transcranial electrical stimulation device to a head of a user in a first orientation such that a first electrode is electrically coupled and positioned proximate to a first surface region of the head and a second electrode is electrically coupled and positioned proximate to a second surface region of the head. The method includes initiating, via a control circuit, a stimulation session. The control circuit couples a power supply to the first electrode and the second electrode to enter a first powered state, increases a current to a first current level over a first period of time, wherein the current flows from the first electrode through the head of the user in a first direction to the second electrode, maintains the current at the first current level over a second period of time, decreases, responsive to a termination condition, the current to a second current level over a third period of time, and terminates the stimulation session wherein the control circuit decouples the power supply to the first electrode and the second electrode to exit the powered state. The method also includes removing the transcranial electrical stimulation device from the head of the user. The method further includes securing the transcranial electrical stimulation device to the head of the user in a second orientation such that the first electrode is electrically coupled and positioned proximate to the second surface region of the head and the second electrode is electrically coupled and positioned proximate to the first surface region of the head and initiating, via the control circuit, a second stimulation session. The control circuit couples the power supply to the first electrode and the second electrode to enter a second powered state, increases the current to the first current level over a third period of time, wherein the current flows from the first electrode through the head of the user in a second direction to the second electrode, maintains the current at the first current level over a fourth period of time, and decreases, responsive to a termination condition, the current to the second current level over a fifth period of time, and terminates the stimulation session, wherein the control circuit decouples the power supply to the first electrode and the second electrode to exit the powered state. The method further includes removing the transcranial electrical stimulation device from the head of the user. 
     Some or all of the systems, components, and subcomponents of the present disclosure can be single-use or disposable. Also some or all of the systems, components, and subcomponents of the present disclosure can be made of a unitary construction (formed from a single piece of metal, plastic, or other material) or unitary modular construction (plurality of components and/or subcomponents permanently connected by standard means, such as welding or soldering), or of modular construction (plurality of components and/or subcomponents removably connected by standard means, such as threading or snap-fitting). 
     These and other features of various embodiments can be understood from a review of the following detailed description in conjunction with the accompanying drawings. 
     It is to be understood that both the foregoing general description and the following detailed description are explanatory and are not restrictive of the present disclosure, as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view of an embodiment of a transcranial electrical stimulation device. 
         FIG. 2A  illustrates a perspective view of an embodiment of a transcranial electrical stimulation device. 
         FIG. 2B  is a perspective view of the transcranial electrical stimulation device shown in  FIG. 2A . 
         FIG. 2C  is a front view of the transcranial electrical stimulation device shown in  FIG. 2A . 
         FIG. 2D  is a rear view of the transcranial electrical stimulation device shown in  FIG. 2A . 
         FIG. 2E  is a left side view of the transcranial electrical stimulation device shown in  FIG. 2A . 
         FIG. 2F  is a right side view of the transcranial electrical stimulation device shown in  FIG. 2A . 
         FIG. 2G  is a bottom view of the transcranial electrical stimulation device shown in  FIG. 2A . 
         FIG. 2H  is a top view of the transcranial electrical stimulation device shown in  FIG. 2A  in a first orientation. 
         FIG. 2I  is a top view of the transcranial electrical stimulation device shown in  FIG. 2A  in a second orientation. 
         FIG. 3  illustrates a perspective view of an embodiment of a transcranial electrical stimulation device. 
         FIG. 4  illustrates a perspective view of an embodiment of a transcranial electrical stimulation device. 
         FIG. 5  illustrates a perspective view of an embodiment of a transcranial electrical stimulation device without electrodes. 
         FIG. 6  illustrates a perspective view of an embodiment of an electrode of a transcranial electrical stimulation device. 
         FIG. 7  illustrates a perspective view of an embodiment of a transcranial electrical stimulation device interior. 
         FIG. 8  illustrates an exploded view of an embodiment of a transcranial electrical stimulation device. 
         FIG. 9  illustrates a block diagram of an embodiment of a sponge. 
         FIG. 10  illustrates a block diagram of an embodiment of a transcranial electrical stimulation device. 
         FIG. 11  illustrates a flow diagram of an example method for engaging in transcranial electrical stimulation. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description and the appended drawings describe and illustrate various transcranial electrical stimulation device systems and methods. The description and drawings are provided to enable one of skill in the art to make and use one or more transcranial electrical stimulation device systems and/or practice one or more methods. They are not intended to limit the scope of the claims in any manner. 
     The present solution provides devices, systems, and methods for improved transcranial electrical stimulation by using a compact and lightweight device that can allow a greater variety of users to more comfortably operate and wear the device for longer periods of time. In existing solutions, transcranial electrical stimulation devices may be bulky, non-portable, and difficult to operate, resulting in the overall lack of use and adoption of transcranial direct current stimulation as a technique to stimulate neuronal activity. The present solution can use a more ergonomic form factor having a size and weight low enough to be secured to the head of the user with a more comfortable securing device, such as a strap, and can use electrodes and components that couple the electrodes with a base of the device that have sufficient flexibility to conform to a variety of head shapes and sufficient resilience to maintain proper contact with users&#39; heads during the course of stimulation. The present solution can enable the device to be operated in a first orientation (as shown in  FIG. 2H ) in which a first stimulation is performed, such as a first stimulation in which current flows from a first electrode into the head of the user, and into a second electrode, and a second orientation (as shown in  FIG. 2I ) (e.g., by flipping the device upside down or rotating the device 180 degrees about the axis extending through the end portions and the center portion) in which a second stimulation is performed in which the current can flow in an opposite direction through the head, enabling a greater variety of stimulation to be provided using the same device. In some embodiments, a transcranial electrical stimulation device includes a base. The base includes a center portion, a first end portion, a second end portion, and a first surface extending along the first end portion, the center portion, and the second end portion. The first end portion is connected to the center portion. The first end portion is angled relative to the center portion. The second end portion is opposite the first end portion and connected to the center portion. The second end portion is angled relative to the center portion. The first surface extends along the first end portion, the center portion, and the second end portion. The transcranial electrical stimulation device includes a first electrode attached to the first end portion and on the first surface. The first electrode includes a first conductive cup. The first electrode includes a first post attached to the first conductive cup and the first end portion. The first post includes a flexible material to allow the first conductive cup to bend about the first post. The transcranial electrical stimulation device includes a second electrode attached to the second end portion and on the first surface. The second electrode includes a second conductive cup. The second electrode includes a second post attached to the first conductive cup and the second end portion. The second post includes a flexible material to allow the second conductive cup to bend about the second post. The first electrode can be an anode and the second electrode can be a cathode. Electrical current can flow from the anode to the cathode. 
     A method for engaging in transcranial electrical stimulation can include securing a transcranial electrical stimulation device to a head of a user. The method can include initiating, by a control circuit, a stimulation session wherein the control circuit couples a power supply to a first electrode and a second electrode to enter a powered state. The method can include increasing, by the control circuit, a current to a first current level over a first period of time, wherein the current flows through the head of the user from a first electrode (i.e., anode) of the transcranial electrical stimulation device to a second electrode (i.e., cathode) of the transcranial electrical stimulation device. The method can include maintaining, by the control circuit, the current at the first current level over a second period of time. The method can include decreasing, by the control circuit, responsive to a termination condition, the current to second current level over a third period of time. The method can include terminating, by the control circuit, the stimulation session wherein the control circuit decouples the power supply to the first electrode and the second electrode to exit the powered state. 
     Referring to  FIG. 1 , a perspective view of an embodiment of a transcranial electrical stimulation device  100  is shown. The transcranial electrical stimulation device  100  can be a lightweight (e.g., less than 100 grams, less than 75 grams, or less than 50 grams) device adaptable to users with various head sizes. The transcranial electrical stimulation device  100  can include an external power supply and be portable. The transcranial electrical stimulation device  100  can have an operating temperature of 0° C. to 50° C. The transcranial electrical stimulation device  100  can be used for transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), transcranial electrical stimulation (tES), transcranial random noise stimulation (tRNS), or cranial electrotherapy stimulation (CES), among others. The transcranial electrical stimulation device  100  can target the dorsolateral prefrontal cortex (DLPFC), the rostrolateral prefrontal cortex (RLPFC), the motor cortex or other regions of a user. DLPFC exists both on the right and the left side of the brain and is a subsection of the prefrontal cortex. DLPFC has been ascribed control or involvement in a variety of higher order cognitive functions such as cognition, attention, working memory, and decision-making as well as implicated in emotional, social, motivational and perceptual processes. 
     The transcranial electrical stimulation device  100  can include a base  102 . The base  102  can be composed of plastic (e.g., polyethylene terephthalate, high-density polyethylene, polyvinyl chloride, low-density polyethylene, polypropylene, polystyrene, Styrofoam, polycarbonate, polyactide, acrylic, acrylonitrile butadiene, styrene, fiberglass, or nylon). The base  102  can include a center portion  104 , a first end portion  106 , and a second end portion  108 . The base  102  can include a first surface  109  extending along the first end portion  106 , the center portion  104 , and the second end portion  108 . The base  102  can include attachment points for the electrodes (described herein) and locations for various components (e.g., power button, light emitting diode, connection port described herein). The base  102  can be composed of an electrical insulator. The base  102  is or can include a housing to hold various components (e.g., internal circuitry, sensors, wires). The base  102  can have an exterior component that defines an interior of the base  102 . 
     In some embodiments, the exposed surfaces of the center portion  104 , the first end portion  106 , and the second end portion  108  are free of any extensions or protrusions that restrict the device  100  from being worn by a user in a first orientation and a second orientation. 
     The center portion  104  can be connected to the first end portion  106  and the second end portion  108 . The center portion  104  can include locations for various components (e.g., power button, light emitting diode, connection port described herein). The center portion  104  can be composed of plastic (e.g., polyethylene terephthalate, high-density polyethylene, polyvinyl chloride, low-density polyethylene, polypropylene, polystyrene, Styrofoam, polycarbonate, polyactide, acrylic, acrylonitrile butadiene, styrene, fiberglass, or nylon). The center portion  104  can define a third plane  134 . The center portion  104  can be continuously connected to the first end portion  106 . The center portion  104  can be continuously connected to the second end portion  108 . The center portion  104  can surfaces center portion  104 . For example, the center portion  104  can define a first surface  109 . The center portion  104  can define a second surface  418  described herein. The first surface  109  can be substantially perpendicular to the second surface  418 . 
     The first end portion  106  can be connected to the center portion  104 . The first end portion  106  can be angled relative to the center portion  104 . For example, a first plane  130  defined by the first end portion  106  can intersect the third plane  134  defined by the center portion  104  at a first angle  138 . The first angle  138  can be greater than 90° (e.g., greater than 100°, greater than 135°, or greater than 160°). A first electrode  110  can be attached to the first end portion  106  and on the first surface  109 . The first end portion  106  can be curved relative to the center portion  104 . The curve can be parabolic. 
     The first electrode  110  can include a first conductive cup  112  and a first post  114 . The first electrode  110  can be composed of a conductor (e.g., conductive silicone, conductive rubber). The first electrode  110  can be electrically connected to the second electrode  120  through the base  102 . For example, the base  102  can include circuitry in the interior of the base  102  connecting the first electrode  110  to the second electrode  120 . 
     The first conductive cup  112  can have a concave shape. The first conductive cup  112  can be composed of a conductor (e.g., conductive silicone, conductive rubber). The first conductive cup  112  can be composed of a conductive silicone compound elastomer. The first conductive cup  112  can be composed of conductive silicon with carbon. The first conductive cup  112  can be composed of a flexible material to bend and conform to the head of the user. The first conductive cup  112  can have a conductive area of 22.3 cm 2 . The first conductive cup  112  can be connected to the first post  114 . The first conductive cup  112  can be electrically connected to the first post  114 . The first conductive cup  112  can include a non-conductive outer material (e.g., rubber, silicone). 
     The first post  114  can be attached to the first conductive cup  112  and the first end portion  106 . The first post  114  can be composed of a flexible material to allow the first conductive cup  112  to bend about the first post  114 . The first post  114  can have a rectangular prism shape. The first post  114  can have a cylindrical shape. The first post  114  can connect to the first conductive cup  112  through a locking mechanism (e.g., bar lock, pin lock, clip). The first post  114  can be molded into the first conductive cup  112 . The first post  114  can be composed of a stiff material attached to a ball bearing. The first post  114  can pivot about the ball bearing. 
     The first post  114  can provide clearance for the first electrode  110  and the first surface  109 . The first post  114  can space the first conductive cup  112  from the first surface  109  by a clearance distance  150 . The clearance distance  150  can be greater than or equal to 0.25 centimeters and less than or equal to 2 centimeters. For example, the clearance distance  150  can be 0.5 centimeters. A ratio of the clearance distance to a thickness of the base is greater than or equal to 0.2 to 1 and less than or equal to 1.2 to 1. For example, the ratio of the clearance distance  150  to the thickness of the base can be 0.5 to 1. The thickness of the base member can be a base thickness  152 . 
     The second end portion  108  can be connected to the center portion  104 . The second end portion  108  can be angled relative to the center portion  104 . For example, a second plane  132  defined by the second end portion  108  can intersect a third plane  134  defined by the center portion  104  at a second angle  140 . The second angle  140  can be greater than 90° (e.g., 100°, 120°, 135°, 150°, 160°). A second electrode  120  can be attached to the second end portion  108  and on the first surface  109 . The second end portion  108  can be curved relative to the center portion  104 . The curve can be parabolic. 
     The second electrode  120  can include a second conductive cup  122  and a second post  124 . The second electrode  120  can be composed of a conductor (e.g., conductive silicone, conductive rubber). The second electrode  120  can be electrically connected to the second electrode  120  through the base  102 . For example, the base  120  can include circuitry in the interior of the base  102  connecting the second electrode  120  to the first electrode  110 . 
     The second conductive cup  122  can have a concave shape. The second conductive cup  122  can be composed of a conductor (e.g., conductive silicone). The second conductive cup  122  can be composed of a conductive silicone compound elastomer. The second conductive cup  122  can be composed of conductive silicon with carbon. The second conductive cup  122  can be composed of a flexible material to bend and conform to the head of the user. The second conductive cup  122  can have a conductive area of 22.3 cm 2 . The second conductive cup  122  can be connected to the second post  124 . The second conductive cup  122  can be electrically connected to the second post  124 . The second conductive cup  122  can include a non-conductive outer material (e.g., rubber, silicone). 
     The second post  124  can be attached to the second conductive cup  122  and the second end portion  108 . The second post  124  can be composed of a flexible material to allow the second conductive cup  122  to bend about the second post  124 . The second post  124  can have a rectangular prism shape. The second post  124  can have a cylindrical shape. The second post  124  can connect to the second conductive cup  122  through a locking mechanism (e.g., bar lock, pin lock, clip). The second post  124  can be molded into the second conductive cup  122 . The second post  124  can be composed of a stiff material attached to a ball bearing. The second post  124  can pivot about the ball bearing. The second post  124  can provide clearance for the first electrode  110  and the first surface  109 . 
     The second post  124  can provide clearance for the second electrode  112  and the first surface  109 . The second post  124  can space the second conductive cup  122  from the first surface  109  by a clearance distance  150 . The clearance distance  150  can be greater than or equal to 0.25 centimeters and less than or equal to 2 centimeters. For example, the clearance distance  150  can be 0.5 centimeters. A ratio of the clearance distance to a thickness of the base is greater than or equal to 0.2 to 1 and less than or equal to 1.2 to 1. For example, the ratio of the clearance distance  150  to the thickness of the base can be 0.5 to 1. The thickness of the base can be a base thickness  152 . 
     As shown in  FIG. 1 , the first post and the corresponding first electrode and the second post and the corresponding second electrode extend outwardly from the first surface  109 . The device is free of any components or extensions that extend outwardly from the first surface  109  or the center portion  104  of the device that would restrict a wearer of the device from wearing the device  100  in either a first orientation or a second orientation opposite the first orientation. 
     Referring to  FIG. 2A-2I ,  FIG. 2A  shows a perspective view of an embodiment of a transcranial electrical stimulation device  100 . A first diameter  202  defined by the first conductive cup  112  can be greater than a first width  204  defined by the first end portion  106 . The first diameter  202  can be between 4 cm and 7 cm, for example, 5.3 cm. The first width  204  can be between 2 and 4 cm, for example, 3 cm. A second diameter  212  defined by the second conductive cup  122  can be greater than a second width  214  defined by the second end portion  108 . The second diameter  212  can be between 4 cm and 7 cm, for example, 5.3 cm. The second width  214  can be between 2 and 4 cm, for example, 3 cm. In some embodiments, the first diameter  202  defined by the first conductive cup  112  can be less than or equal to the first width  204  defined by the first end portion  106 . The second diameter  212  defined by the second conductive cup  122  can be less than or equal to the second width  214  defined by the second end portion  108 . A third width  216  defined by the center portion  104  can be between 3 cm and 5 cm, for example, 4 cm. The first diameter  202  and the second diameter  212  can be greater than the third width  216 . 
     The first conductive cup  112  can define a first center  220  of the first conductive cup  112  (additionally depicted in  FIG. 3 ). The second conductive cup  122  can define a second center  222  (additionally depicted in  FIG. 3 ). The base  102  can include a first point  230  on the first end portion  106  and a second point  232  on the second end portion  108 . The distance between the first point  230  on the first end portion  106  and the second point  232  on the second end portion  108  can define a base length  234 . The base length  234  can be between 10 cm and 15 cm, for example, 13.6 cm. The distance between the first center  220  of the first conductive cup  112  and the second center  222  of the second conductive cup  122  can define an electrode spacing  224 . The electrode spacing  224  can be between 5 cm and 10 cm, for example, 7 cm. The base length  234  can be greater than or equal to the electrode spacing  224 . 
     Referring to  FIG. 3 , a perspective view of an embodiment of a transcranial electrical stimulation device  100  is shown. The transcranial electrical stimulation device  100  can include a strap  302 . The strap  302  can be attached to the base  102  at the first end portion  106  and at the second end portion  108 . The strap  302  can be composed of elastic materials (e.g., rubber, elastic fibers, spandex, elastane, polyester, cotton). The strap  302  can include hook-and-loop fasteners to attach the strap  302  to the first end portion  106  and to the second end portion  108 . The strap  302  can extend from the first end portion  106  to the second end portion  108 . The strap  302  can be configured to secure the first electrode  110  and the second electrode  120  to a head of a user. The strap  302  can be adjustable. The strap can be adjusted on the head of the user to allow the first electrode  110  and the second electrode  120  to contact the head of the user. The first conductive cup  112  and the second conductive cup  122  can contour to the head of the user. Contouring to the head of the user can include the surfaces of the first conductive cup  112  and the surfaces of the second conductive cup  122  lying flush against the head of the user. The first center  220  of the first conductive cup  112  and the second center  222  of the second conductive cup  122  is shown. The first conductive cup  112  can define a first center  220  of the first conductive cup  112 . The second conductive cup  122  can define a second center  222 . 
     In some embodiments, the strap  302  can include a retaining device. The retaining device can wrap partially or entirely around the head of a user. The retaining device can be composed of plastic. The strap  302  can include a headband. The strap  302  can be composed of synthetic fibers (e.g., nylon, spun polyester, textured polyester, polypropylene, among others). The strap  302  can be composed of natural materials (e.g. hemp, leather, cotton, jute, among others). The strap  302  can include a retaining device that fits most or all head sizes. 
     Referring to  FIG. 4 , a perspective view of an embodiment of a transcranial electrical stimulation device  100  is shown. The transcranial electrical stimulation device  100  can include a charging port  408  disposed on the first surface  109  of the base  102 . The charging port  408  can be disposed on the center portion  104  of the base  102 . The charging port  408  can be a universal serial bus (USB) port (e.g., USB-B, USB-A, micro USB, mini USB, USB Type C, among others). A cover  540  (described herein) can be removably attached to the charging port  408  to provide protection to the charging port  408  when the transcranial electrical stimulation device  100  is not charging. A fourth width  432  defined by the center portion  104  can be between 1 cm and 2 cm, for example, 1.1 cm. 
     The charging port  408  of the transcranial electrical stimulation device  100  can be configured to also be a communication port through which data from the device  100  can be communicated with one or more other computing devices, such as a mobile phone, a smartphone, a tablet, or other computing device. In some embodiments, the transcranial electrical stimulation device  100  can include a separate communication port through which data from the device  100  can be communicated with one or more other computing devices. In some embodiments, the communication port can be a wireless communication port, such as a port that can communicate with other computing devices via BLUETOOTH, Wi-Fi, cellular, or any other wireless connection. 
     The transcranial electrical stimulation device  100  can be configured to include a processor and memory for storing data. The data can include user profile information of a user of the device  100 , for instance, data corresponding to certain settings according to which to conduct the stimulation session. The data can also include any information corresponding to when a session was initiated, terminated, or interrupted, among others. The information can be stored in the memory of the device  100 . The information can then be transmitted to one or more computing devices via the communication port of the device  100 . 
     In some embodiments, the device can be configured to allow a user to select a particular stimulation session type from a plurality of different stimulation session types. The different stimulation session types can be preset and pre-stored in the memory of the device. The different session types can include different stimulation parameters, including different lengths of time of the session, different amplitudes of the current including one or more current amplitude patterns over the duration of the session, among others. The current amplitude patterns can include a ramp up pattern, a ramp down pattern and any other patterns during the course of the stimulation session. The device can include a button or other input selection component that allows the user to select from a particular stimulation session type from the plurality of different stimulation session types. In some embodiments, the amplitude of the current can be 0.1 mA, 0.5 mA, 1 mA, 1.1 mA, 1.2 mA, 1.3 mA, 1.4 mA, 1.5 mA, 1.6 mA, 1.7 mA, 1.8 mA, 1.9 mA, 2 mA, 2.1 mA, 2.2 mA, 2.3 mA, 2.4 mA, 2.5 mA, 2.6 mA, 2.7 mA, 2.8 mA, 2.9 mA, 3 mA, 3.1 mA, 3.2 mA, 3.3 mA, 3.4 mA, 3.5 mA, 3.6 mA, 3.7 mA, 3.8 mA, 3.9 mA, 4 mA, or 5 mA. In some embodiments, the length of the session can vary between 5 minutes to 60 minutes. In particular, the length of the session can be 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, 16 minutes, 17 minutes, 18 minutes, 19 minutes, 20 minutes, 21 minutes, 22 minutes, 23 minutes, 24 minutes, 25 minutes, 26 minutes, 27 minutes, 28 minutes, 29 minutes, 30 minutes, 31 minutes, 32 minutes, 33 minutes, 34 minutes, 35 minutes, 36 minutes, 37 minutes, 38 minutes, 39 minutes, 40 minutes, 41 minutes, 42 minutes, 43 minutes, 44 minutes, 45 minutes, 46 minutes, 47 minutes, 48 minutes, 49 minutes, 50 minutes, 51 minutes, 52 minutes, 53 minutes, 54 minutes, 55 minutes, 56 minutes, 57 minutes, 58 minutes, 59 minutes, or 60 minutes. 
     As described herein, the device is configured to be operated in two orientations. In some embodiments, the plurality of different stimulation session types a user can select from can vary based on the orientation in which the device is worn by the user. For instance, if the device is worn in the first orientation (as shown in  FIG. 2H ), stimulation session types  1 ,  2  and  3  may be available for selection. If the device is worn in the second orientation (as shown in  FIG. 2I ), stimulation session types  1 ,  4  and  5  may be available for selection. The device can include one or more sensors that allow the processor to determine the orientation in which the device is worn and therefore, can be able to determine which stimulation session type to provide to the electrodes based on the orientation in which the device is worn. 
     The transcranial electrical stimulation device  100  can include a second surface  418 . The second surface  418  can extend along the first end portion  106 , the center portion  102  and the second end portion  108 . The transcranial electrical stimulation device  100  can include a power button  402 . The power button  402  can be disposed on the second surface  418 . The power button  402  can be disposed on the center portion  102  of the base  102 . In some embodiments, the button can be positioned anywhere on the device including the first end portion  106  or the second end portion  108 . 
     The transcranial electrical stimulation device  100  can include a light emitting diode (“LED”)  404 . The LED  404  can be disposed on the second surface  418 . The LED  404  can be disposed on the center portion  102  of the base  102 . The electrical connections of the LED  404  can be housed in the interior of the base  102 . The LED  404  can emit light of various colors, such as red, green and blue. The LED  404  can emit light to indicate a status of the transcranial electrical stimulation device  100 . The LED  404  can indicate battery supply or battery capacity of the transcranial electrical stimulation device  100 . 
     The transcranial electrical stimulation device  100  can include a first strap engagement  420 . The first strap engagement  420  can be disposed on the first end portion  106 . The first strap engagement  420  can provide a geometry to removably attach the strap  302  to the transcranial electrical stimulation device  100 . The first strap engagement  420  can define a deadeye geometry for the strap  302  to attach to the first strap engagement  420 . The first strap engagement  420  can be a handle for the strap  302  to attach to the first strap engagement  420 . The first strap engagement  420  can contact a hook-and-loop fastener of the strap  302 . 
     The transcranial electrical stimulation device  100  can include a second strap engagement  422 . The second strap engagement  422  can be disposed on the second end portion  108 . The second strap engagement  422  can provide a geometry to removably attach the strap  302  to the transcranial electrical stimulation device  100 . The second strap engagement  422  can define a deadeye geometry for the strap  302  to attach to the first strap engagement  420 . The second strap engagement  422  can be a handle for the strap  302  to attach to the second strap engagement  422 . The second strap engagement  422  can contact a hook-and-loop fastener of the strap  302 . 
     The first conductive cup  112  of the transcranial electrical stimulation device  100  can include a first raised edge  410 . The first raised edge  410  can provide a shallow wall for the concave shape of the first conductive cup  112 . The second conductive cup  122  of the transcranial electrical stimulation device  100  can include a second raised edge  412 . The second raised edge  412  can provide a shallow wall for the concave shape of the second conductive cup  122 . The first conductive cup  112  can hold a sponge  900  to directly contact the head of a user. The first conductive cup  112  can securely hold the sponge  900  to the head of the user. The second conductive cup  122  can hold a sponge  900  to directly contact the head of the user. The second conductive cup  122  can securely hold the sponge  900  to the head of the user. 
     Referring to  FIG. 5 , a perspective view of an embodiment of a transcranial electrical stimulation device  100  without electrodes is shown. The transcranial electrical stimulation device  100  is shown without the first electrode  110  and the second electrode  120 . The base  102  can include a first post socket  502 , a second post socket  512  and one or more holes  506 . 
     The transcranial electrical stimulation device  100  can include the first post socket  502 . The first post  114  can insert into the first post socket  502 . The first post socket  502  can receive the first post  114 . The first post socket  502  can include an attachment mechanism or locking mechanism (e.g., bar lock, pin lock  614  as described with reference to  FIG. 6 , clip). The first electrode  110  can be removably attached to the first end portion  106 . The first post  114  of the first electrode  110  can be removably attached to the first post socket  502  of the first end portion  106 . 
     The transcranial electrical stimulation device  100  can include the second post socket  512 . The second post  124  can insert into the second post socket  512 . The second post socket  512  can receive the second post  124 . The second post socket  512  can include an attachment mechanism or locking mechanism (e.g., bar lock, pin lock, clip). The second electrode  120  can be removably attached to the second end portion  108 . The second post  124  of the second electrode  120  can be removably attached to the second post socket  512  of the second end portion  108 . 
     The transcranial electrical stimulation device  100  can include one or more holes  506 . The one or more holes  506  can be disposed on the center portion  104 , first end portion  106 , or the second end portion  108 . The one or more holes  506  can be disposed on the first surface  109 . The one or more holes  506  can be threaded holes to allow a locking mechanism (e.g., screw) to hold a first exterior piece  530  to the second exterior piece  532 . The first surface  109  can define the first exterior piece  530 . The second surface  418  can define the second exterior piece  532 . 
     The charging port  408  of the transcranial electrical stimulation device  100  can include a cover  540 . The cover  540  can protect the charging port  408  from damage. The cover  540  can be attached to the base  102  of the transcranial electrical stimulation device  100 . The cover  540  can lay on top of the charging port  408 . The cover  540  can be removably attached to the base  102 . 
     Referring to  FIG. 6 , a perspective view of an embodiment of an electrode  600  of a transcranial electrical stimulation device  100 . The electrode  600  can include the first electrode  110  or the second electrode  120 . The electrode  600  can include a conductive cup  612 . The conductive cup can include the first conductive cup  112  or the second conductive cup  122 . The electrode  600  can include a pin lock  614  to secure the post  616  to a back-side cover  830 . The post  616  can be a conductive portion. The back-side cover  830  can be a non-conductive portion. The pin lock  614  can be composed of a conductive material. The electrode  600  can include a non-conductive cup  618 . The non-conductive cup can include a first non-conductive cup  812  or a second non-conductive cup  822 . Current can be provided via the pin lock  614  to the post  616 . Current can be provided via the post  616  to the conductive cup  612 . The pin lock  614  can secure the first conductive cup  112  to the base  102 . The pin lock  614  can secure the second conductive cup  122  to the base  102 . 
     Referring to  FIG. 7 , a perspective view of an embodiment of a transcranial electrical stimulation device  100  interior is shown. The transcranial electrical stimulation device  100  is shown without the first exterior piece  530 . The second exterior piece  532  of the base  102  is shown. The second exterior piece  532  includes one or more receiving holes  702 . The one or more receiving holes  702  can receive a locking mechanism (e.g., screw) to secure the first exterior piece  530  to the second exterior piece  532 . The one or more holes  702  can be threaded holes. The one or more holes  702  can be disposed on the surface of the second exterior piece  532 . The one or more holes  702  can be disposed on the interior surface of the base  102 . 
     The transcranial electrical stimulation device  100  can include a printed circuit board (PCB)  710 . The PCB  710  can include wired connections to the charging port  408 , the LED  404  and the power button  402 . The PCB  710  can include wired connections to the first electrode  110  and to the second electrode  112 . The PCB  710  can include wired connections to the pin lock  614 . The PCB  710  can include a control circuit  802  described in detail herein. The PCB  710  can include wired connections to an audio component  712  and a battery  714 . 
     The audio component  712  can include a component of the transcranial electrical stimulation device  100  that makes sounds to signal an operation state of the transcranial electrical stimulation device  100 . The audio component can include a piezoelectric buzzer. The audio component  712  can be controlled by a control circuit to signal different operational states or modes of the transcranial electrical stimulation device  100 . For example, an operational state or mode can include a properly secured transcranial electrical stimulation device  100 . An operation state or mode can include an increasing current of the transcranial electrical stimulation device  100 . An operation state or mode can include a decreasing current. An operation state or mode can include a transcranial electrical stimulation device  100  that has been removed from the head of the user by accident. An operation state or mode can include the termination of the stimulation session. An operation state or mode can include ending the stimulation session early. 
     The battery  714  can power the transcranial electrical stimulation device  100  during the stimulation sessions. For example, the battery  714  can be charged by connecting a charging cable to the charging port  408 . The battery  714  can take four hours to fully charge. The battery can provide for more than 30 stimulation sessions when fully charged. The battery  714  can be incapable of being changed when the transcranial electrical stimulation device  100  is in a powered state. The battery  714  can include an external power supply. The battery  714  can include a lithium-ion battery. The battery can operate at 3.7V and 250 mAh. 
     The transcranial electrical stimulation device  100  can include a sensor to detect orientation of the transcranial electrical stimulation device  100 . For example, the transcranial electrical stimulation device  100  can include an accelerometer. The transcranial electrical stimulation device  100  can include a tilt sensor to measure the tilt of the transcranial electrical stimulation device  100  with reference to gravity. The transcranial electrical stimulation device  100  can change the direction of the flow of current based on the orientation of the transcranial electrical stimulation device  100 . The direction of the flow of current can be controlled by user input. 
     Referring to  FIG. 8 , an exploded view of an embodiment of a transcranial electrical stimulation device  100 . The transcranial electrical stimulation device  100  can include a first non-conductive cup  812  (e.g., non-conductive portion of first conductive cup  112 ) and a second non-conductive cup  822  (e.g., non-conductive portion of second conductive cup  122 ). The first non-conductive cup  812  can be composed of an insulator (e.g., silicone, rubber). The first conductive cup  112  can nestle into the first non-conductive cup  812 . The first conductive cup  112  can be joined to the first non-conductive cup  812  by molding, an adhesive (e.g., gluing), or via operation of a pin lock  614 . The first conductive cup  112  can have a diameter of 5.3 cm. The first non-conductive cup  812  can have a diameter of 5.3 cm. The second non-conductive cup  822  can be composed of an insulator (e.g., silicone, rubber). The second conductive cup  122  can nestle into the second non-conductive cup  822 . The second conductive cup  122  can be joined to the second non-conductive cup  822  by molding, an adhesive (e.g., gluing), or via operation of a pin lock  614 . The second conductive cup  122  can have a diameter of 5.3 cm. The second non-conductive cup  822  can have a diameter of 5.3 cm. The transcranial electrical stimulation device  100  can include a back-side cover  830 . The back-side cover  830  can include a pin receiver  832 . The pin receiver  832  can receive a pin lock  614 . The pin receiver  832  can have a notch to lock the electrode  600  to the back-side cover  830 . 
     Referring to  FIG. 9 , a block diagram representation of one embodiment of a sponge  900  is shown. A sponge height  902  defined by the sponge  900  can be greater than a thickness defined by the first raised edge  410 . The sponge height  902  can be greater than a thickness defined by the second raised edge  412 . A sponge width  904  defined by the sponge  900  can be less than the first diameter  202 . The sponge width  904  can be less than the second diameter  212 . The sponge  902  can fit securely into the first conductive cup  112 . The sponge  902  can fit securely into the second conductive cup  122 . The sponge  900  can be pre-soaked in a saline solution before operation of the transcranial electrical stimulation device  100 . The sponge  900  can include various shapes (e.g., rectangular prism, cube, elliptic cylinder, among others). The sponge  900  can expand when soaked in saline solution. 
     Referring to  FIG. 10 , a block diagram representation of one embodiment of device components is shown. The transcranial electrical stimulation device  100  can include a control circuit  1002 , a power supply  1004 , electrodes  1006 , a LED  404 , a power button  1010  and an audio component  712 . The power supply  1004  can include the battery  714  described in a previous section of the disclosure. Electrodes  1006  can include the first electrode  110  and the second electrode  112 . The LED  1008  can include the LED  404  described in a previous section of the disclosure. The power button  1010  can include the power button  402  described in a previous section of the disclosure. The audio component  1012  can include the audio component  712  described in a previous section of the disclosure. 
     Referring to  FIG. 11 , a flow diagram of an example method  1100  for engaging in transcranial electrical stimulation is shown. The method  1100  can include securing a transcranial electrical stimulation device to a head of a user (BLOCK  1102 ). The method  1100  can include confirming that the transcranial electrical stimulation device is properly secured (BLOCK  1103 ). The method  1100  can include initiating, by a control circuit  1102 , a stimulation session (BLOCK  1104 ). The method  1100  can include increasing, by the control circuit  1102 , a current to a first current level over a first period of time (BLOCK  1106 ). The method  1100  can include maintaining, by the control circuit  1102 , the current at the first current level over a second period of time (BLOCK  1108 ). The method  1100  can include decreasing, by the control circuit  1102 , responsive to a termination condition, the current to second current level over a third period of time (BLOCK  1110 ). The method  1100  can include terminating, by the control circuit  1102 , the stimulation session (BLOCK  1112 ). 
     As set forth above, the method  1100  can include securing a transcranial electrical stimulation device to a head of a user (BLOCK  1102 ). Securing the transcranial electrical stimulation device  100  to the head of the user can include placing the first electrode  110  (or components coupled to the first electrode) and the second electrode  120  (or components coupled to the first electrode) flush against the forehead of the user. Also referring to  FIG. 3 , the strap  302  can wrap around the head of the user to secure the transcranial electrical stimulation device  100  to the head of the user. Securing the transcranial electrical stimulation device  100  to the head of the user can include adjusting the strap  302  to fit around users with different head sizes. The first electrode  110  can flex about the first post  114  so as to contour to the forehead of the user. Securing the transcranial electrical stimulation device  100  to the head of the user can include flexing the first electrode  110  about the first post  114 . The second electrode  120  can flex about the second post  124  so as to contour to the forehead of the user. Securing the transcranial electrical stimulation device  100  to the head of the user can include flexing the second electrode  120  about the second post  124 . Securing the transcranial electrical stimulation device  100  to the head of the user can include adjusting a first position of the first electrode  110  of the transcranial electrical stimulation device  100  and a second position of the second electrode  120  of the transcranial electrical stimulation device  100 . The transcranial electrical stimulation device  100  can target various areas of the brain of the user (e.g., dorsolateral prefrontal cortex or the motor cortex). The first electrode can be in contact with a first region of the forehead of the user and the second electrode can be in contact with a second region of the forehead. 
     The method  1100  can include confirming that the transcranial electrical stimulation device is properly secured (BLOCK  1103 ). Confirming that the transcranial electrical stimulation device  100  is properly secured can include confirming that the transcranial electrical stimulation device  100  is properly secured to the head of the user. If the transcranial electrical stimulation device  100  is properly secured to the head of the user, the control circuit  1102  can initiate a stimulation session. If the transcranial electrical stimulation device  100  is improperly secured to the head of the user, the control circuit  1102  can terminate the stimulation session. 
     The method  1100  can include initiating, by a control circuit, a stimulation session (BLOCK  1104 ). Initiating, by a control circuit  1102 , a stimulation session can include the control circuit  1102  coupling a power supply  1104  to a first electrode and a second electrode to enter a powered state. Initiating, by a control circuit  1102 , a stimulation session can include the transcranial electrical stimulation device  100  entering a powered state. Also referring to  FIG. 4 , a user can press and hold the power button  402  to turn on the transcranial electrical stimulation device  100 . The LED  404  can emit a blue light. The LED can flash periodically. The method  1100  can include confirming, by the LED through visual cues, that the transcranial electrical stimulation device  100  is properly secured to the head of the user. Initiating the stimulation session  1104  can occur responsive to a confirmation that the transcranial electrical stimulation device  100  is properly secured. Initiating a stimulation session can include initiating, by activating the power button  402 , the stimulation session. The LED can signal an operational state of the transcranial electrical stimulation device  100 . For example, an operational state can include proper placement of the transcranial electrical stimulation device  100 , a stimulation session, or a current increase or a current decrease. 
     The method  1100  can include increasing, by the control circuit, a current to a first current level over a first period of time (BLOCK  1106 ). Increasing a current to a first level over a first period of time can include flowing current through the head of the user from a first electrode  110  of the transcranial electrical stimulation device  100  to a second electrode  120  of the transcranial electrical stimulation device  100 . The first period of time can be between 10 seconds and 50 seconds, such as between 10 seconds and 15 seconds. The first period of time can be 30 seconds. The current can increase from 0 mA to a first current level (e.g., 1.2 mA). 
     The method  1100  can include maintaining, by the control circuit, the current at the first current level over a second period of time (BLOCK  1108 ). Maintaining the current at the first current level over a second period of time can include flowing current through the head of the user from a first electrode  110  of the transcranial electrical stimulation device  100  to a second electrode  120  of the transcranial electrical stimulation device  100 . The second period of time can be 20 minutes. The first current level can be 1.2 mA. The first current level can be adjustable to achieve a higher current level. The first current level can be adjustable to achieve a lower current level. Maintaining the current level at the first current level can include maintaining the current at a constant current. 
     The method  1100  can include decreasing, by the control circuit, responsive to a termination condition, the current to second current level over a third period of time (BLOCK  1110 ). Decreasing the current to second current level over a third period of time can include flowing current through the head of the user from a first electrode  110  of the transcranial electrical stimulation device  100  to a second electrode  120  of the transcranial electrical stimulation device  100 . The third period of time can be 30 seconds. The second current level can be 0 mA. The third period of time can be between 10 seconds and 50 seconds, such as between 10 seconds and 15 seconds. The second period of time can be 30 seconds. The current can decrease from first current level (e.g., 1.2 mA) to a second current level (0 mA). The termination condition can be a variety of conditions. For example, the termination condition can be a predetermined length of time (e.g., 20 minutes). The termination condition can be an interrupted stimulation session. For example, a user may want to end the stimulation session early. The user can activate the power button to decrease the current to the second current level over the third period of time. The termination condition can be met if the transcranial electrical stimulation device  100  is accidentally moved or removed from the head of the user. 
     The termination condition can be a resistance exceeding a threshold. For example, the termination condition can be that the resistance of the circuit exceeds a threshold of 15 kΩ. If the resistance of the circuit exceeds 15 kΩ, the control circuit  1002  can initiate a decrease of current over the third period of time. If the resistance of the resistance of the circuit is infinite, the control circuit  1002  can immediately stop the flow of current through the head of the user from the first electrode  110  of the transcranial electrical stimulation device  100  to the second electrode  120  of the transcranial electrical stimulation device  100 . 
     The method  1100  can include terminating, by the control circuit, the stimulation session (BLOCK  1112 ). Terminating, by a control circuit  1002 , a stimulation session can include the control circuit  1002  decoupling a power supply  1004  to the first electrode and the second electrode to exit the powered state. Terminating the stimulation session can include the transcranial electrical stimulation device  100  exiting the powered state. Terminating the stimulation session can include stopping the flow of current through the head of the user from a first electrode  110  of the transcranial electrical stimulation device  100  to a second electrode  120  of the transcranial electrical stimulation device  100 . Terminating a stimulation session can include terminating, by activating the power button  402 , the stimulation session. 
     In some embodiments, a method for engaging in transcranial electrical stimulation comprising securing a transcranial electrical stimulation device to a head of a user in a first orientation (as shown in  FIG. 2H ) such that a first electrode is electrically coupled and positioned proximate to a first surface region of the head and a second electrode is electrically coupled and positioned proximate to a second surface region of the head. The method includes initiating, via a control circuit, a stimulation session. The control circuit couples a power supply to the first electrode and the second electrode to enter a first powered state, increases a current to a first current level over a first period of time, wherein the current flows from the first electrode through the head of the user in a first direction to the second electrode (for instance, from the first surface region of the head to the second surface region of the head), maintains the current at the first current level over a second period of time, decreases, responsive to a termination condition, the current to a second current level over a third period of time, and terminates the stimulation session wherein the control circuit decouples the power supply to the first electrode and the second electrode to exit the powered state. The method also includes removing the transcranial electrical stimulation device from the head of the user. The method further includes securing the transcranial electrical stimulation device to the head of the user in a second orientation (as shown in  FIG. 2I ) such that the first electrode is electrically coupled and positioned proximate to the second surface region of the head and the second electrode is electrically coupled and positioned proximate to the first surface region of the head and initiating, via the control circuit, a second stimulation session. The control circuit couples the power supply to the first electrode and the second electrode to enter a second powered state; increases the current to the first current level over a third period of time, wherein the current flows from the first electrode through the head of the user in a second direction to the second electrode for instance, from the second surface region of the head to the first surface region of the head), maintains the current at the first current level over a fourth period of time, and decreases, responsive to a termination condition, the current to the second current level over a fifth period of time; and terminates the stimulation session, wherein the control circuit decouples the power supply to the first electrode and the second electrode to exit the powered state. The method further includes removing the transcranial electrical stimulation device from the head of the user. The first surface region of the head can be the left prefrontal cortex and the second surface region of the head can be the right prefrontal cortex or vice versa. 
     As utilized herein, the terms “approximately,” “about,” “substantially”, and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the disclosure as recited in the appended claims. 
     It should be noted that the term “exemplary” and variations thereof, as used herein to describe various embodiments, are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (and such terms are not intended to connote that such embodiments are necessarily extraordinary or superlative examples). 
     The term “coupled” and variations thereof, as used herein, means the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent or fixed) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members coupled directly to each other, with the two members coupled to each other using a separate intervening member and any additional intermediate members coupled with one another, or with the two members coupled to each other using an intervening member that is integrally formed as a single unitary body with one of the two members. If “coupled” or variations thereof are modified by an additional term (e.g., directly coupled), the generic definition of “coupled” provided above is modified by the plain language meaning of the additional term (e.g., “directly coupled” means the joining of two members without any separate intervening member), resulting in a narrower definition than the generic definition of “coupled” provided above. 
     The term “or,” as used herein, is used in its inclusive sense (and not in its exclusive sense) so that when used to connect a list of elements, the term “or” means one, some, or all of the elements in the list. Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is understood to convey that an element may be either X, Y, Z; X and Y; X and Z; Y and Z; or X, Y, and Z (i.e., any combination of X, Y, and Z). Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y, and at least one of Z to each be present, unless otherwise indicated. 
     References herein to the positions of elements (e.g., “top,” “bottom,” “above,” “below”) are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure.