Abstract:
A neural physiological method and apparatus for keeping the brain in wakefulness, in which the trigeminal nerves on the forehead are stimulated with a mild electrical current neuronal modulating signal of a range of frequencies and amplitudes in combination transmitted to the brain functional site locus coeruleus, resulting in inhabitation of the brain functional site thalamic reticular nucleus such that the thalamic reticular nucleus does not release inhibitory neurotransmitters for blocking the communication pathways between the thalamus and the cortical regions in the brain, keeping the brain in wakefulness.

Description:
RELATED APPLICATIONS 
       [0001]    The present invention corresponds to the U.S. Provisional Patent Application 61/856,108, which has the title: “Neural Physiological Apparatus for Wakefulness”. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is related to methods and apparatus for neural physiological modulating neuronal activation to keep the brain in wakefulness. 
       BACKGROUND OF THE INVENTION 
       [0003]    For operational safety and accuracy, there is a need to keep the brain in wakefulness, for which people usually drink coffee or smoke cigarettes to keep the brain awake, and some people stimulate their head or body with mechanical or electrical means. The present invention provides a method of neural physiological stimulation to modulate neuronal activations in the brain for keeping the brain in wakefulness, including modulating upwards the neuronal activation at the brain site, locus coeruleus, via trigeminal nerve stimulation, as well as a neural physiological method of sensing the drowsiness of the brain for automatic control of the neural physiological stimulation for keeping the brain in wakefulness. 
       FEATURES OF THE INVENTION 
       [0004]    The first feature of this invention is to keep the brain in wakefulness by modulating the neuronal activations of the brain drowsiness/wakefulness network including the locus coeruleus (LC), ventrolateral preoptic nucleus (VLPO), laterodorsal tegmental nucleus (LDT), pedunculopontine nucleus (PPT), thalamic reticular nucleus (TRN), via trigeminal nerve stimulation. 
         [0005]    The second feature of this invention is to sense the brain drowsiness for automatically controlling the modulation of the neuronal activations of the brain drowsiness/wakefulness network for wakefulness. 
         [0006]    The third feature of the present invention is to sense the brain drowsiness and to predict sleep-onset by detecting and measuring the burst of electric firing from the TRN in releasing inhibitory neurotransmitters that suppress/block communications between the thalamus and cortical regions and result in drowsiness and then further in sleep-onset. 
         [0007]    The forth feature of the present invention is to detect and measure the bursts of electric firing from the TRN in releasing inhibitory neurotransmitters by sensing and measuring the scalp EEG features, such as the EEG spindles resulted from the burst of electric firing of the TRN in inhibitory neurotransmitter releasing. 
         [0008]    The fifth feature of the present invention is to measure the level of drowsiness by quantifying the scalp EEG features, such as EEG spindles resulted from the burst of electric firing of the TRN in inhibitory neurotransmitter releasing, and measuring the quantities, such as the density, magnitude, and frequency of the spindles. 
         [0009]    The sixth feature of the present invention is to predict sleep-onset based on the quantities of the scalp EEG features resulted from the burst of electric firing of the TRN in inhibitory neurotransmitter releasing, such as the EEG spindles, including the density, magnitude, and frequency. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  shows the neurophysiologic formation mechanism of drowsiness, in which the bursts of TRN neuronal activation causes inhibitory neurotransmitter releasing in inhabitation of communication pathways between the thalamus and most cortical regions, resulting in drowsiness and then sleep-onset; and at the mean time electrically the bursts of TRN neuronal activation result in EEG spindles measureable throughout the brain and on the scalp and forehead. 
           [0011]      FIG. 2  shows a mild electric stimulation on the trigeminal nerve, transmitting neuronal modulating signals to the LC to modulate upwards the neuronal activation at the LC. 
           [0012]      FIG. 3  shows that having the neuronal activation modulated upwards, the LC passes inhibitory transmission to the VLPO, and the inhibited VLPO losing its inhabitation on the LDT and PPT, such that LDT and PPT increase in activation and pass inhibitory transmission to the TRN, re-establishing the excitatory transmission/communications between the thalamus and cortical regions. 
           [0013]      FIG. 4  shows one embodiment of the present invention, which is in a cap form with two electrodes mounted on it for contacting with the forehead, and with a battery powered circuit board mounted on it, providing one or more of the three functions: 1) the neural physiological stimulation for modulating the neuronal activation in the brain for keeping the brain in wakefulness, 2) sensing the brain drowsiness level and predicting sleep-onset based on EEG measurement, and 3) automatically turning on or off the neural physiological stimulation and automatically switching between the function modes. 
           [0014]      FIG. 5  shows another embodiment of the present invention, which is in a frame form with two electrodes mounted on it for contacting with the forehead, and with a battery powered circuit board on it, providing one or more of the three functions: 1) the neural physiological stimulation for modulating the neuronal activation in the brain for keeping the brain in wakefulness, 2) sensing the brain drowsiness level and predicting sleep-onset based on EEG measurement, and 3) automatically turning on or off the neural physiological stimulation and automatically switching between the function modes. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0015]    As shown in  FIG. 1 , when the brain  1  transits from its wakefulness mode into a mode of mental fatigue/drowsiness, the sleep promoting side VLPO  2  increases in its neuronal activation, releasing inhibitory neurotransmitters to inhibit the functional sites LDT  3 , PPT  4 , and LC  16 , and thus enabling the TRN  6  activation in bursts in releasing inhibitory neurotransmitters forming blockages  7  along the communication path ways  8  between the thalamus  9  and cortical regions  10 , resulting in drowsiness mode of the brain; at the mean time of the TRN  6  activating in bursts in releasing inhibitory neurotransmitters, the neuronal activation generates neuronal electric firing bursts in special waves of electric potential throughout the brain  1 , which can be measured on the scalp  11  and forehead  12  in EEG spindle waveform  13  (see  FIG. 1 ). 
         [0016]    As shown in  FIG. 2  and  FIG. 3 , in this invention, to keep the brain in wakefulness, the trigeminal nerves  14  on the forehead are stimulated with pulsed mild electrical current  15  of a range of frequencies and amplitudes in combination to transmit neuronal modulation signals to the brain functional site LC  16 , increasing the neuronal activation at LC  16 , enhancing the inhabitation pathway  17  of LC  16  to the VLPO  2 , such that the VLPO  2  is inhibited, resulting a blockage  18  along its pathway in releasing inhibitory neurotransmitters to inhibit the functional sites LDT  3 , PPT  4 , and LC  5 , and consequently the LDT  3  and PPT  4  inhibit the TRN  6  in releasing inhibitory neurotransmitters, getting the communication pathways  8  between the thalamus  9  and cortical regions  10  unblocked—keeping the brain  1  in wakefulness. 
         [0017]    Also in this invention, the triggering for turning on the trigeminal nerve stimulation to modulate up wards the LC  16  neuronal activation for keeping the brain  1  in wakefulness may be automatically controlled by detecting the EEG spindle  13  associated with brain drowsiness, through EEG measurement, such as scalp EEG measurement and signal processing, with electrodes  19  and signal processing and control circuit and battery powered board  20 , as shown in  FIG. 4 . Once the EEG spindle  13  is detected, by the signal processing and control circuit and battery powered board  20  the trigeminal nerve stimulation  15  will be triggered on and then the neuronal activation of LC  16  will be modulated upwards, inhibiting the TRN  6  until the EEG spindle  13  disappears—keeping the brain  1  in wakefulness. 
         [0018]    The method of the present invention may result in various embodiments of the present invention. One of the embodiments may be in a cap form, as shown in  FIG. 4 , in which a cap  21  for wearing on a head has two electrodes  19  on the interior front for contacting with the forehead  12  (see  FIG. 1 ), a signal processing and control circuit and battery powered board  20 , and a tightening band  22 . It may provide one or more of the three functions: 1) stimulating the trigeminal nerves  14  on the forehead  12  with pulsed mild electrical current  15  of a range of frequencies and intensities in combination generated from the signal processing and control circuit and battery powered board  20 , to transmit neuronal modulation signals to the brain functional site LC  16 , increasing the neuronal activation at LC  16 , enhancing the inhabitation pathway  17  of LC  16  to the VLPO  2 , such that the VLPO  2  is inhibited, resulting a blockage  18  along its pathway in releasing inhibitory neurotransmitters to inhibit the functional sites LDT  3 , PPT  4 , and LC  5 , and consequently the LDT  3  and PPT  4  inhibit the TRN  6  in releasing inhibitory neurotransmitters, getting the communication pathways  8  between the thalamus  9  and cortical regions  10  unblocked—keeping the brain  1  in wakefulness; 2) sensing the brain drowsiness level and predicting sleep-onset based on EEG measurement by taking EEG signals with the electrodes  19  from the forehead  12  and processing the EEG signals with the signal processing and control circuit and battery powered board  20 ; 3) automatically turning on or off the trigeminal nerve stimulation and automatically switch between the function modes between stimulation and sensing by the signal processing and control circuit and battery powered board  20 . 
         [0019]    Another one of the embodiments may be in a frame form, as shown in  FIG. 5 , in which a frame  23  for wearing on the forehead  12  (see  FIG. 1 ) and laying on the ears has two electrodes  24  on the interior front for contacting with the forehead  12 , a pair of signal processing and control circuit and battery powered boards  25 , and a tightening band  26 . It may provide one or more of the three functions: 1) stimulating the trigeminal nerves  14  on the forehead  12  with pulsed mild electrical current  15  of a range of frequencies and intensities in combination generated from the signal processing and control circuit and battery powered boards  25 , to transmit neuronal modulation signals to the brain functional site LC  16 , increasing the neuronal activation at LC  16 , enhancing the inhabitation pathway  17  of LC  16  to the VLPO  2 , such that the VLPO  2  is inhibited, resulting a blockage  18  along its pathway in releasing inhibitory neurotransmitters to inhibit the functional sites LDT  3 , PPT  4 , and LC  5 , and consequently the LDT  3  and PPT  4  inhibit the TRN  6  in releasing inhibitory neurotransmitters, getting the communication pathways  8  between the thalamus  9  and cortical regions  10  unblocked—keeping the brain  1  in wakefulness; 2) sensing the brain drowsiness level and predicting sleep-onset based on EEG measurement by taking EEG signals with the electrodes  24  from the forehead  12  and processing the EEG signals with the signal processing and control circuit and battery powered boards  25 ; 3) automatically turning on or off the trigeminal nerve stimulation and automatically switch between the function modes between stimulation and sensing by the signal processing and control circuit and battery powered boards  25 .