What is the study for? The goal of this study is to characterize biophysical signals simultaneously co-registered from the person's nervous systems. To that end the investigators use multiple wearable biosensors (electroencephalogram, electrocardiogram, kinematics,etc.) and have the person move naturally during activities that are similar to what the person would do in activities of daily living. These include walking, walking with a metronome in the background and walking while breathing at the metronome's pace. The purpose of the study is to learn about the inherent properties of the biorhythms of each person in order to build a proper neurotypical scale and measure the departure of several groups of subjects from this typical ranges. These include Autism Spectrum Disorder(s), ADHD (Attention-deficit/hyperactivity disorder) , Asperger's Syndrome, Alzheimer's Disease, and/or Fragile X syndrome. This study does not provide any recommendations of diagnosis or treatment. It is merely a characterization of the person's biorhythms across these conditions.

What will the participant do? The participant will perform naturalistic behaviors (ex. walk naturally around the room, point at an object) while hearing a metronome beating in the background. At certain points, the participant will be instructed to breathe along with the beat of the metronome. During this experiment, the participant will be wearing a wireless Electroencephalographic (EEG) cap to record brain activity, wireless motion sensors around the body to record movement, and wireless electrocardiogram (ECG) on the chest to record heart activity.The participant will also be wearing Zeblok insoles placed inside their shoes, to monitor their gait. The recorded biophysical signals are to be used to assess biorhythms of the nervous system from an already diagnosed participants and neurotypical participants, as this experiment is designed to study and characterize the biophysical signals of various populations. The study does not provide criteria for diagnosis, nor does it provide recommendations for treatments. The study is merely characterizing the ranges of biophysical data and their variability across different populations to measure departure from neurotypical features. Please note, wearing a wireless EEG cap will involve applying electrode gel (similar to hair gel) on the participant's hair.

How long is the experiment? The experiment itself will take 45 minutes - comprising 3 walking trials lasting 15 minutes each - but this can be reduced depending on the participant's disposition. Breaks for light refreshments and sensory toys will be provided as needed. The setup will take an additional 15-30 minutes.

Where/when does the experiment take place? The experiment will be conducted at the Sensory-motor Integration Lab, Psychology Building on Busch campus, at Rutgers University (152 Frelinghuysen Road, Piscataway, NJ 08854). If necessary the experiment may also be conducted at the participant's home. Based on the availability of the participant and the experimenter, the date and place can be coordinated any day and time of the week - including weekends. Additional members of staff can provide on-site childcare for siblings upon request.