The pathophysiology of autism is the study of the physiological processes that cause or are otherwise associated with autism spectrum disorders.

In psychology, trait theory (also called dispositional theory) is an approach to the study of human personality. Trait theorists are primarily interested in the measurement of traits, which can be defined as habitual patterns of behavior, thought, and emotion.[1] According to this perspective, traits are aspects of personality that are relatively stable over time, differ across individuals (e.g. some people are outgoing whereas others are not), are relatively consistent over situations, and influence behaviour. Traits are in contrast to states, which are more transitory dispositions.

Autistic masking, also referred to as camouflaging or neurodivergent masking, is the conscious or subconscious suppression of autistic behaviors and compensation of difficulties in social interaction by autistic people with the goal of being perceived as neurotypical.[1][2] Masking is a learned coping strategy[3][4] that can be successful from the perspective of autistic people, but can also lead to adverse mental health outcomes.[1][5]

Self-stimulatory behavior, also known as "stimming" and self-stimulation, is the repetition of physical movements, sounds, words, moving objects, or other behaviors. Such behaviors are found to some degree in all people, especially those with developmental disabilities such as ADHD, as well as autistic people. People diagnosed with sensory processing disorder are also known to potentially exhibit stimming behaviors.

Snoezelen or controlled multisensory environment (MSE) is a therapy for people with autism and other developmental disabilities, dementia or brain injury. It consists of placing the person in a soothing and stimulating environment, called the "Snoezelen room", a form of sensory room. These rooms are specially designed to deliver stimuli to various senses, using lighting effects, color, sounds, music, scents, etc. The combination of different materials on a wall may be explored using tactile senses, and the floor may be adjusted to stimulate the sense of balance. The person is usually accompanied by an aide or therapist.

Frisson, also known as aesthetic chills or psychogenic shivers, is a psychophysiological response to rewarding stimuli that often induces a pleasurable or otherwise positively-valenced affective state and transient paresthesia, sometimes along with piloerection and mydriasis .The sensation commonly occurs as a mildly to moderately pleasurable emotional response to music with skin tingling; piloerection and pupil dilation not necessarily occurring in all cases.

An autonomous sensory meridian response (ASMR) is a tingling sensation that usually begins on the scalp and moves down the back of the neck and upper spine. A pleasant form of paresthesia, it has been compared with auditory-tactile synesthesia and may overlap with frisson. ASMR is a subjective experience of "low-grade euphoria" characterized by "a combination of positive feelings and a distinct static-like tingling sensation on the skin". It is most commonly triggered by specific auditory or visual stimuli, and less commonly by intentional attention control.

Autism, formally called autism spectrum disorder (ASD) or autism spectrum condition (ASC), is a neurodevelopmental disorder marked by deficits in reciprocal social communication and the presence of restricted and repetitive patterns of behavior. Other common signs include difficulties with social interaction, verbal and nonverbal communication, along with perseverative interests, stereotypic body movements, rigid routines, and hyper- or hyporeactivity to sensory input. Autism is clinically regarded as a spectrum disorder, meaning that it can manifest very differently in each person. For example, some are nonspeaking, while others have proficient spoken language. Because of this, there is wide variation in the support needs of people across the autism spectrum.

Excoriation disorder, more commonly known as dermatillomania, is a mental disorder on the obsessive–compulsive spectrum that is characterized by the repeated urge or impulse to pick at one's own skin, to the extent that either psychological or physical damage is caused.