stereotypies

Stereotypies are repetitive, invariant patterns of behavior that appear purposeless or nonfunctional. They are observed in both humans and other animals and tend to persist over time, repeating the same movements or sounds with little variation.

In animals, stereotypies are common in captive or restricted environments and are considered a welfare indicator. Examples include crib-biting and tongue-clicking in horses, weaving or pacing in zoo and laboratory animals, and repetitive grooming or rocking in primates. Causes are multifactorial and often relate to environmental inadequacy, such as limited space, lack of variety, social isolation, or inconsistent routines. They may reflect an attempt to cope with stress, boredom, or unmet needs, and can become maladaptive if they interfere with health or social functioning.

In humans, stereotypies are repetitive, nonfunctional actions often associated with neurodevelopmental disorders (most notably autism spectrum disorders and Rett syndrome), intellectual disability, or certain genetic conditions. They can appear in early childhood or during periods of increased fatigue or stress. Stereotypies in humans are differentiated from tics by their less suppressible, more rhythmic, and invariability in form, though overlaps exist.

Diagnosis typically involves behavioral observation and consideration of medical, neurological, and welfare factors. Management focuses on reducing distress and improving environmental conditions or care routines. In animals, enrichment, social housing, regular feeding schedules, and addressing pain or discomfort can lessen stereotypies. In humans, interventions may include therapy, education, and addressing underlying conditions; pharmacological options are limited and targeted to associated symptoms.

Research continues into the neurobiological mechanisms of stereotypies, including neural circuits related to habit formation and reward processing.