Mixedhandedness

Mixed-handedness, also called cross-dominance, refers to a pattern in which an individual does not consistently prefer the same hand for different activities. People may write with one hand but throw or use tools with the other, or switch hands between tasks. This contrasts with ambidexterity, where a person is equally skilled with both hands across tasks, and with consistent left- or right-handedness.

Prevalence estimates vary; mixed-handedness is relatively common among the general population, typically cited as roughly 10–20%.

Causes and development: Handedness emerges from genetic, developmental, and environmental factors that influence brain lateralization. Mixed-handedness is associated with less lateralized brain activity in some studies, but findings are heterogeneous and no single cause is established.

Assessment: Researchers commonly use standardized inventories, such as the Edinburgh Handedness Inventory, and observe performance across tasks (writing, throwing, tool use) to identify cross-task patterns.

Cognition and behavior: Some studies report differences in interhemispheric connectivity or bilateral processing, but results are inconsistent. Mixed-handedness has been explored in relation to neurodevelopmental conditions (e.g., dyslexia, ADHD), but evidence is inconclusive and causation is not established.

Clinical relevance and societal context: It is not a disorder. Most mixed-handed individuals function normally; attitudes toward handedness vary culturally and may influence how often mixed patterns are observed.