Can an observational method of assessing hand preference be used to predict language lateralisation?

Area of Science:

• Neuroscience
• Cognitive Psychology
• Psycholinguistics

Background:

• Hand preference is a key indicator of brain lateralisation.
• Understanding the relationship between handedness and language processing is crucial for cognitive neuroscience.
• Existing questionnaires for assessing hand preference vary in their methodology and validity.

Purpose of the Study:

• To evaluate the WatHand Cabinet Test (WHCT) as an accurate measure of hand preference compared to the Waterloo Handedness Questionnaire (WHQ).
• To determine if WHCT and WHQ yield similar classifications of individuals into language lateralisation groups.
• To investigate the association between the direction and degree of hand preference and language lateralisation.

Main Methods:

• 142 participants (82 right-handers, 60 left-handers) completed both the WHQ and WHCT.
• Participants underwent a fused-words dichotic listening test to assess language lateralisation.
• Correlation analyses were performed between WHCT, WHQ, and dichotic listening results.

Main Results:

• A high correlation was found between the WHCT and WHQ, indicating their comparability in measuring hand preference.
• Both WHCT and WHQ effectively classified participants into similar language lateralisation groups.
• A predictable pattern of language lateralisation was observed across different handedness groups, regardless of the assessment method used.

Conclusions:

• The WatHand Cabinet Test (WHCT) is a reliable and robust alternative to the Waterloo Handedness Questionnaire (WHQ) for assessing hand preference.
• Hand preference, as measured by both subjective questionnaires and objective measures, consistently relates to language lateralisation patterns.
• These findings support the use of the WHCT in research investigating the neurocognitive underpinnings of language lateralisation.