1. Department of Computer Science
Handedness and Brain Lateralization
in Language Processing
Zongyi Wang
How do you know what’s going on in your brain?
At the Cognition and Brain lab, we study language, memory and the brain using the ERP (event related potential) technique. ERPs, which are derived from electroencephalographic (EEG) recordings, are a direct measure of neocortical activity that tracks brain states continuously and instantaneously.
My PURE Project
Problem: Need to collect initial screening data on experimental subjects, paper forms require manual data entry
Solution: Design digital forms for handedness assessment and other screening (xml); use OpenDataKit Collect on Android Tablet
What is the relationship between handedness and hemispheric lateralization of language processing?
Strong linear trend (more left handed more right hemi dominance) [2]:
Strong right-handed -> left hemisphere dominant for language production (96%)
Strong left-handed -> left hemisphere dominant less often (only 73%)
With left-handed family members, dominance of left hemisphere reduced[1] (genetic factors)
Differences due to familial handedness apparent in ERP waveform (see below)
14 subjects reading a
series of isolated sentences
What have I learned?
Xml for questionnaire forms
OpenDataKit for data collection
EEG/ERP technique (cognitive neuroscience)
Relation between handedness and the brain
Future directions:
Streamlining forms, using with real participants!
Acknowledgements &
References
Cybelle Smith, mentor
Prof. Kara D. Fedemeier
P.U.R.E
[1] Kutas, M., Van Petten, C., & Besson, M. (1988). Event-related potential asymmetries during the reading of sentences. Electroencephalography and clinical Neurophysiology, 69(3),
[2] Knecht, S., Dräger, B., Deppe, M., Bobe, L., Lohmann, H., Flöel, A., ... & Henningsen, H. (2000). Handedness and hemispheric language dominance in healthy humans. Brain, 123(12),
[3] Herning, R. I., Better, W., & Cadet, J. L. (2008). EEG of chronic marijuana users during abstinence: relationship to years of marijuana use, cerebral blood flow and thyroid function. Clinical Neurophysiology, 119(2),
What other factors, besides handedness, affect EEG and ERP signals?
Females have thinner skulls -> larger EEG signals
Skull fracture may distort the EEG signal
Drug use can affect cognition, which also will affect aspects of the EEG signal (e.g. chronic marijuana users may show more frontal alpha activity[3])
Department of Computer Science
University of Illinois at Urbana-Champaign