Abnormal Functional Frontal Asymmetry and Behavioral Correlates in Adult ADHD: A TMS-EEG Study

Abnormal functional brain asymmetry and deficient response inhibition are two core symptoms of attention deficit hyperactivity disorder (ADHD). However, it is not known whether these symptoms are inter-related and whether they result from altered frontal excitability or compromised interhemispheric connectivity. We studied these issues in 52 ADHD and 43 non-clinical adults by comparing: (1) stop-signal reaction time (SSRT); (2) frontal asymmetry of the N200 event-related potential component, which is evoked during response inhibition and is lateralized to the right hemisphere; (3) TMS-evoked potential (TEP) in the right frontal hemisphere, which is indicative of local cortical excitability; and (4) frontal right-to-left interhemispheric TMS signal propagation (ISP), which is reversely indicative of interhemispheric connectivity.
Source: BRAIN STIMULATION: Basic, Translational, and Clinical Research in Neuromodulation - Category: Neurology Authors: Source Type: research