Domain Specific Lateralization of the Frontal Processes Informing Inhibition: A TMS Study
Response inhibition is the suppression of actions that are inappropriate given some wider context or goal, a capacity that is vital for everyday functioning. In this thesis the theoretical backdrop of executive functioning is discussed, before exploring current research into response inhibition and its neural underpinnings. A theory by Mostofsky and Simmonds (2008) holds that when the decision to inhibit a behavior is a complex one, task dependent parts of an inhibitory network in the prefrontal cortex are utilized. The current thesis argues on the basis of observed biases in the literature, for the possibility that this task dependent engagement features domain specific lateralization. In order to investigate this, a transcranial magnetic stimulation [TMS] experiment is then presented where four go/no-go tasks, spread across language and spatial domains in complex and simple forms, are performed following TMS. Stimulation sites include the right posterior inferior frontal gyrus, the left posterior inferior frontal gyrus, and sham stimulation. Results are then discussed, however implications are limited, likely due to low statistical power.