S.H. Annabel Chen, PhD
The Clinical Brain Lab, Psychology, Nanyang Technological University, Singapore
The cerebellum has traditionally been regarded as a structure chiefly involved in motor control functions. However, this notion has been challenged when unexpected cognitive deficits were revealed by clinical and neuropsychological studies of patients with exclusive cerebellum damage. In addition, increasing functional neuroimaging studies revealed activations in the cerebellum, in which motor functions have been well controlled for. Recent meta-analyses of neuroimaging studies, as well as intrinsic connectivity studies have provided further support for the functional topography of the cerebellum in higher cognition. In this talk, I will describe a systematic investigation of the cerebellar contributions to verbal working memory, as an example. We conducted a series of neuroimaging studies to verify a cerebro-cerebellar neurocircuitry model of verbal working memory (WVM) set within a general theory of error-driven adjustment. In addition, an fMRI-guided Transcranial Magnetic Stimulation (TMS) study was conducted to verify the necessity of an identified cerebellar region for verbal working memory. This VWM paradigm was also applied to chronic alcoholics and similar cerebellar abnormalities were shown. These series of studies confirm the involvement of the cerebellum in verbal working memory. One of the research objectives is to extend this cerebro-cerebellar model to help elucidate cognitive deficits in disorders that involve the cerebellum, such as the dysconnectivity syndrome proposed for schizophrenia.