The Association Between Eye Movements and Cerebellar Activation in a Verbal Working Memory Task.
It has been argued that cerebellar activations during cognitive tasks may masquerade as cognition, while actually reflecting processes related to movement planning or motor learning. The present study investigated whether the cerebellar load effect for verbal working memory, that is, increased activations in lobule VI/Crus I and lobule VIIB/VIIIA, is related to eye movements and oculomotor processing. Fifteen participants performed an fMRI-based Sternberg verbal working memory task. Oculomotor and cognitive task demands were manipulated by using closely and widely spaced stimuli, and high and low cognitive load. Trial-based quantitative eye movement parameters were obtained from concurrent eye tracking. Conventional MRI analysis replicated the cerebellar load effect in lobules VI and VIIB/VIIIa. With quantitative eye movement parameters as regressors, analysis yielded very similar activation patterns. While load effect and eye regressor generally recruited spatially distinct neocortical and cerebellar regions, conjunction analysis showed that a small subset of prefrontal areas implicated in the load effect also responded to the eye regressor. The present results indicate that cognitive load-dependent activations in lateral superior and posteroinferior cerebellar regions in the Sternberg task are independent of eye movements occurring during stimulus encoding. This is inconsistent with the notion that cognitive load-dependent cerebellar activations merely reflect oculomotor processing.
Department of Neurology, Division of Cognitive Neuroscience, Division of Cognitive Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA Institute of Medical Psychology and Systems Neuroscience, University of Muenster, 48149 Münster, Germany.
Jutta
J
Peterburs
Department of Neurology, Division of Cognitive Neuroscience, Division of Cognitive Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Dominic T
DT
Cheng
Department of Neurology, Division of Cognitive Neuroscience, Division of Cognitive Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
John E
JE
Desmond
D000328:Adult; D002531:Cerebellum; D003071:Cognition / Q000502:physiology*; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009415:Nerve Net / Q000502:physiology; D013647:Task Performance and Analysis; D014706:Verbal Learning / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult
cerebellum; cognition; eye tracking; fMRI; working memory