Affiliations: Department of Radiology and Stanford University School
of Medicine, Stanford, CA, USA | Neurosciences Program, Stanford University School of
Medicine, Stanford, CA, USA | Department and Graduate Institute of Psychology,
National Taiwan University, Taipei, Taiwan | Division of Psychology, Nanyang Technological
University, Singapore | Department of Neurology, Johns Hopkins University,
Baltimore, MD, USA
Note: [] Corresponding author: John E. Desmond, Department of Neurology,
Division of Cognitive Neuroscience, The Johns Hopkins Hospital, Reed Hall
East – 2, 1620 McElderry Street, Baltimore, MD 21205, USA. Tel.: +1 410 614
3040; Fax: +1 410 502 2189; E-mail: [email protected]
Abstract: Verbal working memory (VWM) engages frontal and temporal/parietal
circuits subserving the phonological loop, as well as, superior and inferior
cerebellar regions which have projections from these neocortical areas.
Different cerebro-cerebellar circuits may be engaged for integrating aurally-
and visually-presented information for VWM. The present fMRI study investigated
load (2, 4, or 6 letters) and modality (auditory and visual) dependent
cerebro-cerebellar VWM activation using a Sternberg task. FMRI revealed
modality-independent activations in left frontal (BA 6/9/44), insular,
cingulate (BA 32), and bilateral inferior parietal/supramarginal (BA 40)
regions, as well as in bilateral superior (HVI) and right inferior (HVIII)
cerebellar regions. Visual presentation evoked prominent activations in right
superior (HVI/CrusI) cerebellum, bilateral occipital (BA19) and left parietal
(BA7/40) cortex while auditory presentation showed robust activations
predominately in bilateral temporal regions (BA21/22). In the cerebellum, we
noted a visual to auditory emphasis of function progressing from superior to
inferior and from lateral to medial regions. These results extend our previous
findings of fMRI activation in cerebro-cerebellar networks during VWM, and
demonstrate both modality dependent commonalities and differences in
activations with increasing memory load.
Keywords: fMRI, cerebellum, modality, verbal working memory, neuroimaging
