The circuitry of abulia: insights from functional connectivity MRI.
BACKGROUND
Functional imaging and lesion studies have associated willed behavior with the anterior cingulate cortex (ACC). Abulia is a syndrome characterized by apathy and deficiency of motivated behavior. Abulia is most frequently associated with ACC damage, but also occurs following damage to subcortical nuclei (striatum, globus pallidus, thalamic nuclei). We present resting state functional connectivity MRI (fcMRI) data from an individual who suffered a stroke leading to abulia. We hypothesized that, although structural imaging revealed no damage to the patient's ACC, fcMRI would uncover aberrant function in this region and in the relevant cortical networks.


METHODS
Resting state correlations in the patient's gray matter were compared to those of age-matched controls. Using a novel method to identify abnormal patterns of functional connectivity in single subjects, we identified areas and networks with aberrant connectivity.


RESULTS
Networks associated with memory (default mode network) and executive function (cingulo-opercular network) were abnormal. The patient's anterior cingulate was among the areas showing aberrant functional connectivity. In a rescan 3 years later, deficits remained stable and fcMRI findings were replicated.


CONCLUSIONS
These findings suggest that the aberrant functional connectivity mapping approach described may be useful for linking stroke symptoms to disrupted network connectivity.
Department of Neurology, Washington University School of Medicine at Washington University, St. Louis, MO, USA.
J S
JS
Siegel
Department of Neurology, Washington University School of Medicine at Washington University, St. Louis, MO, USA ; Mallinckrodt Institute of Radiology, Washington University School of Medicine, Washington University, St. Louis, MO, USA.
A Z
AZ
Snyder
Department of Neurology, Washington University School of Medicine at Washington University, St. Louis, MO, USA.
N V
NV
Metcalf
Department of Neurology, Washington University School of Medicine at Washington University, St. Louis, MO, USA.
R P
RP
Fucetola
Department of Neurology, Washington University School of Medicine at Washington University, St. Louis, MO, USA.
C D
CD
Hacker
Mallinckrodt Institute of Radiology, Washington University School of Medicine, Washington University, St. Louis, MO, USA.
J S
JS
Shimony
Department of Neurology, Washington University School of Medicine at Washington University, St. Louis, MO, USA.
G L
GL
Shulman
Department of Neurology, Washington University School of Medicine at Washington University, St. Louis, MO, USA ; Mallinckrodt Institute of Radiology, Washington University School of Medicine, Washington University, St. Louis, MO, USA ; Department of Anatomy & Neurobiology, Washington University School of Medicine, Washington University, St. Louis, MO, USA.
M
M
Corbetta
D000328:Adult; D020324:Amnesia, Anterograde / Q000150:complications / Q000503:physiopathology; D001931:Brain Mapping; D006179:Gyrus Cinguli / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009042:Motivation / Q000502:physiology*; D009415:Nerve Net / Q000503:physiopathology; D012146:Rest; D020521:Stroke / Q000150:complications / Q000503:physiopathology; D013702:Temporal Lobe / Q000503:physiopathology*
Abulia; Anterior cingulate; Executive function; Functional connectivity; apathy; fMRI