Severe Apathy Due to Injury of Prefronto-caudate Tract

Clinical and radiological correlates of apathy in multiple sclerosis

BACKGROUND

Although apathy has been associated with fronto-striatal dysfunction in several neurological disorders, its clinical and magnetic resonance imaging (MRI) correlates have been poorly investigated in people with multiple sclerosis (PwMS).

OBJECTIVES

To evaluate clinical variables and investigate microstructural integrity of fronto-striatal grey matter (GM) and white matter (WM) structures using diffusion tensor imaging (DTI).

METHODS

A total of 123 PwMS (age: 40.25 ± 11.5; female: 60.9%; relapsing-remitting multiple sclerosis: 75.6%) were prospectively enrolled and underwent neurological and neuropsychological evaluation, including Expanded Disability Status Scale (EDSS), Apathy Evaluation Scale (AES-S), Hospital Anxiety and Depression Scale (HADS), Modified Fatigue Impact Scale (MFIS) and brain 3T-MRI volumes of whole brain, frontal/prefrontal cortex (PFC) and subcortical regions were calculated. DTI-derived metrics were evaluated in the same GM regions and in connecting WM tracts.

RESULTS

Apathetic PwMS (32.5%) showed lower education levels, higher HADS, MFIS scores and WM lesions volume than nonapathetic PwMS. Significant differences in DTI metrics were found in middle frontal, anterior cingulate and superior frontal PFC subregions and in caudate nuclei. Significant alterations were found in the right cingulum and left striatal-frontorbital tracts.

CONCLUSIONS

Apathy in PwMS is associated with higher levels of physical disability, depression, anxiety and fatigue together with lower educational backgrounds. Microstructural damage within frontal cortex, caudate and fronto-striatal WM bundles is a significant pathological substrate of apathy in multiple sclerosis (MS).

Cerebral cortex Functional Networks of Transdermal Electrical Stimulation at Daling (PC7) Acupoint

The cerebral cortex functional network of Electroencephalogram (EEG) signals during transcutaneous electrical acupoint stimulation (TEAS) on 21 healthy subjects was constructed by using three modules: standard low-resolution brain electromagnetic tomography (sLORETA), phase-locking value (PLV), and complex network. We investigated the brain functional network triggered by PC7 stimulation by comparing with resting state and non-acupoint stimulation. The results showed that the PC7 stimulation mainly activated frontal lobe and temporal lobe including prefrontal cortex (BA10), insular lobe (BA13), temporal gyrus (BA22), anterior cingulate cortex (BA32), temporal pole (BA38), dorsolateral prefrontal cortex (BA46), and inferior frontal cortex (BA47), which are all closely linked to cognition, spirit, and emotion in brain. Furthermore, the degrees of node in frontal, temporal, and whole brain are increased significantly or extreme significantly with p < 0.05, p < 0.05, and p < 0.01, respectively; clustering coefficient in frontal, temporal, and whole brain are all statistically significant (p < 0.05). The information transmission efficiency of cerebral cortex has been greatly improved. During PC7 stimulation, the topological changes in the activation of cerebral regions and cortical functional networks are consistent with the therapeutic effect, which may provide theoretical support for acupoint stimulation to regulate nerve function.