Dynamic information flow analysis in Vascular Dementia patients during the performance of a visual oddball task

• This is the first study of the dynamic information flow in Vascular Dementia (VaD).
• VaD patients showed a decline in the information flow during a visual oddball task.
• DTF analysis gives an explanation for cognitive functions’ deficits in VaD patients.

This study investigated the information flow in patients with Vascular Dementia (VaD). Twelve VaD patients and twelve age-matched controls participated in the study. EEG signal was recorded when subjects were performing a visual oddball task. Information flow was analyzed between 9 electrodes in frontal, central, and parietal lobes using short-window Directed Transfer Function (sDTF). VaD patients presented a significant decline in the information flow from parietal to frontal and central lobes, compared with the healthy elderly. This decline mainly occurred in delta, theta, and lower alpha bands, from about 200 ms to 300 ms after target stimulus onset. The findings indicated an impaired parietal-to-frontal and parietal-to-central connectivity in VaD patients, which may be one reason for the cognitive deficits in VaD patients.