Early Disrupted Neurovascular Coupling and Changed Event Level Hemodynamic Response Function in Type 2 Diabetes: An fMRI Study

Event-related fMRI and the hemodynamic response.

Event-related functional magnetic resonance imaging (ER-fMRI) methods are allowing a new spectrum of task designs to be explored with brain imaging techniques. Individual trial events can be presented rapidly, in randomly intermixed order, and the hemodynamic responses associated with individual trial events appreciated. The basis of ER-fMRI is that the hemodynamic response tracks neuronal acti...

Stimulus repetition and hemodynamic response refractoriness in event-related fMRI.

We investigated the extent of hemodynamic recovery following the paired presentation of either identical or different faces at two different inter-stimulus intervals (ISI). Signal recovery was consistently better at an ISI of 6 sec compared to 3 sec. Significantly less signal recovery was associated with identical faces compared to different faces in bilateral mid-fusiform and right prefrontal ...

Regional differences in the refractory period of the hemodynamic response: an event-related fMRI study.

We investigated the characteristics of the hemodynamic response (HDR) to paired presentations of visual face stimuli using functional magnetic resonance imaging (fMRI). Photographs of faces were presented singly or in pairs with either a 1-s or 6-s intrapair interval (IPI). Each trial (single face or face pairs) was followed by an intertrial interval of 16-20 s. Faces were presented at fixation...

Dermal neurovascular dysfunction in type 2 diabetes.

OBJECTIVE To review evidence for a relationship between dermal neurovascular dysfunction and other components of the metabolic syndrome of type 2 diabetes. RESEARCH DESIGN AND METHODS We review and present data supporting concepts relating dermal neurovascular function to prediabetes and the metabolic syndrome. Skin blood flow can be easily measured by laser Doppler techniques. RESULTS Heat...

Robust estimation of the hemodynamic response function in asynchronous multitasks multisessions event-related fMRI paradigms