Short-term memory deficits correlate with hippocampal-thalamic functional connectivity alterations following acute sleep restriction.

Acute sleep restriction heavily influences cognitive function, affecting executive processes such as attention, response inhibition, and memory. Previous neuroimaging studies have suggested a link between hippocampal activity and short-term memory function. However, the specific contribution of the hippocampus to the decline of short-term memory following sleep restriction has yet to be established.

Rapid eye movement sleep behavior disorder in patients with probable Alzheimer's disease.

Background And Aims: Rapid eye movement (REM) sleep behavior disorder (RBD) is commonly associated with neurodegenerative disorders characterized by α-synuclein deposition, including Parkinson's disease, multiple system atrophy, and Lewy body dementia. However, this tendency in tauopathy-mediated diseases is rare and only sporadically reported. We systematically illustrate the occurrence of RBD and sleep features among a cohort of patients with Alzheimer's disease (AD), a non-synucleinopathy.

A functional MRI evaluation of frontal dysfunction in patients with severe obstructive sleep apnea.

Background: This study focused on frontal dysfunction during a brief visual delayed matching-to-sample (DMS) task in patients with severe obstructive sleep apnea syndrome (OSAS). We also aimed to assess whether mismatch- or match-task would be more sensitive in the evaluation of OSAS frontal impairment and to determine the factors responsible for the association of the task performance and frontal activation.

Methods: Nine severe OSAS patients and 9 age-matched healthy subjects were studied with an event-related functional magnetic resonance imaging (fMRI).

A mismatch process in brief delayed matching-to-sample task: an fMRI study.

Our previous ERP studies have consistently demonstrated that a negativity N270 elicited by incongruent information in visual S1-S2 matching task represents a type of conflict process, which is distinct from that represented by the classic conflict task or other negative components in delayed matching-to-sample stimulus presentation patterns, since the inter-stimulus interval between S1 and S2 was presented as shorter as 500 ms. The N270 component of ERP was shown to reflect conflict processing during the simple working memory operations. In the present study, a functional MRI (fMRI) was used to investigate the visuospatial characteristics of brain activation associated with the task eliciting N270.

REM sleep behavior disorder in a patient with pontine stroke.

Rapid eye movement (REM) sleep behavior disorder (RBD) is frequently seen in patients with neurodegenerative diseases. It can also be seen in brainstem lesions involving the pons. However, RBD in patients with a pure pontine infarction has been rarely reported.

Distinctive conflict processes associated with different stimulus presentation patterns: an event-related potential study.

Twelve subjects were asked to perform visual stimulus presentation tasks. Two figures were presented either simultaneously or sequentially. They were either in congruity (same shapes) or in conflict (different shapes) with each other.