Previous research has suggested that a probabilistic category learning task (e.g. weather prediction task) can be used to elucidate brain substrates of learning. We tested amnesic subjects with bilateral hippocampal damage due to hypoxia and matched controls on the weather prediction task and a variant, the "ice cream" task, which maintains a similar category structure. The hypoxic subjects wer...

In this study, we examined the role of the hippocampus in relational memory by comparing item recognition performance in amnesic patients with medial temporal lobe (MTL) damage and their matched controls. Specifically, we investigated the contribution of associative memory to item recognition using a cued recognition paradigm. Control subjects studied cue-target pairs once, whereas amnesic pati...

Nootropic activity of leaves of Prunella vulgaris was studied in mice. Elevated plus maze and passive avoidance paradigm were employed to evaluate learning and memory parameters. Scopolamine (0.4 mg/kg, i.p.) was used to induce amnesia in mice. The ethanolic extracts of leaves of Prunella vulgaris PV (50 and 100 mg/kg, p.o.) significantly attenuated amnesic deficits induced by scopolamine (0.4 ...

This study evaluated cholineresterase inhibitory activity of Korean white ginseng extract (WGE), red ginseng extract (RGE), and black ginseng extract (BGE) and the cholinergic effect on scopolamine (SCOP)-induced amnesic mice. WGE, RGE, and BGE inhibited acetylcholineserase (AChE), as well as butyrylcholineserase (BuChE) in a concentration-dependent manner. BGE presented strong inhibition of AC...

Is directionality of electroencephalographic (EEG) synchronization abnormal in amnesic mild cognitive impairment (MCI) and Alzheimer's disease (AD)? And, do cerebrovascular and AD lesions represent additive factors in the development of MCI as a putative preclinical stage of AD? Here we reported two studies that tested these hypotheses. EEG data were recorded in normal elderly (Nold), amnesic M...

Recent research has led some investigators to hypothesize that posthypnotic amnesia is characterized by a disruption in the memory search process and, more generally, by disorganization in memory retrieval. Data to test these hypotheses were provided by 141 male and female undergraduates administered the Stanford Hypnotic Susceptibility Scales, Forms B and C. Amnesia was assessed by the usual r...