The hippocampus is critical for spatial learning and memory. Hippocampal neurons in awake animals exhibit place field activity that encodes current location, as well as sharp-wave ripple (SWR) activity during which representations based on past experiences are often replayed. The relationship between these patterns of activity and the memory functions of the hippocampus is poorly understood. We...

It has been proposed that reversal learning is impaired following damage to the orbitofrontal and ventromedial frontal cortex (OFC/VMFC) and to the medial temporal lobe (MTL), including the hippocampal formation. However, the exact characteristics of the MTL-associated reversal learning deficit are not known. To investigate this issue, we assessed 30 newly diagnosed patients with amnestic mild ...

The purpose of this study was to investigate the neurofunctional substrate of verbal learning and memory impairments in schizophrenic patients. In this pilot study, our aim was to compare the memory disturbance of schizophrenic patients to the subcortico-frontal memory profile of Parkinson's disease (PD) patients. The California Verbal Learning Test, a verbal episodic memory test, was administe...

The present study examined word learning difficulties in Chinese dyslexic children, readers of a nonalphabetic script. A total of 105 Hong Kong Chinese children were recruited and divided into three groups: Dyslexic (mean age 8;8), CA control (mean age 8;9), and RL control (mean age 6; 11). They were given a word learning task and a familiar word writing task. It was found that the Dyslexic gro...

The ability to use environmental cues to predict rewarding events is essential to survival. The basolateral amygdala (BLA) plays a central role in such forms of associative learning. Aberrant cue-reward learning is thought to underlie many psychopathologies, including addiction, so understanding the underlying molecular mechanisms can inform strategies for intervention. The transcriptional regu...

Previous studies have demonstrated that N-methyl-D-aspartate (NMDA) receptors and acetylcholine receptors are related to learning and memory in rat and mice. In this study, we examined the effects of MK-801, a non-competitive NMDA receptor antagonist, on learning and memory in zebrafish using a passive avoidance test. We further tested whether or not nicotine, a nicotinic acetylcholine receptor...

Spinally transected rats given legshock whenever one hindleg is extended learn to maintain a flexion response that decreases net shock exposure. Prior exposure to response-independent (noncontingent) shock prevents learning. This behavioral deficit was eliminated by systemic administration of the nonselective opioid antagonist naltrexone (Experiment 1). The deficit was also blocked by intrathec...

Previously we found that Parkinson's disease (PD) patients are impaired in procedural-based category learning when category membership is defined by a nonlinear relationship between stimulus dimensions, but these same patients are normal when the rule is defined by a linear relationship (Maddox and Filoteo, 2001; Filoteo et al., 2005a,b). We suggested that PD patients' impairment was due to a d...