Selectivity for spatial frequency (SF) is one of the fundamental properties of neurons in the visual cortex. Despite the extensive electrophysiological and optical imaging studies on monkeys and cats, the overall cortical organization of SF preference a...

Recent theoretical models based on cellular processes in parahippocampal structures show that persistent neuronal spiking in the absence of stimulus input is important for encoding. The goal of this study was to examine in humans how sustained activity in the parahippocampal gyrus may underlie long-term encoding as well as active maintenance of novel information. The relationship between long-term encoding and active maintenance of novel information during brief memory delays was studied using functional magnetic resonance imaging (fMRI) in humans performing a delayed matching-to-sample (DMS) task and a post-scan subsequent recognition memory task of items encountered during DMS task performance. Multiple regression analyses revealed fMRI activity in parahippocampal structures associated with the active maintenance of trial-unique visual information during a brief memory delay. In addition to a role in active maintenance, we found that the subsequent memory for the sample stimuli as measured by the post-sc...

Individuals with a family history (FH+) of alcohol use disorder (AUD) are 2 to 5 times more likely to abuse alcohol in their lifetimes than individuals with no family history of AUD (FH-) (Spadoni et al., 2008). Even in the absence of heavy alcohol use,...

We experience poor sleep in a new environment; it takes longer time to fall asleep and we are woken frequently from sleep. This temporary sleep disturbance, known as the first-night effect (FNE) in human sleep research, has been regarded as a sleep dist...

We present a functional MRI experiment investigating the neural basis of feature-based attention in humans using the Stroop task. Cortical areas specifically involved in color processing and word reading were first identified in individual participants using independent tests. These areas were then probed during the Stroop task (in which participants must selectively attend to the font color of a word while ignoring the word itself). We found that activation in functionally defined color areas increased during the task relative to a neutral color-naming task while activation in functionally defined word areas decreased. These results are consistent with a biased competition model of feature-based attention in which the processing of attended features is enhanced and the processing of ignored features is suppressed.

Despite the prominence of parietal activity in human neuroimaging investigations of sensorimotor and cognitive processes, there remains uncertainty about basic aspects of parietal cortical anatomical organization. Descriptions of human parietal cortex draw heavily on anatomical schemes developed in other primate species, but the validity of such comparisons has been questioned by claims that there are fundamental differences between the parietal cortex in humans and other primates. A scheme is presented for parcellation of human lateral parietal cortex into component regions on the basis of anatomical connectivity and the functional interactions of the resulting clusters with other brain regions. Anatomical connectivity was estimated using diffusion-weighted magnetic resonance image (MRI)-based tractography, and functional interactions were assessed by correlations in activity measured with functional MRI at rest. Resting-state functional connectivity was also assessed directly in the rhesus macaque latera...

Introduction: The auditory steady state response (ASSR) is one of the indexes of the neural network function of the hearing processing. There are reported that much abnormalities of the gamma band activity in schizophrenia patients. In the functional MR...

Failure of axonal transport from hippocampus to septal nuclei has been implicated in cognitive impairment in Down syndrome (DS) and Alzheimer's disease. Previous studies have shown a decreased retrograde transport of radio-labeled NGF from the hippocamp...

Human amygdala has been implicated in the processing of biologically salient stimuli such as faces and emotional scenes. A number of neuroimaging studies have shown that the presentation of emotionally negative face activated the amygdala more than that...

Craving is a hallmark of drug dependence, including dependence on nicotine. Many studies have examined the neural substrates of cravings elicited by smoking-related cues. Less is known about the neural basis of unprovoked, abstinence-induced cravings, despite the contributions of such cravings to smoking relapse. To fill this gap, we used arterial spin labeled (ASL) perfusion magnetic resonance imaging to characterize the neural substrates of abstinence-induced cravings to smoke. Fifteen chronic smokers were scanned during a resting state on two separate occasions: (1) smoking satiety and (2) abstinence (after ≥12 h of smoking deprivation), in counterbalanced order. Smoking abstinence state (vs satiety) was associated with increased cerebral blood flow (CBF) in anterior cingulate cortex (ACC)/medial orbitofrontal cortex (OFC) and left OFC. Abstinence-induced cravings to smoke were predicted by CBF increases (abstinence minus satiety) in the right OFC, right dorsolateral prefrontal cortex, occipital cortex,...