Search results for " memory"
showing 10 items of 1351 documents
Adult counting is resource demanding.
2004
Several recent studies on both the development of counting and working-memory span tasks have provided results that could be interpreted as ruling out any cognitive resource model for counting. The aim of this study was to test the hypothesis that, even in adults, counting is a demanding task that requires the allocation of cognitive resources. In a first experiment, we asked adults to count arrays of dots while maintaining 5 items in memory (either digits or letters). As we predicted, the concurrent memory load did not increase the rate of errors but induced longer counting times. In a second experiment, we asked adults to count using either the numeric chain or the alphabet while they mai…
Chronometric evidence for memory retrieval in causal conditional reasoning: The case of the association strength effect
2005
According to many models of conditional reasoning, correct responses to the uncertain forms affirmation of consequent (AC) and denial of antecedent (DA) rely on the retrieval of an alternative antecedent from semantic memory. The main prediction issuing from this hypothesis of online retrieval is that the associative strength of the relevant information in long-term memory affects the latency of its retrieval and then of the correct response of uncertainty to AC and DA. This prediction was tested in 64 adults who performed a syllogism evaluation task with familiar causal conditional premises. As predicted, correct responses of uncertainty to AC and DA were not only more frequent but also fa…
The role of the thalamus in amnesia: a tractography, high-resolution MRI and neuropsychological study.
2008
Although it is well established that thalamic lesions may lead to profound amnesia, the precise contribution of thalamic sub-regions to memory remains unclear. In an influential article Aggleton and Brown proposed that recognition memory depends on two processes supported by distinct thalamic and cortical structures. Familiarity is mediated by the mediodorsal (MD) thalamic nucleus and the entorhinal/ perirhinal cortex. Recollection ismediated by the anterior thalamic nucleus (AN), the mamillothalamic tract (MTT) and the hippocampus. The authors also suggested that the lateral dorsal nucleus (LD) may contribute to the thalamic/hippocampus system, thereby implying that the LD may play a role …
The feeling of familiarity for music in patients with a unilateral temporal lobe lesion: A gating study
2015
International audience; Previous research has indicated that the medial temporal lobe (MTL), and more specifically the perirhinal cortex, plays a role in the feeling of familiarity for non-musical stimuli. Here, we examined contribution of the MTL to the feeling of familiarity for music by testing patients with unilateral MTL lesions. We used a gating paradigm: segments of familiar and unfamiliar musical excerpts were played with increasing durations (250, 500, 1000, 2000, 4000 ms and complete excerpts), and participants provided familiarity judgments for each segment. Based on the hypothesis that patients might need longer segments than healthy controls (HC) to identify excerpts as familia…
IQ and the fronto-temporal cortex in bipolar disorder.
2012
AbstractCognitive changes are documented in bipolar disorder (BP). Cortical volume loss, especially in prefrontal regions, has also been reported, but associations between cognition and cortical abnormalities have not been fully documented. This study explores associations between cognitive performance and cortical parameters (area, thickness and volume) of the fronto-temporal cortex in 36 BP patients (25 BPI and 11 BPII). T1-weighted volumetric MRI images were obtained using a 1.5 Tesla scanner. Cortical parameters were measured using surface-based morphometry and their associations with estimated premorbid, current IQ, visual memory, and executive function explored. Premorbid IQ was assoc…
Factors associated with poor functional outcome in bipolar disorder: sociodemographic, clinical, and neurocognitive variables.
2018
Objective: The current investigation aimed at studying the sociodemographic, clinical, and neuropsychological variables related to functional outcome in a sample of euthymic patients with bipolar disorder(BD) presenting moderate-severe levels of functional impairment. Methods: Two-hundred and thirty-nine participants with BD disorders and with Functioning Assessment Short Test(FAST) scores equal or above 18 were administered a clinical and diagnostic interview, and the administration of mood measure scales and a comprehensive neuropsychological battery. Analyses involved preliminary Pearson bivariate correlations to identify sociodemographic and clinical variables associated with the FAST t…
fMRI characterization of visual working memory recognition
2013
Encoding and maintenance of information in visual working memory have been extensively studied, highlighting the crucial and capacity-limiting role of fronto-parietal regions. In contrast, the neural basis of recognition in visual working memory has remained largely unspecified. Cognitive models suggest that recognition relies on a matching process that compares sensory information with the mental representations held in memory. To characterize the neural basis of recognition we varied both the need for recognition and the degree of similarity between the probe item and the memory contents, while independently manipulating memory load to produce load-related fronto-parietal activations. fMR…
Cognitive and Motor Loops of the Human Cerebro-cerebellar System
2010
Abstract We applied fMRI and diffusion-weighted MRI to study the segregation of cognitive and motor functions in the human cerebro-cerebellar system. Our fMRI results show that a load increase in a nonverbal auditory working memory task is associated with enhanced brain activity in the parietal, dorsal premotor, and lateral prefrontal cortices and in lobules VII–VIII of the posterior cerebellum, whereas a sensory-motor control task activated the motor/somatosensory, medial prefrontal, and posterior cingulate cortices and lobules V/VI of the anterior cerebellum. The load-dependent activity in the crus I/II had a specific relationship with cognitive performance: This activity correlated negat…
Altered benzodiazepine receptor sensitivity in alcoholism: a study with fMRI and acute lorazepam challenge.
2007
Previous studies suggested altered sensitivity of the GABA/benzodiazepine receptor system in alcoholic patients. Expanding on these findings, the present functional magnetic resonance imaging (fMRI) study aimed to assess whether a differential modulation of cognitive brain activation by an acute GABAergic drug challenge could be detected in patients with alcoholism. Eight detoxified male patients meeting DSM-IV criteria for alcohol dependence and nine healthy male control subjects were studied with fMRI while performing a 2-back working memory task. The fMRI scans were performed 1 h after intravenous administration of saline and again 1 h after 0.03 mg/kg lorazepam I.V. After saline, a task…
Negative emotional state modulates visual working memory in the late consolidation phase
2020
Although a considerable literature has grown up around the interactions between emotional state and visual working memory (VWM) performance, the mechanism underlying the impact of the negative emotional state on VWM remains unclear. The present study aimed to test whether the influence of emotional state is related to the early phase or late phase of VWM consolidation process. Across three experiments, we found that the negative emotional state did not affect VWM performance when the presentation time of stimuli was short. However, when the presentation time was long, the negative emotional state increased the VWM precision and reduced the VWM number. According to the two-phase model propos…