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Stimulus Repetition (stimulus + repetition)

Distribution by Scientific Domains

Psychology	40%

Selected Abstracts

The effect of word repetition on evoked magnetic responses in the human brain

JAPANESE PSYCHOLOGICAL RESEARCH, Issue 1 2000
Takahiro Sekiguchi
Stimulus repetition improves performance on word recognition tasks. We used magnetoencephalography (MEG) to investigate the brain areas associated with this word repetition effect. The participants were eight men and six women. The stimuli were 162 Japanese words each consisting of four katakana letters. The task was to read the words silently and memorize them for a subsequent recognition test. The words were presented one by one and repeated once after eight intervening words. Recordings were taken from bilateral temporal sites of the brain and the responses to the second presentations of the words were compared with those to the first presentations of the same words. Clear magnetic responses were observed in both the left and right hemispheres. In both hemispheres, the responses to the second words were significantly smaller than those to the first words, 250,600 ms after the stimulus onset. Multidipole source analyses showed that the activities were reduced by repetition in the bilateral peri-Sylvian areas, the bilateral medial temporal lobes, and the left angular gyrus. [source]

Lag-sensitive repetition suppression effects in the anterior parahippocampal gyrus

HIPPOCAMPUS, Issue 5 2005
Craig J. Brozinsky
Abstract Single-unit recording studies of monkeys have shown that neurons in perirhinal and entorhinal cortex exhibit activity reductions following stimulus repetition, and some have suggested that these "repetition suppression" effects may represent neural signals that support recognition memory. Critically, repetition suppression effects are most pronounced at short intervals between stimulus repetitions. Here, we used event-related functional magnetic resonance imaging (fMRI) to identify repetition suppression effects in the human medial temporal lobe and determine whether these effects are sensitive to the length of the interval between repetitions. Twenty-one participants were scanned while performing a continuous recognition memory task in which the interval between item repetitions was parametrically varied from 2 to 32 intervening items. We found evidence of repetition suppression in the anterior parahippocampal gyrus, but only when the repetition interval was relatively short. Moreover, bilateral hippocampal regions showed lag-sensitive repetition effects. Our results demonstrate that activity in the human medial temporal cortex, like that of monkeys, exhibits repetition suppression effects that are sensitive to the length of the interval between repetitions. © 2005 Wiley-Liss, Inc. [source]

Neural Correlates of Encoding Predict Infants' Memory in the Paired-Comparison Procedure

INFANCY, Issue 3 2010
Kelly A. Snyder
The present study used event-related potentials (ERPs) to monitor infant brain activity during the initial encoding of a previously novel visual stimulus, and examined whether ERP measures of encoding predicted infants' subsequent performance on a visual memory task (i.e., the paired-comparison task). A late slow wave component of the ERP measured at encoding predicted infants' immediate performance in the paired-comparison task: amplitude of the late slow wave at right-central and temporal leads decreased with stimulus repetition, and greater decreases at right-anterior-temporal leads during encoding were associated with better memory performance at test. By contrast, neither the amplitude nor latency of the negative central (Nc) component predicted infants' subsequent performance in the paired-comparison task. These findings are discussed with respect to a biased competition model of visual attention and memory. [source]

Habituation of auditory evoked potentials in intracranial and extracranial recordings

PSYCHOPHYSIOLOGY, Issue 2 2006
Timm Rosburg
Abstract Effects of stimulus repetition are investigated in short-term habituation experiments. In these experiments, trains of stimuli are applied with longer intervals of no stimulation between the trains. In scalp recordings, an amplitude and latency decrease of the auditory N100 is usually observed at the beginning of the train. This contrasts to a recent finding with intracranial recordings, exhibiting an effect on N100 amplitude, but not on its latency. In the current study, P50 and N100 were simultaneously recorded intra- and extracranially in epilepsy patients. The amplitudes of P50 and N100 decreased in both recordings, whereas the P50 latency was not significantly affected. A latency decrease was revealed for the extracranially recorded N100, but not for the intracranial N100. This dissociation between the intracranial and scalp recordings might be explained by a different sensitivity of the two measurements for N100 generators. [source]