Stimulus pacing affects the activation of the medial temporal lobe during a semantic classification task: an fMRI study
| Autor: | Ruth Seurinck, Karel Deblaere, Ann Tieleman, Pieter Vandemaele, Eric Achten, Guy Vingerhoets |
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| Rok vydání: | 2004 |
| Předmět: |
Adult
Male Cognitive Neuroscience media_common.quotation_subject Stimulus (physiology) Hippocampus Functional Laterality Temporal lobe Stereotaxic Techniques Stimulus modality Text mining Mental Processes Memory Perception Image Interpretation Computer-Assisted medicine Reaction Time Semantic memory Humans media_common Brain Mapping business.industry Brain Middle Aged Classification Magnetic Resonance Imaging Temporal Lobe medicine.anatomical_structure Neurology Categorization Research Design Data Interpretation Statistical Visual Perception Parahippocampal Gyrus Female Nerve Net business Psychology psychological phenomena and processes Parahippocampal gyrus Psychomotor Performance Cognitive psychology |
| Zdroj: | NeuroImage. 26(2) |
| ISSN: | 1053-8119 |
| Popis: | Our purpose was to explore the influence of stimulus pacing in blocked functional MRI studies on the activation pattern elicited by a semantic retrieval task. Twenty-two participants performed both a fixed-paced and a self-paced functional MR imaging experiment in which a semantic categorization (animal/object) task was contrasted with a perceptual (small/capital letter string) categorization task. Group and single-subject ROI analyses were computed. In both the fixed-paced and self-paced experiments, semantic categorization contrasted with perceptual categorization elicited a cerebral network generally accepted to be involved in semantic processing comprising left inferior prefrontal, left lateral temporal, paracingular and right cerebellar areas. Our main finding was that the self-paced stimulus modality additionally yielded significant activation in the medial temporal lobe (MTL) structures including the hippocampus and the parahippocampal gyrus. More elaborative single-subject ROI analyses revealed MTL activation in 86% of the subjects for the self-paced design, but only in 21% of subjects for the fixed-paced design. The discussion focuses on possible explanations for this finding. We conclude that a self-paced as opposed to a fixed-paced semantic retrieval paradigm is able to detect significant MTL activation in groups as well as in single-subjects. This offers opportunities for the application of such a design in clinical practice. |
| Databáze: | OpenAIRE |
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