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A functional MRI study of preparatory signals for spatial location and objects.
Neuropsychologia. 2005; 43(14):2041-56.N

Abstract

We investigated preparatory signals for spatial location and objects in normal observers using functional magnetic resonance imaging (fMRI). Activity for attention-directing cues was separated from activity for subsequent test arrays containing the target stimulus. Subjects were more accurate in discriminating a target face among distracters when they knew in advance its location (spatial directional cue), as compared to when the target could randomly appear at one of two locations (spatial neutral cue), indicating that the spatial cue was used. Spatially specific activations occurred in a region at the intersection of the ventral intraparietal sulcus and transverse occipital sulcus (vIPS-TOS), which showed significantly stronger activation for rightward- than leftward-directing cues, while other fronto-parietal areas were activated by the cue but did not show spatial specificity. In visual cortex, activity was weak or absent in retinotopic occipital regions following attention-directing cues and this activity was not spatially specific. In a separate task, subject discriminated a target outdoor scene among distracters after the presentation of spatial neutral cues. There was no significant difference in dorsal frontoparietal activity during the face versus scene discrimination task. Also, there was only weak evidence for selective preparatory activity in ventral object-selective regions, although the activation of these regions to the subsequent test array did depend upon which discrimination (face or place) was performed. We conclude first that under certain circumstances, spatial cues that produce strong behavioral effects may modulate parietal-occipital regions in a spatially specific manner without producing similar modulations in retinotopic occipital regions. Second, attentional modulations of object-selective regions in temporal-occipital cortex can occur even though preparatory object-selective modulations of those regions are absent or weak.

Authors+Show Affiliations

Department of Neurology, Washington University School of Medicine, East Building, 4525 Scott Ave., Box 8225, St. Louis, MO 63110, USA. mau@npg.wustl.eduNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Comparative Study
Journal Article
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

16243051

Citation

Corbetta, Maurizio, et al. "A Functional MRI Study of Preparatory Signals for Spatial Location and Objects." Neuropsychologia, vol. 43, no. 14, 2005, pp. 2041-56.
Corbetta M, Tansy AP, Stanley CM, et al. A functional MRI study of preparatory signals for spatial location and objects. Neuropsychologia. 2005;43(14):2041-56.
Corbetta, M., Tansy, A. P., Stanley, C. M., Astafiev, S. V., Snyder, A. Z., & Shulman, G. L. (2005). A functional MRI study of preparatory signals for spatial location and objects. Neuropsychologia, 43(14), 2041-56.
Corbetta M, et al. A Functional MRI Study of Preparatory Signals for Spatial Location and Objects. Neuropsychologia. 2005;43(14):2041-56. PubMed PMID: 16243051.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - A functional MRI study of preparatory signals for spatial location and objects. AU - Corbetta,Maurizio, AU - Tansy,Aaron P, AU - Stanley,Christine M, AU - Astafiev,Serguei V, AU - Snyder,Abraham Z, AU - Shulman,Gordon L, Y1 - 2005/04/26/ PY - 2004/08/31/received PY - 2005/03/08/revised PY - 2005/03/18/accepted PY - 2005/10/26/pubmed PY - 2006/2/8/medline PY - 2005/10/26/entrez SP - 2041 EP - 56 JF - Neuropsychologia JO - Neuropsychologia VL - 43 IS - 14 N2 - We investigated preparatory signals for spatial location and objects in normal observers using functional magnetic resonance imaging (fMRI). Activity for attention-directing cues was separated from activity for subsequent test arrays containing the target stimulus. Subjects were more accurate in discriminating a target face among distracters when they knew in advance its location (spatial directional cue), as compared to when the target could randomly appear at one of two locations (spatial neutral cue), indicating that the spatial cue was used. Spatially specific activations occurred in a region at the intersection of the ventral intraparietal sulcus and transverse occipital sulcus (vIPS-TOS), which showed significantly stronger activation for rightward- than leftward-directing cues, while other fronto-parietal areas were activated by the cue but did not show spatial specificity. In visual cortex, activity was weak or absent in retinotopic occipital regions following attention-directing cues and this activity was not spatially specific. In a separate task, subject discriminated a target outdoor scene among distracters after the presentation of spatial neutral cues. There was no significant difference in dorsal frontoparietal activity during the face versus scene discrimination task. Also, there was only weak evidence for selective preparatory activity in ventral object-selective regions, although the activation of these regions to the subsequent test array did depend upon which discrimination (face or place) was performed. We conclude first that under certain circumstances, spatial cues that produce strong behavioral effects may modulate parietal-occipital regions in a spatially specific manner without producing similar modulations in retinotopic occipital regions. Second, attentional modulations of object-selective regions in temporal-occipital cortex can occur even though preparatory object-selective modulations of those regions are absent or weak. SN - 0028-3932 UR - https://www.unboundmedicine.com/medline/citation/16243051/A_functional_MRI_study_of_preparatory_signals_for_spatial_location_and_objects_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0028-3932(05)00154-5 DB - PRIME DP - Unbound Medicine ER -