fMRI reveals a preference for near viewing in the human parieto-occipital cortex
| Autor: | Derek J. Quinlan, Jody C. Culham |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Adult
Male Eye Movements Cognitive Neuroscience Motion Perception Posterior parietal cortex Vergence Reflex Pupillary Choice Behavior Luminance Macaque Orientation Parietal Lobe biology.animal Cortex (anatomy) Image Processing Computer-Assisted medicine Humans Attention Dominance Cerebral Brain Mapping Depth Perception medicine.diagnostic_test biology Distance Perception Accommodation Ocular Anatomy Convergence Ocular Sulcus Magnetic Resonance Imaging medicine.anatomical_structure Neurology Female Occipital Lobe Visual angle Functional magnetic resonance imaging Psychology Psychomotor Performance |
| Zdroj: | NeuroImage. 36:167-187 |
| ISSN: | 1053-8119 |
| DOI: | 10.1016/j.neuroimage.2007.02.029 |
| Popis: | Posterior parietal cortex in primates contains several functional areas associated with visual control of body effectors (e.g., arm, hand and head) which contain neurons tuned to specific depth ranges appropriate for the effector. For example, the macaque ventral intraparietal area (VIP) is involved in head movements and is selective for motion in near-space around the head. We used functional magnetic resonance imaging to examine activation in the putative human VIP homologue (pVIP), as well as parietal and occipital cortex, as a function of viewing distance when multiple cues to target depth were available (Expt 1) and when only oculomotor cues were available (Expt 2). In Experiment 1, subjects viewed stationary or moving disks presented at three distances (with equal retinal sizes). Although activation in pVIP showed no preference for any particular spatial range, the dorsal parieto-occipital sulcus (dPOS) demonstrated a near-space preference, with activation highest for near viewing, moderate for arm’s length viewing, and lowest for far viewing. In Experiment 2, we investigated whether the near response alone (convergence of the eyes, accommodation of the lens and pupillary constriction) was sufficient to elicit this same activation pattern. Subjects fixated lights presented at three distances which were illuminated singly (with luminance and visual angle equated across distances). dPOS displayed the same gradient of activation (Near > Medium > Far) as that seen in Experiment 1, even with reduced cues to depth. dPOS seems to reflect the status of the near response (perhaps driven largely by vergence angle) and may provide areas in the dorsal visual stream with spatial information useful for guiding actions toward targets in depth. |
| Databáze: | OpenAIRE |
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