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Krauzlis, R. J.

Publications and source records attributed to Krauzlis, R. J..

2 recordsLinked to original sources

Focal disruption of temporal cortex in macaque during midbrain-induced neglect

Spatial neglect is a common clinical syndrome involving disruption of the brains attention-related circuitry, including the dorsocaudal temporal cortex. While neglect is readily modeled in macaques, the absence of evidence for temporal cortex involvement has suggested a fundamental difference from humans. To map the neurological expression of spatial neglect in macaques, we measured attention-related fMRI activity across the cerebral cortex during experimental induction of neglect through reversible inactivation of the superior colliculus. During inactivation, monkeys exhibited hallmark attentional deficits of neglect in tasks using either moving or static stimuli. The behavioral deficits were accompanied by marked reductions in fMRI attentional modulation that were strongest in a small region on the floor of the superior temporal sulcus. Notably, direct inactivation of this mid-STS cortical region caused similar neglect-like spatial attention deficits. These results identify a putative macaque homolog to temporal cortex structures known to play a central role in human neglect.\n\nHighlightsO_LIDuring neglect the mid-STS cortex shows largest reduction in attentional modulation\nC_LIO_LIThe mid-STS cortex is selectively affected with static as well as dynamic stimuli\nC_LIO_LIMid-STS cortex is affected during neglect caused by SC or FEF inactivation\nC_LIO_LIInactivation of mid-STS cortex itself causes neglect without eye movement deficits\nC_LI\n\nIn BriefUsing fMRI in macaques performing attention tasks combined with reversible inactivations, Bogadhi et al. provide causal evidence that a region on the floor of the superior temporal sulcus is a crucial node in the cortical control of covert selective attention and a putative homolog to temporal cortex regions in humans implicated in spatial neglect.

neuroscience

Brain regions modulated during covert visual attention in the macaque

Neurophysiology studies of covert visual attention in monkeys have emphasized the modulation of sensory neural responses in the visual cortex. At the same time, electrophysiological correlates of attention have been reported in other cortical and subcortical structures, and recent fMRI studies have identified regions across the brain modulated by attention. Here we used fMRI in two monkeys performing covert attention tasks to reproduce and extend these findings in order to help establish a more complete list of brain structures involved in the control of attention. As expected from previous studies, we found attention-related modulation in frontal, parietal and visual cortical areas as well as the superior colliculus and pulvinar. We also found significant attention-related modulation in cortical regions not traditionally linked to attention - mid-STS areas (anterior FST and parts of IPa, PGa, TPO), as well as the caudate nucleus. A control experiment using a second-order orientation stimulus showed that the observed modulation in a subset of these mid-STS areas did not depend on visual motion. These results identify the mid-STS areas (anterior FST and parts of IPa, PGa, TPO) and caudate nucleus as potentially important brain regions in the control of covert visual attention in monkeys.

animal behavior and cognition