Spatial Attention Deficits Are Causally Linked to an Area in Macaque Temporal Cortex

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Primate Models

Background:

• Spatial neglect is a common neurological disorder affecting attention, often linked to temporal cortex damage in humans.
• Previous research in macaques has modeled attention deficits but lacked evidence for temporal cortex involvement, suggesting species differences.
• Understanding the neural basis of neglect in non-human primates can provide insights into human brain function.

Purpose of the Study:

• To map the neural correlates of neglect-like attention deficits in macaques.
• To investigate the role of the temporal cortex in spatial attention using functional magnetic resonance imaging (fMRI).
• To identify potential homologous brain regions involved in spatial neglect between macaques and humans.

Main Methods:

• Experimental induction of neglect-like symptoms in macaques via reversible inactivation of the superior colliculus and frontal eye fields.
• Measurement of attention-related fMRI activity across the cerebral cortex during behavioral tasks.
• Correlation of behavioral deficits with changes in fMRI attentional modulation in specific cortical regions.

Main Results:

• Monkeys exhibited hallmark attentional deficits characteristic of spatial neglect during superior colliculus and frontal eye field inactivation.
• Significant reductions in fMRI attentional modulation were observed, predominantly in the superior temporal sulcus (STS).
• Direct inactivation of the mid-STS cortical region replicated neglect-like spatial attention deficits, confirming its role.

Conclusions:

• The study identifies a functional role for the superior temporal sulcus in spatial attention in macaques.
• These findings suggest that the STS in macaques is a potential homolog to human temporal cortex regions implicated in spatial neglect.
• This research bridges a gap in understanding the neural basis of spatial neglect across species.