Object and space perception - is it a matter of hemisphere?

Area of Science:

• Neuroscience
• Cognitive Psychology
• Visual Perception

Background:

• The visual system is functionally subdivided into ventral (object perception) and dorsal (space perception) streams.
• Recent models suggest a tripartition of visuospatial functions, necessitating further investigation.
• Understanding these streams is crucial for comprehending visual processing and its neural basis.

Purpose of the Study:

• To investigate the neural underpinnings of object and space perception.
• To examine the roles of different brain regions in visual processing using a large patient sample.
• To validate and refine existing models of visual stream function.

Main Methods:

• Utilized the Visual Object Space Perception (VOSP) battery.
• Employed voxel-based lesion symptom mapping (VLSM) in patients with penetrating traumatic brain injury (pTBI).
• Analyzed a large sample size to ensure robust statistical power.

Main Results:

• Object recognition involves complementary hemispheric roles: right lateral occipital complex for early discrimination, left temporal/frontal regions for complex recognition.
• Space perception relies on the right inferior parietal lobule (IPL) and its network with the right premotor cortex for 2D/3D spatial relationships.
• Confirmed the functional subdivision of the visual system into distinct pathways.

Conclusions:

• The findings support the functional subdivision of the visual system into ventral and dorsal streams.
• Specific neural networks are critical for object and space perception, respectively.
• This research provides novel insights into the specific processes within the dorsal and ventral visual streams.