Interactions between dorsal and ventral streams for controlling skilled grasp.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Motor Control

Background:

• The two visual systems hypothesis posits separate brain pathways: the dorsal stream for action control and the ventral stream for object identification.
• Emerging evidence indicates significant interaction between these dorsal and ventral streams, challenging their strict independence.

Purpose of the Study:

• To investigate the crucial role of dorsal and ventral stream interactions in controlling complex, object-oriented hand movements, particularly skilled grasping.
• To explore how anatomical connections between these streams facilitate fine-tuning of grasp precision.

Main Methods:

• Review of anatomical studies reporting direct connections between dorsal and ventral stream areas.
• Analysis of physiological data suggesting increased activity in interconnections with higher grasp precision demands.

Main Results:

• Direct anatomical connections exist between dorsal and ventral visual stream areas.
• The activity of these interconnections increases proportionally with the precision required for grasping an object.

Conclusions:

• Interactions between the dorsal and ventral streams are vital for complex hand movements and skilled grasp.
• The dorsal stream likely accesses ventral stream object identity information for fine-tuning grasps.
• The ventral stream may use dorsal stream feedback to refine object representations during grasping.