Anatomical correlates for category-specific naming of objects and actions: a brain stimulation mapping study

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Neurolinguistics

Background:

• Object and action word production can be dissociated in aphasia.
• Distinguishing the precise anatomical correlates of object and action naming has been challenging in functional imaging studies.

Purpose of the Study:

• To investigate the overlap and distinctions in cortical neural networks for object- and action-naming processing.
• To identify specific anatomical sites associated with object versus action naming using electrostimulation mapping.

Main Methods:

• Electrostimulation mapping (ESM), a neurosurgical mapping technique, was employed.
• Forty-one patients undergoing brain tumor surgery performed overt naming of object and action pictures under cortical stimulation.
• Interference with naming during stimulation identified language-related cortical sites.

Main Results:

• Out of 633 stimulated sites, 73 (11.5%) showed language interference.
• 44 sites interfered with both object and action naming; 19 were specific to object naming, and 10 to action naming.
• Specific object-naming sites were located in Broca's area (BAs 44/45) and temporal cortex; action-naming sites were in the posterior midfrontal gyrus (BAs 6/9) and Broca's area.

Conclusions:

• The findings suggest a cortical distinction in naming based on conceptual/semantic features.
• Prefrontal/premotor cortex preferentially supports sensorimotor aspects of actions.
• Temporal cortex preferentially supports functional properties of objects.