An attentional mechanism for selecting appropriate actions afforded by graspable objects

Area of Science:

• Cognitive Neuroscience
• Motor Control
• Human Action Planning

Background:

• Objects can afford multiple actions, necessitating mechanisms to select the appropriate motor program.
• Attentional mechanisms are known to modulate sensory processing but their role in inhibiting motor programs is less understood.

Purpose of the Study:

• To investigate whether attentional mechanisms inhibit competing motor programs during action selection.
• To determine if visual attentional effects, specifically suppressive surround effects, manifest in motor behavior.

Main Methods:

• Participants performed a speeded key press task to categorize rotated door handles presented successively.
• Response hand compatibility with the graspable part of the door handles was manipulated (compatible vs. incompatible).
• Handle orientations were varied (identical vs. slightly dissimilar) to elicit suppressive surround effects.

Main Results:

• Compatible responses were faster than incompatible responses when handle orientations were identical.
• Compatible responses were slower than incompatible responses when handle orientations were slightly dissimilar, indicating a suppressive surround effect.
• This suppressive surround effect, typically seen in visual attention, was observed behaviorally in motor control.

Conclusions:

• An attentional mechanism actively inhibits competing motor programs, preventing erroneous actions.
• Suppresssive surround effects demonstrate a shared neural mechanism between visual attention and motor preparation.
• This finding bridges sensory processing and action planning, highlighting a fundamental brain function.