Shared processing of planning articulatory gestures and grasping.

Area of Science:

• Cognitive Neuroscience
• Motor Control
• Speech Production

Background:

• Articulatory gestures and hand actions are thought to be tightly integrated during planning.
• Previous research demonstrated a correspondence between syllable articulation and grip selection (precision vs. power grip).
• This effect was observed during overt articulation, leaving the role of planning integration unclear.

Purpose of the Study:

• To investigate whether the articulation-grip correspondence effect persists without overt speech.
• To explore the underlying mechanisms of integration between planning articulatory and grasping gestures.
• To examine a novel pitch-grip correspondence effect.

Main Methods:

• Experiment 1: Participants silently read syllables while performing grip selection tasks.
• Experiment 2: Participants heard syllables and performed grip selection tasks.
• Behavioral data on response times and accuracy were collected.

Main Results:

• A significant correspondence effect between syllable articulation and grip selection was observed during silent reading and auditory perception.
• Precision grip was faster with tongue-tip syllables, and power grip was faster with tongue-body syllables.
• A pitch-grip correspondence effect emerged: precision grip associated with high pitch, power grip with low pitch.

Conclusions:

• The articulation-grip correspondence effect is driven by shared planning processes, not requiring overt articulation.
• This suggests partially overlapped planning of vocal tract and hand shapes for articulation and grasping.
• The findings offer insights into the neural mechanisms underlying sensorimotor integration and cross-modal correspondences.