Thank you all who came last week to the first meeting of the Sensorimotor Journal Club; we had quite a lively discussion about some important issues about sensory feedback from motor actions. In particular, we looked at an experiment demonstrating suppression of somatosensation in a finger resulting from intention to move that finger. The question arose whether sensory feedback is always inhibited so non-specifically during movement. This week we’ll discuss some experiments with auditory feedback showing, in some cases, very task-specific suppression of feedback, while in other cases showing little sensitivity. I will present a work from a paper we recently submitted, titled:

Motor induced suppression of auditory cortex

The abstract of which is here:

Sensory responses to stimuli that are triggered by a self-initiated motor-act

are suppressed when compared with the response to the same stimuli

triggered externally, a phenomenon referred to as motor-induced suppression

(MIS) of sensory cortical feedback. Studies in the somatosensory system

suggest that such suppression might be sensitive to delays between the motor

act and the stimulus-onset. A recent study in the auditory system suggests

that such MIS develops rapidly. Here, we characterize the properties of MIS,

by examining the M100 response from the auditory cortex to a simple tone

triggered by a button press. In Experiment 1, we found that MIS develops for

zero delays but does not generalize to non-zero delays. In Experiment 2, we

found that MIS developed for 100 ms delays within 300 trials and occurs in

excess of auditory habituation. In Experiment 3, we found that unlike MIS for

zero-delays, MIS for non-zero delays does not exhibit sensitivity to sensory,

delay or motor-command changes. These results are discussed in relation to

suppression to self-produced speech and a general model of sensory motor

control.