Movement Decomposition in the Primary Motor Cortex

Voluntary Movement: The Primary Motor Cortex

Muscle and movement representations in the primary motor cortex.

What aspects of movement are represented in the primary motor cortex (M1): relatively low-level parameters like muscle force, or more abstract parameters like handpath? To examine this issue, the activity of neurons in M1 was recorded in a monkey trained to perform a task that dissociates three major variables of wrist movement: muscle activity, direction of movement at the wrist joint, and dir...

Goal or movement? Action representation within the primary motor cortex.

Although facilitation of the cortico-spinal system during action observation is widely accepted, it remains controversial whether this facilitation reflects a replica of the observed movements or the goal of the observed motor acts. In the present transcranial magnetic stimulation study, we recorded motor evoked potentials from two hand muscles (first dorsal interosseous and abductor digiti min...

What’s Next? Sequential Movement Encoding in Primary Motor Cortex

Complex actions often can be decomposed into sequences of individual movements. Primate medial motor areas (SMA and pre-SMA) have been shown to be key players in the concert of such sequential actions. In this issue of Neuron, Lu and Ashe show for the first time that neurons in primate M1-the ultimate output stage of cortex-have anticipatory activity related to specific movement sequences. Thes...

Anticipatory Activity in Primary Motor Cortex Codes Memorized Movement Sequences

Movement sequences, defined both by the component movements and by the serial order in which they are produced, are fundamental building blocks of motor behavior. The serial order of sequence production is strongly encoded in medial motor areas. It is not known to what extent sequences are further elaborated or encoded in primary motor cortex. Here, we describe cells in the primary motor cortex...