Exam 7: The Control of Action

The pyramidal motor tract carries signals from the motor cortex of each cerebral hemisphere to ________ side(s)of the spinal cord,whereas the extrapyramidal motor tracts carry signals from various subcortical structures to ________ side(s)of the spinal cord.

Before a movement is initiated,the population vector in the motor cortex has already shifted in the direction of the planned movement.

The excitatory command to contract the biceps muscle of the arm is normally accompanied by an inhibitory command to relax the antagonist triceps muscle.If this inhibitory signal failed to occur,

One reason that lesions to the cerebellum disrupt the eye blink conditioning response is because

Which of the following is NOT a part of the basal ganglia?

Neurons in the spinal cord that can mediate sequences of motor actions even in the absence of external sensory feedback signals are called

In the most general sense,scientists use the term mirror system to refer to a distributed network of neural regions involved in both

The supplementary motor area (SMA)is particularly active during externally guided movements.

With regard to motor cortex,a population vector is the

Although simple reflexes can occur without sensory input,the generation of rhythmic walking movements requires sensory feedback from the environment.

Single-cell recording studies have indicated that the ________ may be especially important in the control of internally guided motor sequences,whereas the ________ may be especially important in the control of externally guided motor sequences.

The term decussation refers to

In the period of time immediately following focal brain injury to the supplementary motor cortex,patients may reach out and grasp objects with the affected arm when they have not been asked to do so,or even when they have been explicitly told not to do so.This is called

Lesions to this region of the cerebellum lead to postural instability and difficulty in keeping one's eyes fixed on a visual object despite head or body movements.

Alpha motor neurons in the spinal cord communicate with muscle fibers by releasing the neurotransmitter acetylcholine,which influences muscle activity by

How is the planning of a complex movement hierarchical? Provide an example.

One major difference between the pyramidal and the extrapyramidal motor tracts is their points of origin.The pyramidal tracts carry messages from ________ to the spinal cord,whereas the extrapyramidal tracts carry messages from ________ to the spinal cord.

Mirror cells are neurons in the ________ cortex that respond when an animal produces a particular movement and when the animal ________.

The fact that the population vector recorded in the motor cortex precedes the corresponding reaching movement indicates that motor cortex activity

Sherrington (1947)surgically disconnected spinal motor neurons from cortical and subcortical motor centers in laboratory animals.Which of the following statements is true about the subsequent motor behavior of these animals?