Lecture Notes: Cerebral Cortex Motor Areas

Overview

• Focus on the cerebrum and specifically the cerebral cortex.
• Discussion of the motor areas, which are a part of the cerebral cortex.

Primary Motor Cortex

• Located on the precentral gyrus, just anterior to the central sulcus.
• Responsible for conscious control of precise, skilled, voluntary movements.
• Used in surgical procedures to restore movement, e.g., in tetraplegic patients using electrodes.
• Motor Homunculus: Visual representation showing different body parts' representation in the cortex.
  • High representation: Lips, tongue, thumb, fingers (precise control needed).
  • Low representation: Arm, trunk, hip, knee, foot, toes, genitals (less precise control needed).

Premotor Cortex

• Location: Just anterior to the primary motor cortex.
• Functions as an association area for the primary motor cortex.
• Controls learned, repetitious, or patterned motor skills.
• Coordinates simultaneous or sequential actions.
• Houses procedural memory (e.g., 'muscle memory' like tying shoes).

Broca's Area

• Typically located in the left hemisphere.
• Directs muscle movements involved in speech.
• Important for human communication, a large area of the cerebral cortex is devoted to it.

Frontal Eye Field

• Responsible for directing voluntary movements of the eye.
• Handles saccadic movement and smooth tracking.
• Separate from the visual cortex, which is responsible for vision perception.

Key Takeaways

• The motor areas are crucial for movement coordination and precise control.
• Each area has specialized functions, from motor control to coordinating learned and complex movements.
• The significance of these areas underscores the complexity of brain functions related to movement and speech.

These notes cover the main points discussed in the lecture about the motor areas of the cerebral cortex, providing a structured overview of their functions and significance.