Neuroscience: Motor Areas and Anatomy Quiz

Located in the frontal lobe, in front of the precentral sulcus, this gyrus is responsible for higher-order cognitive functions like planning, working memory, and decision-making.

A deep groove that separates the superior frontal gyrus from the middle frontal gyrus. This sulcus helps divide the frontal lobe into different functional areas.

This area of the brain is responsible for controlling voluntary movements of the hand. Damage to this region can result in weakness or paralysis of the hand on the opposite side of the body.

A deep groove that marks the boundary between the frontal lobe and the parietal lobe. This sulcus is important for motor control and sensory processing.

Damage to specific areas within the motor-hand area can cause weakness in the hand on the opposite side of the body. This is because the motor cortex controls voluntary movements on the contralateral (opposite) side of the body.

A region in the brain responsible for controlling voluntary movements of the mouth and tongue, crucial for speech and swallowing.

The space between the brain's hemispheres, containing myelinated nerve fibers that carry signals between different regions.

A large bundle of white matter found in the brain, responsible for connecting the cortex with lower brain regions.

A large bundle of white matter fibers that radiate from the internal capsule to the cerebral cortex. It's the main pathway for information between the brain and the rest of the body.

A simplified map of the human body within the brain. The larger areas on the map correspond to regions of the body with finer motor control.

The motor fibers responsible for controlling the face and tongue.

The motor fibers responsible for controlling the hands.

A set of nerve pathways that carry signals from the cerebral cortex to the brainstem.

The area in the brain responsible for controlling voluntary movements of the face, arms, and legs.

The path taken by nerve fibers connecting the motor cortex to the spinal cord, responsible for carrying signals that initiate voluntary movement.

Blood vessels in the motor cortex are delicate and prone to damage. High blood pressure can cause rupture, leading to paralysis or weakness in the affected body parts.

Damage to a lower motor neuron in the spinal cord results in muscle weakness or paralysis, known as flaccid paralysis. This occurs because the signal from the brain cannot reach the muscle, leading to a loss of control.

The final common pathway for voluntary movements. They receive signals from the brain and transmit them to skeletal muscles.

A useful analogy to understand lower motor neuron lesions: Imagine a broken electric fan that makes noise when turned on but doesn't spin. The problem is localized to the fan's motor (the lower motor neuron), not the power source (the brain) or the wiring (upper motor neurons).

Lesions at the level of the lower motor neuron result in muscle atrophy because the muscle is no longer receiving signals to contract and maintain its size.

Lower motor neuron lesions are characterized by decreased or absent reflexes, as the signal from the brain is interrupted, leading to a lack of reflex response.

The corticospinal tract carries signals from the motor cortex to the spinal cord for voluntary movement.

The corticospinal tract fibers are organized in a specific way in the internal capsule and crus cerebri. The arm fibers are located anterior to the leg fibers.

The corticospinal tract decussates, meaning most of its fibers cross over to the opposite side at the cervicomedullary junction.

The corticospinal tract controls muscles that are essential for life, such as chewing and swallowing.

The crossed fibers of the corticospinal tract descend as the lateral corticospinal tract, which primarily controls limb movements.

The uncrossed fibers of the corticospinal tract descend as the anterior corticospinal tract, which controls axial muscles.

The anterior corticospinal tract can potentially compensate for damage to the lateral corticospinal tract, allowing some movement even in cases of paralysis.

The corticospinal tract is an upper motor neuron pathway, meaning that it originates in the brain and carries signals to lower motor neurons.

Damage to the corticospinal tract can result in weakness, paralysis, or spasticity.

When evaluating a patient with a movement disorder, it is important to determine if the problem is due to a muscle or nerve issue, and if it's an upper or lower motor neuron problem.

The point where nerve pathways from the brain cross over to the opposite side of the body.

A specific type of lesion that primarily affects the brain and its structures.

A principle used in diagnosing, meaning the simplest explanation is often the most likely.

Assessing pupils, eye movements, response to pain, and breathing patterns to pinpoint the location of a neurological problem.

The way a neural signal's location becomes disrupted by a lesion, depending on if it occurs before or after the signal crosses in the brain.

This refers to the sensation of where the body is positioned, a sense lost if a lesion affects the appropriate path

A common method used to pinpoint where a neurological issue is localized.