Cerebellum, Motor Control, and Alcohol Effects Flashcards
What is the cerebellum responsible for?
Coordinating voluntary movement and correcting motor errors.
What symptoms arise from cerebellum damage?
Ataxia, intentional tremor, dysmetria, disdiadochokinesis.
What is ataxia?
A lack of voluntary coordination of muscle movements (clumsiness).
What is an intentional tremor?
A shaking that worsens as a person tries to make a precise movement.
What is dysmetria?
Inability to judge distance or scale of movement (overshooting/undershooting).
What is disdiadochokinesis?
Inability to perform rapid alternating movements.
In the ‘CEO’ motor control analogy, what does the motor cortex represent?
The CEO issuing movement commands.
In the same analogy, what does the cerebellum represent?
The middle manager constantly correcting errors.
What part of the brain acts like the ‘factory’ in the motor control analogy?
The muscles executing movement.
What kind of correction does the cerebellum make?
Internal, ongoing correction to refine movements.
What receptor type does alcohol primarily bind to in the brain?
GABA-A receptors.
Where are GABA-A receptors most densely located?
In the cerebellum.
Why does alcohol impair coordination and balance?
It overactivates GABA-A receptors in the cerebellum.
How does alcohol affect the prefrontal cortex (PFC)?
Reduces its ability to do the ‘harder thing’ — lowers inhibition.
What effect does alcohol have on the hippocampus?
Impairs memory formation — contributes to blackouts.
What is nystagmus?
Involuntary eye movement, especially visible during intoxication.
Why is nystagmus a sensitive test for alcohol levels?
It worsens with cerebellar dysfunction, which is highly sensitive to alcohol.
What is long-term depression (LTD) in the context of the basal ganglia?
A synaptic mechanism for refining motor efficiency — opposite of LTP.
