Diencephalon Flashcards
What are the four main structures of the diencephalon?
Thalamus, hypothalamus, subthalamus, and epithalamus.
What is the primary role of the thalamus?
Processing sensory information and relaying it to the cortex.
Which sensory information bypasses the thalamus?
Olfactory sensory information.
What are the three groups of thalamic nuclei?
Anterior, medial, and lateral groups.
What is the function of the reticular nucleus?
Plays a role in sleep-wake cycles.
What do specific thalamic nuclei do?
Receive sensory signals and project to specific cortical areas.
What is retrograde thalamic degeneration?
Thalamic nuclei degenerate due to lesions in sensory cortical areas.
What is the main function of the hypothalamus?
Controlling the autonomic nervous system (ANS).
What is homeostasis, and how is it maintained?
Physiological adjustments to maintain balance; regulated by the hypothalamus.
What does the pituitary gland regulate?
Hormonal communication and endocrine gland control.
What nuclei are involved in hunger and thirst?
Nuclei in the lateral hypothalamic zone.
What does the suprachiasmatic nucleus control?
The sleep-wake cycle via the pineal gland.
What are the two nuclear groups of the subthalamus?
Subthalamic nucleus and zona incerta.
What is the role of the subthalamic nucleus?
Voluntary movement control.
What two structures make up the epithalamus?
Pineal gland and habenula.
What hormone does the pineal gland secrete?
Melatonin.
What is the function of the habenula?
Plays a role in addiction and nicotine resistance.
What are the three main structures of the basal ganglia?
Caudate nucleus, putamen, and globus pallidus.
What is the role of the basal ganglia?
Influencing voluntary movement control.
What is the direct pathway in the basal ganglia?
Facilitates movement by exciting the motor cortex.
What is the indirect pathway in the basal ganglia?
Inhibits movement by reducing motor cortex activity.
What is the hyperdirect pathway?
Rapidly inhibits movement, acting as an emergency brake.
What is the nigrostriatal pathway?
Connects the substantia nigra and striatum; involves dopamine.
What disease is caused by degeneration of the nigrostriatal pathway?
Parkinson’s disease.
What are the symptoms of Parkinson’s disease?
Rigidity, slowness, tremors, and difficulty initiating movements.
What is Huntington’s disease?
A neurodegenerative disease affecting GABAergic and cholinergic neurons.
What are the symptoms of Huntington’s disease?
Excessive, uncontrollable movements and inability to stop movements.
What type of neurons are lost in Huntington’s disease?
GABAergic and cholinergic neurons.
What is the main function of association thalamic nuclei?
Integrating information from different brain areas.
How does the basal ganglia communicate with the cortex?
Via loops through the thalamus for movement control.
