Diencephalon Flashcards
What are the anatomic groups of the thalamus?
It includes the rostral thalamic group, medial thalamic group, lateral thalamic group, caudal thalamic group, and intralaminar thalamic group.
What nuclei are part of the rostral thalamic group?
Rostral thalamic nucleus
This group is linked to the limbic system.
Name the nuclei in the medial thalamic group.
Medial dorsal nucleus
This nucleus plays a role in cognitive functions.
What nuclei are included in the lateral thalamic group?
Dorsal tier, ventral tier, and ventral caudal groups
What is the function of the ventral rostral nucleus?
It receives afferents from the pallidum and red nucleus and projects to the motor cortex of the frontoparietal lobe.
What sensory system does the lateral geniculate nucleus serve?
Vision
It receives afferents from the optic tract.
What is the role of the medial geniculate nucleus?
It is involved in auditory processing and receives afferents from the caudal colliculus. It projects to the temporal lobe.
Fill in the blank: The _______ nucleus projects to the somesthetic cortex for the head.
Ventral caudal medial
True or False: The ascending reticular activating system (ARAS) maintains a state of wakefulness.
True
What are the clinical signs of lesions in the lateral geniculate nucleus?
Contralateral loss of vision.
What is the function of the hypothalamus?
It regulates visceral motor activity and autonomic nervous system functions.
Name the hypothalamic nuclei in the rostral region.
Supraoptic nucleus, suprachiasmic nucleus, paraventricular nucleus, rostral hypothalamic nucleus, preoptic nuclei, rostral periventricular nucleus.
What is the role of the ventromedial hypothalamic nucleus?
It acts as the satiety center.
What does the mamillothalamic tract connect?
It connects the mamillary nuclei to the rostral thalamic nucleus.
What hypothalamic disease could result in polydipsia?
Diabetes insipidus due to failure of production of ADH.
Fill in the blank: The lateral hypothalamic area is known as the _______.
feeding center
Lesions of the lateral hypothalamic area may result in hyporexia or anorexia
What behavioral changes might occur due to limbic system involvement?
Pacing, circling, aggression, loss of training.
Describe the role of the thalamic reticular system.
It receives inputs from the reticular formation and projects to thalamic nuclei, influencing consciousness.
What is thalamic pain syndrome?
It refers to disturbances in pain perception due to thalamic lesions.
What is the effect of caudal hypothalamus stimulation?
It elicits sympathetic activity.
What is the function of the hypothalamo-adenohypophyseal tract?
It terminates on blood vessels in the tuber cinereum and infundibulum.
True or False: The hypothalamus operates under voluntary control.
False
Hypothalamus operates independently, but may be influenced by higher centers. Consider effect of fear, pain, etc on autonomic functions.
What happens in narcolepsy related to the hypothalamus?
Hypocretin deficiency results in narcolepsy.
Which thalamic group is associated with the limbic system?
Rostral thalamic group
