Hypothalamus
Hypothalamospinal tract axons to the preganglionic neurons can influence what? a. blood pressure, sweating, vasoconstriction, and release of epi and norepi b. central pattern generators and tegmental tract areas c. motor axons d. sensory tracts related to the dorsal columns
A
What part of the hypothalamus gives off inhibitory inputs and is considered heat sensitive? a. anterior hypothalamus b. posterior hypothalamus
A
What are special structures that lack a blood brain barrier and sample blood and CSF to transmit information on the solute concentrations to the hypothalamus? a. arcuate nucleus b. CVO's c. GTO's d. GTFO's
B
What part of the hypothalamus gives off excitatory inputs and is considered cold sensitive? a. anterior hypothalamus b. posterior hypothalamus
B
Where do the hypothalamo-hypophyseal portal system axons travel to? a. VOLT b. median eminence c. central tegmental tract
B
Body function under hypothalamic control. ___________ temperature and febrile response. Intake what nutrients? What cycle is controlled that has to do with reproduction? How is falling asleep affected? How does the eating habits it affects contribute to our mass? Autonomic functon specifically the sympathetic nervous system?
Body. Salt, water and food intake. Sexual cycles, milestones, and sexual orientation. Controls sleep and circadian rhythms. Controls when we are hungry so it controls our weight. Controls response to stress
General function of the hypothalamus a. memory b. breathing c. homeostasis d. executive control
C
Highly specific patterns of autonomic activity direclty related to ongoing needs are generated by different combinations of what? a. hypothalamic nuclei b. autonomic pattern generators c. all of the above
C
Select the correct statement about thhe tuberoinfundibular tract a. they are conected to the thalamus b. they are related to the DLF c. they run from dopaminergic neurons in the arcuate nucleus to the median eminence and regulates prolactin release in anterior pituitary d. all of the above
C
Chemosensory inputs to the hypothalamus
Circumvetnricular organs (CVO's), Hypothalamic chemosensory neurons, and hormone and steroid receptors
What is the first sign of hypothalamic and pituitary tumors? a. inability to use tongues b. problems with internal organ function c. loss of horizontal conjugate gaxe d. tunnel vision
D
Which one of these is not a regulation of the hypothalamus? a. control blood pressure and electrolyte composition b. regulate body temperature c. control energy metabolism d. regulate reproduction e. controls physical and immunological responses to stress f. all of the above are regulations of the hypothalamus
F
What are the primary outputs of the hypothalamus? a. Autonomic and endocrine b. pre-ganglionic authonomic efferent neurons, posterior pituitary and anterior pituitary c. thalamus d. frontal cortex e. all of the above g. A, B
G
Major Anterior Pituitary Hormones
Growth Hormone (GH) Adrenocorticotropic Hormone (ACTH)- stmulates adrenal cortex Follicle-Stimulating Hormone (FSH) Luteinizing Hormone (LH)- stimulate gonads Prolactin (PRL) Thyroid-Stimulating Hormone (TSH, also called Thyrotropin)
What are the three important (CVO's)
VOLT, median eminence, Subfornical organ (SFO)
What happens with lesions to the ventromedial nucleus?
a voracious appetite, obesity and aggressive behavior
Outputs of lateral hypothalamus
basal forebrain (mesolimbic reward system) and amygdala (corticolimbic system)
The lateral hypothalamic area (LHA) in particular can affect the whole ____________ and affects _________ ______________.
brain and complex behavior
CVO's stand for
circumventricular organs
Antidiuretic hormon purpose
controls the blood pressure and fluid volume through the kidney's and blood vessels
Cool sensitive neurons are located in the ________________. Are these neurons excitatory or inhibitory?
dorsomedial posterior hypothalamus, inhibitory
The hypothalamus is divided by the _______________ into medial and lateral zones
fornix
Paraventricular nucleus
glucose sensitive neurons involved in interfactinng endocrine and autonomic systems. Located adjacent to the 3rd ventricle in the medial hypothalamus. Important to releasing vasopressin which is antidiuretic hormone
VOLT (vascular organ of the lamina terminalis)
helps control release of vasopressin and related to osmotic thirst
What hormone is generated from the tuberomammillary nucleus?
histamine
Preoptic Nucleus
judges setpoints, thermoregulation, salt water intake, sleep. Located posterior to lamina terminalis and dorsal and partly anterior to the optic chiasm
Supraoptic Nucleus
laterally just above the optic tract and has responsibility with vasopressin release or antidiuretic hormone release
mammillothalamic tract purpose
links mammillary bodies to the anterior thalamus which is important in limbic circuits
Sexually Dimorphic Nuclei (SDN's)
located in the anterior hypothalamus near the medial preoptic area. Play roles in sexual behavior and responses to sexual stimuli
Suprachiasmatic nucleus
located midline above the optic chiasm. and is responsible for generating circadian rhythms for hormone release (governing body temp., sexual behavior, cycles of activity)
Arcuate Nucleus
located on either side of the 3rd ventricle.and immediately deep to the median eminence. the key player in feeding behavior
What happens if there is damage to the pituitary stalk?
loss of vasopressin production will result in large volumes of weak urinie by the kidney's
Large cells called ___________ affect these two nuclei: _____________ and _______________ synthesize vasopressin and oxytocin and are released by the anterior/posterior pituitary.
magnocellular neurons, paraventricular nucleus and supraoptic nucleus, and are released by posterior pituitary
Histamine function
maintenance of wakefulness, sleep and circadian rhythms
Heat sensitive neurson are located in the _________________. Are these neurons excitatory or inhibitory?
medial preoptic area of the anterior hypothalamus, excitatory
Viscerosensory inputs to the hypothalamus do what and what nucleus do they use?
nucleus of the solitary tract, and sends sensory info from the liver and abdominal viscera via the baroreceptors or chemoreceptors
What is the nucleus that controls thermogenesis and where is it located?
nucleus raphe pallidus (RPa) and is located ventral midline in the medulla
What are the main nuclei of the hypothalamus connected to the autonomic areas?part
paraventricular, arcuate, ventromedial, and lateral hypothalamus
Mammillary bodies
participate in memory functions as apart of the corticohippocampal system
Hypothalamo-hypophyseal tract
pituitary stalk connects the underside of the hypothalamus with the pituitary gland that transmits axons from the paraventricular nucleus and supraoptic nucleus to the posterior pituitary
Tuberomammillary nucleus
posterior hypothalamus that controls all of the histamine release which has an important role in maintenance of wakefulness, sleep and circadian rhythms
How does the hypothalamus directly alter targets in both the paraympathetic and sympathetic nervous system
project directly to parasympathetic preganglionic neurons in the midbrain (edinger-westphal nucleus) pons and medulla (salivatory nuclei, nucleus ambiguus, dorsal vagal nucleus and the sacral cord, via the sympathetic preganglionic neurons in the spinal cord and control the epinephrine and norepinephrine release and finally projecting to autonomic pattern generators like walking in the pons and medulla
Ventromedial nucleus
regulates desire to stop eating
Dorsomedial nucleus
regulating complex integrative control of growth, feeding and maturation, and aspects of reproduction
Tuberal nuclei
release hormones that control release of hormones from anterior pituitary gland. ventromedial, dorsomedial, tuberomammillary and arcuate nuclei
Spinohypothalamic tract
sends mostly thermal and nociceptive from the skin and deep tissues to the hypothalamus via collateral from the spinothalamic tract
The retina sends axonns to the ___________________ nucleus
suprachiasmatic
Korsakoff's syndrome mechanism and structures involved
the fornix and mammillary bodies are degenerated
What is the function of the hypothalamus?
the hypothalamus is responsible for visceral functions such as hunger, thirst, and sex drive. It is the main interface between the nervous system, endocrine system and autonomic nervous system
What are the neural inputs to the hypothalamus?
the retina, the olfactory system, the spinohypothalamic pathway, viscerosensory inputs, prefrontal cortex, insula, amygdala, and the hippocampal formation
The hypothalamus can directly control the outputs of the endocrine and autonomic nervous systems as well as indirectly influencing behavior to maintain set levels of function. A good representation of this is like a ________________.
thermostat
Hypothalamic chemosensory neuron description
they sense circulating levels of metabolities like glucose, long chain fatty acids, osmolality, and temperatures and allow them to change their activity based on the concentration levels
Lateral hypothalmus
wakefulness and a desire to eat and influences behavior with outputs to the basal forebrain and amygdala