2 components of epithalamus

function of each?

pineal gland - secrete melatonin

habenular nuclei (relay nuclei)

- afferent input fr stria medullaris thalami

- efferent to interpeduncular nuclei

what does the pineal gland look like on a MRI scan?

location & attachment?

3 contents of pineal gland?

white cone shaped structure (white cuz of brain sand)

lies posterior in diencephalon

attached to 3rd ventricle by pineal stalk

contains:

pinealocytes

glial cells

rich vasculature

what are circumventricular organs?

name 3

pineal body

pituitary gland

area postrema - monitor blood -> can induce vomiting

pineal gland function?

what secrete?

at what time of the day?

endocrine gland involved in seasonal cycles in mammals (circadian rhythms in us)

secretes melatonin

high secretion at night, low in daytime

function of melatonin

in most mammals?

in humans?

what regulates it's secretion?

what's this pathway called?

antigonadotropic effects

more darkness -> less gonadal function

humans: circadian rhythms

- sleep/wake cycle

- light fr retina regulates pineal activity through circuitous pathway

describe circuitous pathway of pineal gland function

light -> retina ->

suprachiasmatic nucleus (hypothalamus) ->

reticular formation (ventrolateral medulla) -> 

intermediolateral neurons (preganglion) in spinal chord ->

superior cervical ganglion ->

pineal gland

1. subthalamic nuclei (STN)

2. Zona Incerta (ZI)

3. Rostral extension of Red Nucleus & Substantia Nigra (SN)

part of basal ganglia circuitry

substantia nigra 

2 parts and where they project to?

pars compacta - striatum

pars reticularis - thalamus

what's the dividing white line in the thalamus called?

what nucleus sits in the anterior region?

what nucleus sits in the medial region?

internal medullary lamina

anterior region - anterior nucleus

medial region - dorsomedial nucleus

specific - receive input from a single sens/motor system & output a a single area of cerebral cortex

non-specific - multiple inputs & outputs

Lateral Geniculate Nucleus (LGN)

type

major input

major output

function

specific

optic tract

primary visual cortex (17)

vision

medial geniculate nucleus

type

major input

major output

function

specific

brachium of inferior colliculus

primary auditory cortex (41,42) 

hearing

VPL - ventral posterior lateral nucleus

type

major input

major output

function

specific

medial lemniscus & spinothalamic

primary somatosensory cortex (3,1,2)

pain, temp, touch, vibr, propr

VPM - ventral posterior medial nucleus

type

major input

major output

function

specific

trigeminothalamic tracts & solitary nucleus

primary somatosensory (3,1,2)

pain, temp, touch, propr from Face

(VL) ventral lateral nucleus

type

major input

major output

function

specific

dentate nucleus, substantia nigra, globus pallidus

primary motor cortex (4)

movement

VA - ventral anterior nucleus

type

major input

major output

function

specific

globus pallidus, substantia nigra

primary motor cortex (4) & premotor cortex (6)

movement

anterior nucleus

type

major input

major output

function

specific

hippocampus (fornix) & mammilothalamic tract

cingulate gyrus

emotion & memory (limbic)

LD - lateral dorsal nucleus

type

major input

major output

function

non-specific

parietal lobe

parietal lobe

unknown

pulmvinar

type

major input

major output

function

non-specific

parietal, occipital, temporal lobes

same thing

vision recognition & attention ??

dorsomedial nucleus

type

major input

major output

function

non-specific

spinothalamic tract, amygdala

prefrontal cortex

emotional response to pain

intralaminar nucleus

type

major input

major output

function

non-specific

multiple cortical areas, reticular formation, cerebellum, basal ganglia, spinothalamic tracts

output - frontal & parietal lobes

alertness & response to pain

which artery gives blood supply to the thalamus?

thalamic pain

where is the damage?

which two nuclei are affected?

what are the symptoms

damage restricted to posterior thalamus

VPL & VPM affected

aching burning pain

resistant to analgesia

thalamic pain accompanied with hemianesthesia & sensory ataxia

may also have paralysis

4 functions of the hypothalamus?

HEAL

homeostasis

endocrine

ANS

limbic 

1. interconnection w/ limbic system pathways

2. outputs on pituitary gland

3. interconnections w/ visceral & somatic nuclein in brainstem & spinal chord

mammilary body

what area of hypothalamus?

function?

destruction causes what?

posterior area of hypothalamus

learning & memory

destruction - impaired memory & emotion drive

posterior nucleus

where located?

what does stimulation cause?

what does destruction cause?

posterior area of hypothalamus

thermoregulation area

stimulation -> heat conservation, vasoconstriction

destruction -> can't thermoregulate, produce poikilothermia (cold blooded animal)

dorsomedial nucleus

what area of hypothalamus?

stimulation causes what?

what is another function?

in the tuberal area of the hypothalamus

stimulation -> obesity (hyperphagia) & rage

some orexin secretion -> wakefullness (loss = narcolepsie)

ventromedial nucleus

where in hypothalamus?

what two parts - functions?

what two hormone-like chemicals cause what?

anterior part - sexually dimorphic (large in female)

superior part - satiety center (tells body i'm full)

leptin, produced by adipose cells, binds here to signal the stomach is full

Grehlin can bind here to induce food uptake

arcuate nucleus

where in hypothalamus?

what hormone released?

what other hormone-like chemical?

stimulation by what can induce food uptake?

some neurons release dopamine (inhibit prolactin by pituitary)

others - neuropeptide Y (NPY) - cause hunger

Grehlin - induce food uptake

paraventricular nucleus & supraoptic

where in the hypothalamus?

function?

what 2 hormones secrete?

what does destruction of it cause?

anterior area of hypothalamus

regulate water balance

secrete oxytocin (during labor) 

vasopressin (ADH)

destruction causes diabetes insipidus (chronic urination -> dehydration)

anterior nucleus

what part of hypothalamus?

what function?

stimulation causes what 2 reactions?

destruction causes what?

anterior part of hypothalamus

thermal regulation

stimulation - drinking & heat dissipation (vasodilation & sweating)

destruction - anhydrosis, hyperthermia

suprachiasmatic nucleus

what part of hypothalamus?

function?

anterior part of hypothalamus

controls biological clocks

endocrine cycles & sleep/wake cycles

sexually dimorphic nuclei of preoptic area of hypothalamus

diff. betw male / female?

function?

what effect in males?

bigger in males

release gonadotropic hormones

male-typical sexual behavior (mounting behavior)

lateral nuclei

where located in hypothalamus?

2 functions?

stimulation causes what?

destruction?

in lateral area

feeding center - regulate food intake

regulate drive states for pleasure & reward

stimulation - eating

destruction - starvation

which arteries supply the areas of the hypothalamus?

1. anterior groups of nuclei

2. tuberal & posterior groups

3. lateral nuclei

1. (AM) anteriomedial arteries (from AcomA & ACA)

2. (PM) posteriomedial group (from PcomA & PCA)

3. (AL) anterolateral aa. (from MCA)