Space between cerebral hemispheres and dicenphelon

Bradykinesia

Motor Rigidity

Resting tremor

Postural Instability

> 40 CAG repeats on Chromosome 4

prevalence of 25000

death 10-20 years after disgnosis

Symptoms are: Mood disorders,personality disorders, Dementia, and Chorea

Caused by caudate atrophy and selective degenreation of GABAnergic neurons

Mossy fibers

Climbing fibers

- are both excitatory

provide excitatory collaterals to cerebellar nuclei and cortex

Vestibulocerebellar input

Pontocerebellar input

cuneocerebellar input

spinocerebellar input

reticulocerebellar input

Function of cerebellar

flocculonodular: maintenance of equilibrium and balance

vermix (fastigial nuclei): regulation of posture and programmed movement

paravermis(interposed nuclei): efferens copy

cerebellar cortex (dentate nuclei): planning and programming of skilled movements, cognotive functions

at dicenphelon-mesenphalon junction

medial to internal capsule

superior to cerebral peduncles

inferior to zona incerta

in mesenphalon

ventral to subthalamic nucleus

dorsal to cerebral peduncles

input to subthalamic nucleus

phase difference

time difference

head shadow

reduces impedance mismatch from air to fluid,

amplifies sound

tympatic membrane 17: round window 1

lever action of ossicles 1.3:1

22:1 gain

measurement of impedes is measurement of compliance as a function of pressure

Fluid does not change compliance-Flat line on graph

350000 in USA

In high prevalence countries, MS is second most frequent cause of neurologic disability after trauma

- weakness of limbs

- upper motor neuron symptoms

- optic neuritis

- diplopia

- Paresthesias

- Ataxia

- Bladder and bowel dysfunction

- Euphoria, depression, fatigue

Relapsing/remitting- 85% of onset

secondary progressive- most common

primary progressive- 15% (no attacks but decline)

progressive/repalsing- 5%

- Documentation of 2 or more episodes of symptoms

- symptoms must last >24hrs and present at intervals sperated by a month or more

- one symptom must be present at neurologic exam, the other by MRI or EPs

Lateral medullary syndrome

Wallenberg's syndrome

- vascular lesion to PICA 

-ipsilateral loss of pain,temp. to face

-contralateral loss of pain, temp. to body

- loss of gag reflex, difficulty with speech, swallowing

-horner's syndrome

-vascular lesion to anterior spinal artery

-loss of conscious proprioception, toouch from contralateral side of body

-contralateral upper motor neuron paralysis

-paralysis of ipsilateral tongue

-ipsilateral oculomotor paralysis

-contralateral upper motor paralysis

-vascular lesion affecting cerebral peduncle and oculomotor nerve

-lesion in posterior communicating artery

has no direct connections to CNS, involved in circadian rhythm with respect to release of hormones

receives input from CNS via superior cervical ganglion

receives fibers from the amygdala and contributes to the hypothalamus and ANS.

synapsin(phosphorylated by cadmolin): mobilization

Rab3A: Trafficking

vesicle related: synaptobrevin; synaptotagmin

plasma membrane related: SNAP25,syntaxin; neurexin

GABA

Glycine

AMPA

Nicotinic acetylcholine

Glutamate

choline via choline acetyltransferase to

acetylcholine degraded by acetyl cholinenesterase

to form choline and acetic acid

reticular formation

caudate nucleus

putamen

basal nucleus

septal nuclei

acetylcholinestrase inhibitors

immunosuppresive therapies

plasmapheresis

thymectomy

Dopamine receptors d1 and d2

D1 : stimulate adenyl cyclase activity

D2: Inhibits or no effect on adenyl cyclase activity

substantia nigra

ventral tegmental area

olfactory bulb

hypothalamus

retina

reticular formulation

locus cerulus

nucleus of solitary tract

tryptophan is main precursor, to serotonin via trptophan hydroxylase.

VMAT responsible for uptake into packages, inhibited by reserpine

MAO metabolize serotonin into  5HIAA

superior central nucleus

dorsal raphe group

raphe magnus

raphe pallidus

raphe obscurus

rostral raphe projections are involed in

caudal raphe projections are involved in

- mood and higher functions

- pain and analgesia

-targets PI second messenger system

-blocks inositol phosphate thats converts IP1 to inositol

-allows IP3 to concentrate

interneurons in CNS

primary sensory neurons

pyramidial cells of cerebral cortex

interneurons in CNS

purkinje cells of cerebellar

caudate nucleus

putamen

characteristics of GABAa receptors

inotropic receptors, no second messenger

many modulators (barbituarates)

uses chloride ions

characteristics of GABAb receptors

second messenger receptors

increased k+

decreased ca2+

body, trigone and inferior horns of lateral ventricle

roof of 3rd ventricle

caudal 4th ventricle

(not in anterior, posterior lateral horn or in cerebral aqueduct)

Choroid plexus

ventricular system

subarachnoid space

arachnoid villi

dural venous sinuses

peripheral venous sinuses

total 150ml

3rd and 4th ventricle 2ml

ventricular system 25ml

500ml/day

.35ml/min

turnover time is 3-4 times

increased pressure from ventricular system caused by

increased production

reduced absorption

blockage of circulation

otoconia (calcium crystals) are dislodged from usual position in utricle into semicircular canal causing abnormal endolymph displacement

primary symptom is the sudden onset of severe vertigo and nystagmus that occurs with head movement in the direction of the affected ear.

utricle is for left to right, forward to backward

saccule is for up to down, sagittal plane movement

hair cell stimulation

ampulopetal

ampulofugal

ampulopetal: depolarization, stereocilia bent towards kinocilium

ampulofugal: hyperpolarization, stereocilia bent away kinocilium

3 neuron arc

cn8

interneuron from vestibular nucleus to abducens nucleus

motor neuron to eye muscle

benign paroxysmal position vertigo

nystagmus symptoms

begins after latency period of 10s

increases in amplitude over 10s

decreases in velocity over 30 seconds

lasts for 60s

treated with Epley manuever (80% effective)

lasts minutes to hours 

low frequency hearing loss

roaring tinnitus

gets worse with each attack

endolymphatic hydrops

treatment is diuretics, no salt diet, intratympanic gentamycin injections

-affects men, x-linked

-proximal muscle weakness, atrophy and fasciculations preceded by years of cramping

-affects men in 4th - 5th decade

-androgen insensitivity, big breasts, testicular atrophy, reduced fertility

-castration is treatment

complete androgen insensitivity syndrome

testicular feminization

have testes and produce testorone early, they do no respond to testorone

XY females

agnosia

prosopagnosia

finger agnosia

is a loss of ability to recognize objects, persons, sounds, shapes, or smells while the specific sense is not defective nor is there any significant memory loss

loss of face memory; lesion in inferior temporo-occipital region

lesion in dominant inferior parietal lobe

encode

consolidate

storage

retrieval

present in alcoholics caused by the lack of thiamine in brain

confabulation

antegrade and some retrograde amnesia

damage to anterior thalamus and mamillary bodies

severe antegrade amnesia

normal exam

resolves 24hrs

 cause by migrianes, stroke, seizures

may be repetitive

increased cAMP

activate protein kinase A

- prolongation of depolarization

- stimulates release of more neurotransmitters

-potentiate calcium channels for more action potential

same as short term memory plus Protein kinase A also activates KREB-1

and allows the synthesis of new proteins

dorsolateral for long range planning, problem solving, attention, lesions cause aphathesia

orbitofrontal for regulation of emotions, receives inputs from limbic system, lesions cause disinhibition, inpulsive behaviour

damage to primary visual area: hemifield blindness

damage to primary auditory cortex: no effect unless bilateral

non-dominant parietal hemisphere

left sided neglect in right hemisphere

dsyarthria

aphasia

deficit of speech

deficit of langauge

stria terminalis to hypothalamus

ventral amygdalafugalpathway to thalamus, hypothalamus, basal forbrain and brainstem

caudally splenium of corpus callosum

rostrally anteriro commisure

uncus

entorhinal cortex

amygdala

location: floor of temporal horn

layers: 3 layers archicortex

components: hippocampus, dentate gyrus, subiculum

perforant pathway: ertohinal cortex fibers to dentate granule cells

mossy fibers: dentate gyrus to CA3

schaffer collateral: CA3 to CA1

CA regions of Hippocampus

CA1: next to subiculum, largest, vulnerable to hypoxia

CA3: at genu of dentate gyrus

CA4: in concavity of dentate gyrus