SLIDE #20. A B C D E F SLIDE #12 SLIDE #18 SLIDE #19.

Post on 12-Jan-2016

222 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

Transcript

SLIDE #20

A

B

C

D E

F

SLIDE #12

SLIDE #28

B

A

SLIDE #18

SLIDE #19

SLIDE #23

AB

CD

E

SLIDE #24

A

B

C

D

E

F

G

SLIDE #26

A

B

C

D

AB

C

SLIDE #30

Drawings by Neglect Patients

Extinction?

7. Which of the following statements is FALSE?A. coma follows central herniation involving the diencephalonB. there can be pupillary and eye movement problems following central herniationC. a lesion of the spinal cord does not result in comaD. “locked in” syndrome results from bilateral damage to descending corticospinal and corticobulbar pathways within the basilar (ventral) ponsE. the ARAS is involved in the “locked in” syndrome*****************

17. Which of the following associations is/are correct regarding the four different stages of damage shown here?A. in A there are normal calorics***************B. in B there is decerebrate rigidityC. in C the pupils are meioticD. in D pupils are dilatedE. in A the pupils are constricted*******************8

3. Partial seizures that impair consciousness:A. are called a complex partial seizure*****************B. patient remembers what they do during seizureC. never evolve to tonic-clonicD. do not involve the limbic systemE. none of the above

21. The human circadian pacemaker is located in the:A. supraoptic nucleusB. pinealC. ponsD. pituitaryE. suprachiasmatic nucleus*******************

2. Which of the following nuclei are GABA-ergic?A. LCB. dorsal rapheC. LTD LDT*****************D. PPTE. none of the above

Epilepsy Reading: •child space out  go into a trance, roll his eyes back in his head; had hundreds of seizures daily

•child had cortical dysplasia; an area of grey in the frontal lobe  was up to five times as thick as normal

•medication/drugs successfully controlled the seizures

•the operation removed significant portion of the child's frontal lobe.  Thus, while the seizures were alleviated, the child's future prospects are poor

“LITTLE ALBERT done by John B. Watson was afraid of loud noises (US)-conditioned with a nice white rat- and other neutral things like a Santa Clause maskDREAMING during dreaming=areas of brain=areas areas responsible for emotions, fears and memories are activated---in contrast, areas notably for their role in logic seem to excuse themselves from the party CARTOONS activate VTA-Accumbens-the same reward circuits in the brain that are tickled by cocaineBRITISH ACCENT some stroke don't recover their normal speech and when they only have very, very residual effects left

its heard as an accent LEPTIN-is released by fat cells and tells the brain how much fat is on the bodyECSTACY =release of serotonin, blocks its reuptake, and depletes amount in brain

alpha-relaxed-eyes closed-8-13 cps-relaxed adult

stage 1-theta=4-8 cps-”dreamlike” hypnic jerks

stage 2=12-14 cps-sleep spindles; K complexes-

stage 3/4=1-4 cps-slow wave=delta=orthodox=res--tive in infants-

REM-=like stage 1-paradoxical=active in infants

.

delta=synchronous=high amp.- low freq.

beta-awake-18-25 cps-10-30 microvolts

desynchronous=low amp.- high freq.

WAKING-AROUSED

GABA TIME

DREAM TIME

DR and LC werefiring in NR

REM Sleep-phasic (episodic) tonic (persistant)•rapid eye movements flaccid paralysis•muscle twitches• variable heart rate

.

acetylcholine=keeps you awake

•nicotine= Ach agonist=keeps you awake for those all- nighters

•histamine from caudal hypothal.=wakefullness;

• antihistamine=sedation

•DA and NE=wakefulness via amphetamines and cocaine

•cortisol and CRH result in arousal

•age is major determinant of how we sleep

•newborn sleeps 16-18 hours a day; widely distributed in the 24 hours

Organization of Sleep

5-7% in Stage 1

50% Stage 2

7% Stage 3

11% Stage 4

20-25% REM

•cycles of REM=NREM=each 90-110 minutes

•stages 3 and 4 most prominent early

•REM-lengthens later in night=more intense dreams

ELDERLY: •approximately same % REM (25%) but more napping

•less (or absent) stage 3-4 (the good, delta stuff!)-replaced by Stages 1 and 2

•major sleep problem is insomnia

•more napping

•total hours of sleep same

•sleep apnea (cessation of breathing) and noctural myclonus (periodic leg movements)

Suprachiasmatic nucleus=circadian “@ a day;” lesion SCN = arrhythmic but AMOUNT OF SLEEP DOES NOT CHANGE

light =most impt. for entrainment of biol. clock

live in cave = circadian (“about a day”) rhythms persist (core temp., hormone secretions) no entrainment from normal environment (“Zeitgebers”); no clues to tell him/her the time; does things when one “feels like it”

innate circadian oscillation takes over = “free running period” of between 24.5 and 25.5 hrs.

“cave person” goes to bed one hour later each night

core temp. lowest when he/she goes to sleep because greatest propensity for sleep is at coolest time (try getting up at 5AM)

Neuroendocrine

thyroid stimulating hormone peaks prior to sleep onset; its secretion is inhibited by sleep

growth hormone (GH)-early part of the sleep and its secretion is enhanced by SWS;

prolactin secretion during the middle of the night; may increase REM sleep maximal levels early AM

cortisol levels rise at the end of the sleep or right after waking up=morning arousal—sleep onset is inhibitiory

melatonin from pineal gland-released at night, even if wakeful; nocturnal melatonin release inhibited by light

sleep in the day =no release

Thermoregulation

•brain and body temperature are down-regulated during NREM sleep, particularly SWS--go to sleep feeling somewhat cold and wake up several hours hot

•during REM sleep=decreased ability to regulate body temperature through sweating and shivering.

SOME SLEEP DISORDERS

• CATAPLEXY sudden attacks of REM sleep than can last 5-30 min.due to emotional stimulus, patient falls (loss of muscle tone

exhibit sleep paralysis with hypnagogic hallucinations

hypocretin/orexin-hypothalamus (around [peri] fornix) excite ARAS cells=narcolepsy=fall asleep

2. PERIODIC LIMB MOVEMENTSBabinski-like response –common cause of insomnia

3. RESTLESS LEG SYNDROME• creepy-crawly sensations in legs around bed time• irresistible urge to move legs

1. NARCOLEPSY

•“process S”-longer one stays awake, greater propensity• to sleep•“process C”-circadian=tied to time of day; like clock and does not need to be reset •sleep onset=greatest separation between S and C•“S” occurs around 10-11 PM (for me) and “C” later in night

A. diffuse cortical-thalamic damage: patient exhibits contralateral flexion of arms and extension of legs = DECORTICATE RIGIDITY

small pupils-Horner’s=pressure on hypothalamus (cells project toT1-L2); pupils reactive as CN 3s are OK, but aren’t very big to start with

calorics OK as vestibulo-ocular reflex is fine- as CN 8 gets info. to vestibular nuc.-get DOLL’S EYES-no snap back-lack of cortical input

DOLL’S EYES

B. focal cerebral lesion with central mass effect (pushes on deeper structures) decorticate rigidity = flexion/arms and extension/legs

pupils mid-sized and unreactive=bilateral interruption of the descending autonomics and stretching of CN IIIs.

Calorics/VOR affected-right ear with warm water=movement of the left eye (right vestibular apparatus, right vestibular nuclei, left PPRF and left LR6 are fine). However, the right medial rectus does NOT contract as CN III is shot. No DOLL’S EYES.

C. Lesion lies between superior and inferior colliculi = bilateral extension of upper and lower limbs = DECEREBRATE RIGIDITY

large, un-reactive pupils-CN 3s are shot and descending autonomics headed for T1-L2-pupils are midposition (makes sense if both inputs lost)

Calorics/VOR affected-right ear with warm water=movement of the left eye (right vestibular apparatus, right vestibular nuclei, left PPRF and left LR6 are fine). However, the right medial rectus does NOT contract as CN iii is shot. No DOLL’S EYES

D. Lesion in medulla (yeah level 3!!) kind of “wash” motor-wise

pupils are still in midposition (descending autonomics and CN III are shot!) and fixed (remember, the lesion now runs the length of the brainstem). Since the vestibular nerves/nuclei are now damaged, the VOR does not work.

left cortical mass develops fast and kills CST fibers immediately. Cortical swelling pushes left uncus through tent, resulting a left dilated pupil and right hemipl/Bab (contra to dead CST cells; also can smash left CP). Then opposite cerebral peduncle pushed against free border of tent==bilateral hemipl/Bab.

“locked in”=respiration, sleep cycles, and EEG are fine

Coma Brain Death PersistentVegetative

State

Locked-inSyndrome

Wakefulness - - + +Attention - - - +Memory - - - +

Cognition - - - +EEG Abnormal: wide

range ofabnormalities

ElectrocerebralSilence

Abnormal,slow

Normal

Respiration Variable, maybe depressed

Absent Normal Usuallynormal

Sleep WakeCycle

- - + +

EPILEPSY

THREE SLIDES TO GO!!!

(well, maybe not….have you been sleeping?)

child space out  go into a trance, roll his eyes back in his head had hundreds of seizures dailychild had cortical dysplasia; an area of grey in the frontal lobe  was up to five times as thick as normalmedication/drugs unsuccessfully controlled the seizures the operation removed significant portion of the child's frontal lobewhile the seizures were alleviated, the child's future prospects are good

Partial Seizure- if EEG and behavioral evidence indicate that they begin in a part of the brain limited to one hemisphere

–simple partial = no alteration in awareness-can progress to:

–complex partial = alteration in awareness (2-3 minutes)

simple partial and complex partial can progress to secondarily generalized seizure

Generalized Seizure- when EEG and behavioral evidence indicate they begin bilaterally-always an alteration of consciousness

–tonic = muscle rigidity-either flexion or extension

–tonic clonic (1-2 minutes) grand mal–clonic

–atonic

–absence (petite mal; few seconds)-petit mal

top related