Limbic System

Front 1

the limbic system is resbonsible for what?

Back 1

the famous 5 "f's" ,feeding, fighting, feeling, flight, and...

Front 2

emotional expression is more intense on what side of the face indicating they come from which hemisphere?

Back 2

the left side, the right hemisphere

Front 3

the limbic lobe consists of what?

Back 3

the subcallosal area and th subcallosal, cingulate, parahippocampal, hippocampal, and dentate gyri.

Front 4

what are the parts of the limbic system anatomacally?

Back 4

limbic lobe, amygdala, nu accumbens, septal nu, hypothalamus, dorsal thalamus (habenula, anterior nu, and DM), periaqueductal gray, and ventral tegmental nucleus

Front 5

what is the cingulum?

Back 5

association bundles interconnecting the frontal-parietal-temporal limbic cortex

Front 6

what categories of clinical disorders and spectrums are mediated by the limbic system?

Back 6

anxiety DO's, mood DO's, psychosis, substance abuse, memory DO's.

Front 7

describe the track of the papez circuit.

Back 7

begin at the entorhinal area, the gateway into the hippocampus and part of the parahippocampal gy, to the dentate gy through the tract of the fornix to synapse in either the septal nu, anterior thalamic nu, or mammilary body. The septal nu sends axons to another tract, the mamillary bodies send axons to the anterior thalamic nu via the mammilothalamic tract and then the anterior thalamic nu sends axons over the corpus callosum to the cingulate gy which sends axons to the parahippocampal gy and entorhinal area via the cingulum to complete the circuit.

Front 8

what does the papez circuit do?

Back 8

the reverberating circuit focuses, mediates, and intensifies fellings or emotions. It is also a substrate for stress, anxiety, minor depression, and suffereing

Front 9

what would a cingulotomy do?

Back 9

cuts papez circuit and decreases anxiety and suffering

Front 10

what do the stria medullaris thalami fibers convey?

Back 10

from the septal nu (usually stimulated by olfaction or papez) to these fibers to synapse in the habenula of the dorsal thalamus which sends axons to the reticular formation feeding centers to stimulate salivation, swallowing, and secretion of stomach acid

Front 11

in humans, the papez circuit is mainly stimulated by what?

Back 11

neocortex sensory anlyzer, especially vision

Front 12

our feelings or affect will cause certain effects or motor responses which are categorized how?

Back 12

catabolic reactions of flight or flight and anabolic reactions of eating, drinking, and sex (which I thought would be catabolic, but hey...)

Front 13

distinguish between habituation and sensitization of a reflex memory.

Back 13

habituation is reduced response to repetitive stimulus while sensitization is increased response to a repetitive stimulus

Front 14

procedural memory involves what?

Back 14

motor skill memory involving the cerebellum

Front 15

associative memory involves what?

Back 15

the amygdala which involves avoidance responce in the subconscious memory

Front 16

declarative memory involves what?

Back 16

visual-spatial and verbal data processed via the hippocampus

Front 17

on the neuronal level what does reflex habituation involve? reflex sensitization?

Back 17

inactivation of Ca channels so less NT; inactivation of K channels thus more NT release. There is no post synaptic change

Front 18

what mechanisms of memory processing do cause post synaptic changes? What can these mechanisms result in?

Back 18

long term potentiation and long term depression (the correcting mechanism). LTP can result in growth of new synaptic connections (note the dentate gyrus retains the capacity for neurogenesis)

Front 19

what are the two functions of the hippocampus?

Back 19

role in papez circuit and processing short term memory into longterm memory

Front 20

where are the trigger cells for retrieval of long term memory located?

Back 20

in the lateral temporal lobe.

Front 21

a lesion where would result in impairment to form new memories? what is this called?

Back 21

medial temporal lobe (hippocampus). anterograde amnesia

Front 22

a lesion of the lateral temporal lobe will result in what?

Back 22

retrograde amnesia, inability to recall long term memories

Front 23

since some of memory transfer is thought to be cortico-cortical, what structures may be injured bulaterally and still not completely eliminate memory processing?

Back 23

mammy bodies, cingulum, and the fornix

Front 24

what kind of amnesia is wernicke-korsakoff syndrome? what causes it? what may be damaged causing korsakoff's amnestic syndrome? wernicke's encephalopathy (and symptoms)?

Back 24

anterograde (no new long term memories). alcohol abuse and thiamine AKA vit B1. mammy bodies and DM thalamic nu. cerebellum, abducens, oculomotor, and vestibular nuclei resulting in opthalmoplegia, ataxia, and nystagmus

Front 25

what pathology is caused by loss of cholinergic input from Nu basalis of meynert in ventral pallidum? what is the characteristic pathology?

Back 25

alzheimers. Beta amyloid plaques and neurofibrillary triangles (tau protein with excess of phosphate molecules)

Front 26

describe temporal lobe epilepsy AKA psychomotor epilepsy.

Back 26

caused by hippocampal lesion. seizure DO preceded by sensory hallucinations (usually olfactory "uncinate fits") that are characterized by anterograde amnesia, automatisms (automatic execution of associative movements which are usually feeding activities like swallowing via the stria medularis, and perseverations (perpetuation of a motor acivity).

Front 27

what does the amygdala do? where do its fibers project to and what are they called?

Back 27

involved in subconscious and associative learning, alerts and directs attention, and directs hypothalamus and frontal lobe in behavioral responses to instincts and associative learnings esp. related to fear, aggression, food, and sex. The ventral amygdalofugal pathway (associated with the rage reaction) projects to the hypothalamus (over the uncus) and the entorhinal area. The hypothal will then project to the DM of the thal and then to the frontal lobe for decision making. The stria terminalis also projects to the hypothal and entorhinal area, but gets to the hypothal by going posterior to the mammies.

Front 28

what are the male and female differences in terms of the amygdala?

Back 28

left amygdala in females develops strong connections with the limbic cortex while the right amy in men becomes dominant and has strong connections with motor areas.

Front 29

how does the amygdala mediate the rage rxn?

Back 29

via the ventral amygdalofugal pathway. The hypothal lets mediates the immediate undirected "sham rage" while the amy begins to intensify the rage response which will not stop rising until the sham rage is complete

Front 30

what do lesions to the amygdala cause?

Back 30

palcidity (loss of self protective response), loss of associative learning, psychic blindness (type of visual agnosia characterized by a loss of visual awareness coupled with a regression to oral iinspection). Note that placidity also occurs with lesions of the ventral amygdalofugal pathway and/or anterior limbic cortex

Front 31

bilateral ablation of the anterior temporal lobes including the amygdala and the hypothal is called what and what does it result in?

Back 31

kluver bucy syndrome which is characterized by psychic blindness, placidity, deviant pr hypersexual behavior, and anteriograde amnesia

Front 32

loss of pleasure centers is comparable to what?

Back 32

clinical depression: inactivity, non social behavior, irritability, eating and sleep DO's...

Front 33

the septum pellucidum, septal nu, and the nu accumbens are all what?

Back 33

pleasure centers

Front 34

where in the brain is pleasure experienced and what is the chemical basis of pleasure?

Back 34

cortical and subcortical limbic areas including prefrontal and anterior temporal areas. Opoid peptides and monoamines produce feelings of well being and inhibit slow pain

Front 35

where are beta endorphins (opoid peptides)?

Back 35

hypothal and pit. gland

Front 36

enkephalins and dynorphins (opoid peptides) are released where?

Back 36

all along the ventricular system, very close to the slow pain-pleasure axis which includes the septal nu, hypothal, amygdala, intralaminar nu, periaqueductal gray, reticular formation and the substantia gelatinosa of the cord

Front 37

what are the monoamines involved with the limbic system?

Back 37

serotonin, NE, DA, and ach

Front 38

serotonin comes from what nucleus? What are its effect inascending and descending tracts?

Back 38

raphe nucleus. Ascending goes to the medial forebrain bundle and involved in mood elevation, behavior and the sleep wake cycle (note histamine is involved in sleep wake cycle as well). The descending tracts are involved with inhibiting slow pain transmission

Front 39

NE comes from what nuclei? what are its effects in ascending and descending tracts?

Back 39

the locus ceruleus. its ascending tracts go through the medial forebrain bundle and are involved in elevation of attention (arrousal), mood elevation, memory enhancement, regulation of sleep wake cycle. The descending tracts are involved with inhibition of slow pain transmission.

Front 40

DA comes from what nuclei? what are its effects in ascending tract?

Back 40

the ventral tegmental area. Ascending tracts go through the medial forebrain bundle and play a big role in motivation, reward, and enhanced cognition.

Front 41

all drugs of abuse stimulate what pathway?

Back 41

the dopaminergic mesolimbic pathway

Front 42

Ach from the basal nu has what affects? from the ARAS?

Back 42

memory processing and retention. consciousness.

Front 43

why are the individual effects of monamines difficult to study?

Back 43

there are multiple interactions between monoamine centers.

Front 44

the medial forebrain bundle is the main ascending pathway for what from the brainstem? what is its path?

Back 44

for the brainstem ARAS (Ach) and the monoamines. This diffuse pathway will synapse in the hypothal, dorsal thal, septal nu (limbic) and the neocortex (esp. frontal lobe)

Front 45

decreased serotonin is involved with what disorders?

Back 45

depression, aggression, eating and other compulsive disorders, and tourette syndrome

Front 46

decreased NE is involved with what disorders? increased NE?

Back 46

depression. anxiety disorders

Front 47

decreased DA is involved with what disorders of limbic origin? increased DA in mesolimbic area?

Back 47

depression. Schizophrenia

Front 48

Decreased Ach is involved with what disorder?

Back 48

alzheimer's.

Front 49

chronic stress is a major cause of depression. what pathology is associated with these two?

Back 49

inhibited growth and memory processing in the dentate gyrus neurons of the hippocampus (smaller hippo).

Front 50

why do antidepressants take time to have effect?

Back 50

the drugs indirectly stimulate neurons in the dentate gyrus of the hippo to proliferate after a few weeks

Front 51

what are the chemical and physical effects of acute stress (nervous alertness)?

Back 51

the limbic system is stimulated to release NE and the amygdala and the hippocampus are stimulated for enhanced memory and activity (flashbulb memory). The hypothal is then stimulated to activate the sympathetic nervous system and thus the adrenal medulla for release of epi and NE and thus flight or fight

Front 52

chronic stress AKA nervous tirdness has what chemical and physical effects?

Back 52

CRH from cortical neurons affect the limbic system by enhancing the activity of the amygdala and decreasing the activity of the hippo (thus it shrinks like in depressed patients therefore use SSRI's), the hypothal is stimulated and thus CRF to the pit. gland and ACTH in the blood to the adrenal cortex to release cortisol. Note that SSRI's stimulate hippo to regrow via 2nd messengers and brain derived neurotrophic factor which also decreases cortisol peripherally and centrally

Front 53

in chronic stress, what other things have simillar effects to SSRI's?

Back 53

exercise, electroshock, estrogen, Li, microglia proliferation (immune system), and sonic hedgehog protein

Front 54

what signalling peptides are associated with reward?

Back 54

leptin, gherlin, and orexins

Front 55

possible etiology of schizophrenia?

Back 55

excess paring back (degeneration) of prefrontal and anterior temporal areas that occurs in late teens in order to form our judgement centers

Front 56

what are the positive signs and symptoms of schizophrenia? negative?

Back 56

positive means something added to while negative is something subtracted from. Positives are delusions and hallucinations. negatives are impaired judgement and thought processing, flat affect, and low frontal lobe activity during problem solving and decision making

Front 57

what is the pathology and chemical imbalance in schizophrenia?

Back 57

widened sulci in prefrontal area, shallow left superior temporal gyrus, and enlarged ventricles. DA is increased in limbic areas from the ventral tegmental area bc DA activity is diminished in the frontal lobe.

Front 58

older antipsychotic drugs alleviate what schizophrenic symptoms and what is a major side effect?

Back 58

the positive symptoms and may result in tardive dyskinesia which is choreatic movements simillar to huntington's

Front 59

summarize the effects of DA and its nuclei and respective tracts.

Back 59

The substantia nigra sends axons via the nigrostriatal tract to affect movement. The ventral tegmental area will send axons to the mesocortical tract to affect mentation (cognitive function) and the mesolimbic tract to affect mood and motivation (reward)

Front 60

the sensory analyzer part of the insular cortex does what. lesion to it?

Back 60

complex integration of sensory, autonomic, and limbic inputs. Craving and compulsion associated with drug addiction disappears following lesions of the insula

Front 61

what are the three zones of the frontal lobe and their functions?

Back 61

the tertiary zone is the prefrontal cortex that makes decisions and judgements then travels to the secondary zone (premotor cortex) and the primary zone (motor cortex) for motor response

Front 62

a lesion to the right frontal lobe will result in what? left frontal lobe?

Back 62

euphoria (from positive personality centers in the left). fearful, withdrawn, and depressed personality (the negative personality centers in the right remain)

Front 63

bilateral prefrontal deficits and temporal lobe defects are seen in what disorders?

Back 63

schizophrenia, pick's disease, and ADHD (as well as basal ganglia and cerebellar shrinkage)

Front 64

Describe Pick's disease?

Back 64

characterized by pick intracellular inclusion bodies in frontal and temporal lobes. Symptoms include loss of inhibition, rudeness, verbal and sexually aggressive...

Front 65

sensory info comes to the prefrontal cortex via what? limbic info comes to the orbital frontal cortex (prefrontal cortex) via what?

Back 65

superior longitudinal - arcuate fasciculus. Uncinate fasciculus

Front 66

what are the functions of the prefrontal cortex?

Back 66

judgement and decision making, concentration and focus, imagination, creativity, abstract thought, ambition, goal orientation, morality ,religion, and long term adaptation

Front 67

bilateral lesions to the lateral prefrontal lobes results in what?

Back 67

weakening of volitional control, loss of initiative and motivation, loss of concentration, dyscalculia, apathy, impulsive, loss of imagination and creativity, loss of morality and anxiety and guilt, frontal gait apraxia, and frontal release of primitive reflexes (grasping, mouth puckering, and glabellar-tapping on forehead causes multiple eye blinks)

Front 68

bilateral orbital prefrontal cortex lesions will do what?

Back 68

this is major input for limbic system, thus we see disinhibition of primitive drives AKA emotional incontinence, uninhibited irresponsible behavior, euphoric, excessive pointless verbosity, self gratification without regard for social or moral standards, live in present, anosmia (can't smell), and incontinence in medial prefrontal lesions