Limbic System Flashcards

1
Q
  • links a group of functionally related structures that are interposed between the cerebral cortex and the underlying diencephalon
  • hippocampal formation, septal area, and amygdala
  • prefrontal cortex and cingulate gyrus as components within this system
A

limbic system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
  • either directly or indirectly communicate with the hypothalamus or midbrain periaqueductal gray (PAG)
  • modulate the functions normally attributed to the hypothalamus and/or midbrain
A

limbic structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

limbic structures receive inputs from at least two sources

A
  • one or more sensory systems, either directly or indirectly through interneurons in the cerebral cortex
  • brainstem monoaminergic fiber system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The hippocampal formation consists of the ___, ___, and __-

A

hippocampus; dentate gyrus; subicular cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The primary cell type within the hippocampus is the ___, which has both basal and apical dendrites

A

pyramidal cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

extend laterally and slightly in the direction of the ventricular surface

A

basal dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

extend away from the ventricular surface toward the dentate gyrus

A

apical dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
  • superficial layer of the hippocampus
  • fiber layer adjacent to the inferior horn of the lateral ventricle
A

alveus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

situated adjacent to the inferior horn of the lateral ventricle, which contains axons of pyramidal cells that project out- side the hippocampus as well as hippocampal afferent fibers from the entorhinal cortex

A

external plexiform layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

contains basal dendrites and basket cells

A

stratum oriens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

contains the pyramidal cells of the hippocampus

A

pyramidal cell layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

two layers that contain the apical dendrites of the pyramidal cells and hippocampal afferents from the entorhinal cortex

A

stratum radiatum and stratum lacunosum-moleculare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

pyramidal cells of the hippocampus are arranged in a ___

A

C-shaped fashion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

the pyramidal cells situated closest to the subiculum are referred to as the

A

CA1 field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

pyramidal cells located within the hilus of the dentate gyrus

A

CA4 field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

located between the CA1 and CA4 fields

A

CA2 & CA3 fields

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q
  • Collaterals of axons arising from CA3 pyramidal cells project back to the CA1 field
A

recurrent or schaffer collaterals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

CA1 field, the pyramidal cells are highly susceptible to anoxia, especially during periods of temporal lobe epilepsy. This region is referred to as ___

A

Sommer’s sector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The dentate gyrus can also be thought of as a primitive three-layered cortical structure. It is multilayered, and the principal cell type is the ___

A

granule cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

axon of the granule cell, called a ___, makes synaptic contact with pyramidal cells in the CA3 region

A

mossy fiber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

passes from the lateral entorhinal cortex into the molecular layer of the hippocampus

A

lateral perforant pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q
  • medial pathway
  • enters the alveus of the hippocampus after passing through the white matter adjoining the subiculum
A

medial perforant pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
  • passes rostral to the anterior commissure and supplies the septal area
  • topographically organized in that fibers situated near the anterior pole of the hippocampal formation project to the lateral aspect of the lateral septal nucleus, whereas neurons situated more posteriorly in the hippocampal formation project to progressively more medial aspects of this nucleus
  • arises from the hippocampus and subicular cortex
A

precommissural fornix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q
  • innervates the anterior thalamic nucleus, mammillary bodies, and adjoining regions of the medial hypothalamus
  • arises solely from the subicular cortex
A

postcommissural fornix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

enable the hippocampal formation to communicate with widespread regions of neocortex, including areas that receive different modalities of sensory information

A

subicular and entorhinal cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q
  • provides connections between the hippocampus on each side of the brain
  • provide the structural basis by which seizures spread from the hippocampus on one side of the brain to the hippocampus on the other side, allowing for the formation of secondary epileptogenic foci on the side of the temporal lobe contralateral to the site where the primary focus is present
A

commissural component

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

hippocampal formation plays an important role in the control of ___ behavior

A

aggression and rage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

activation of the part of the hippocampal formation closest to the amygdala facilitates ___, whereas activation of the portion closest to the septal pole ___ this form of aggression

A

predatory attack behavior; suppresses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q
  • arises from the subiculum near the temporal pole of hippocampus and projects directly to the ventromedial region of the hypothalamus
  • terminates in the region between suprachiasmatic and arcuate nuclei, which contain hypophysiotrophic hormones that control anterior pituitary function
A

medial corticohypothalamic tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

slow wave of 4–7 Hz

A

theta rhythm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Normally, a rat can learn to enter the correct arm of a Y-maze or the correct series of arms in a more com- plicated maze such as an eight-armed radial maze. Animals sustaining hippocampal lesions consistently fail to approach the correct arm of the maze and consistently make the same or similar kinds of errors

A

spatial learning (spatial memory)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

individual hippocampal cells change their discharge patterns as the animal moves to different parts of the cage or when it is placed in differ- ent arms of a radial maze

A

cognitive map

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q
  • earliest reported disorders
  • memory disorder in which the patient displays amnesia (memory loss) of both anterograde and retrograde memory
  • patient experiences a great deal of difficulty in recalling events in the recent past and handling and retaining new information as well as remembering those events that took place in the distant past
  • associated with the toxic effects of alcohol or from a vitamin B1 (thiamine) deficiency
A

Korsakoff’s syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

memory loss that occurs after hippocampal damage

A

Anterograde memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

refers to loss of memory that occurs before damage to the hippocampus

A

retrograde memory loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

pathway linking the hippocampal formation

A

Papez circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q
  • Patients sustaining hippocampal lobectomies display perseveration of response tendencies and further display
  • patient displays anterograde amnesia, but retrograde amnesia is less severe
  • Such a patient may also have difficulty in reading, in that he is unable to remember a previously read line
A

short-term memory disorder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q
  • hippocampal mechanism that has been proposed as a model for memory consolidation
  • represents a change in synaptic strength as a manifestation of synaptic plasticity. LTP can be produced by stimulating fibers that make excitatory connections with hippocampal pyramidal cells
A

long-term potentiation (LTP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q
  • receives sensory afferent fibers from the medial olfactory stria, monoaminergic systems of the brainstem, hippocampal formation, amygdala, and feed- back signals from the lateral hypothalamus
  • serves principally as a relay of the hippocampal formation to the hypothalamus
A

septal area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

serve to modulate septal neuronal activity, as do the olfactory inputs

A

monoaminergic inputs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q
  • The nuclei of the ___ have wide- spread projections that make synaptic connections with other parts of the limbic system
  • project to olfactory, prefrontal, and anterior cingulate cortices as well as to the amygdala, mammillary bodies, habenular complex, and mediodorsal thalamic nucleus
A

diagonal band of Broca

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

feedback system to the hippocampal formation

A

septal area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q
  • implicated in the control of functions normally attributable to the hypothalamus, such as aggression, rage, autonomic functions, self-stimulation, and drinking behavior
  • lesions of the septal area in rats cause them to be highly irritable, aggressive, easily startled, and very difficult to handle
A

septal rage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

stimulation of the septal area suppresses ___ secretion and adrenal activity in the rat

A

ACTH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

lesions of the septal area facilitate ___ release

A

ACTH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

region that integrates motor and motivational processes associated with the basal ganglia and limbic system, respectively

A

nucleus accumbens

47
Q

major source of dopaminergic fibers to the limbic system and neocortex

A

ventral tegmentum

48
Q

particular interest with respect to the development of Alzheimer’s disease

A

basal nucleus of Meynert

49
Q
  • the presence of neurofibrillary tangles
  • extracellular deposition of the abnormal amyloid protein beta-amyloid cortex plaques in the cerebral cortex
  • cell loss in the basal nucleus and reduced cholinergic content of cortical tissue
A

alzheimer’s disease

50
Q

One approach to combating this disorder involves drug therapy. An example of this approach has been the use of the drug ___

A

Aricept

51
Q

delay development of some of the symptoms of moderate and severe Alzheimer’s disease

A

Namenda (memantine)

52
Q

amygdala contains a cortical mantle called the ___ that provides significant input to the amygdala and is, thus, functionally associated with it

A

pyriform lobe

53
Q

includes mainly the cortical, medial, and medial aspect of the basal nuclei that lie within its dorsal and me- dial aspects

A

corticomedial group

54
Q

includes the lateral, central, and lateral aspects of the basal nuclei

A

basolateral group

55
Q

Communication from the amygdala to the hypothalamus can be achieved by direct or indirect pathways. Direct routes involve the ___ and ___

A

stria terminalis; ventral amygdalofugal pathway

56
Q

___ arises mainly from the corticomedial group of nuclei, and a primary projection of these fibers is directed to the rostrocaudal extent of the preopticomedial hypothalamus.

A

stria terminalis

57
Q

arises mainly from the basolateral complex of amygdala, passes deep to the pyriform cortex, and supplies primarily the lateral hypothalamus and midbrain PAG

A

ventral amygdalofugal

58
Q

hypersexuality, a change in dietary habits, a decrease in anxiety toward fear-producing objects, a tendency to orally explore and contact inedible objects, and visual agnosia

A

KlΓΌver-Bucy syndrome

59
Q

stimulation of the ___ has a powerful, facilitating effect on defensive rage behavior but has an equally potent suppression on predatory attack behavior

A

corticomedial amygdala

60
Q

stimulation of the ___ has just the opposite effects on these forms of aggressive behavior.

A

basolateral region of amygdala

61
Q

Stimulation of the ___ can induce ovulation, whereas transection of the ___ abolishes this response

A

corticomedial amygdala; stria terminalis

62
Q

activation of the ___ facilitates growth hormone release, whereas the ___ inhibits growth hormone release

A

basolateral amygdala; corticomedial amygdala

63
Q

experimental studies have identified circuits that include the amygdala in mediating conditioned fear responses in rodents to ___

A

auditory stimuli

64
Q

difficulties in recognizing stimuli that one would normally characterize as fearful

A

Urbach-Wiethe disease

65
Q
  • unique in that it receives afferent fibers from all regions of the cerebral cortex
  • receives inputs from all brainstem monoaminergic systems and limbic-related structures
A

prefrontal cortex

66
Q

The anterior cingulate gyrus receives inputs from the following areas

A
  • the anterior thalamic nucleus
  • dopaminergic fibers
  • diagonal band of Broca
67
Q

Efferent fibers of the anterior cingulate gyrus project to the ___ and to the ___

A

mediodorsal thalamic nucleus; subicular cortex

68
Q

associated with both emotional and intellectual processes

A

prefrontal cortex

69
Q
  • developed in 1936 by Egaz Moniz
  • controlling human violence and manifestations of psychotic behavior that involved the undercutting of the afferent and efferent connections of the prefrontal cortex
A

prefrontal lobotomy

70
Q

lesions of the ___ lead to an increase in feeding behavior, while stimulation of this region inhibits feeding

A

prefrontal cortex

71
Q

inhibits respiratory movements, changes blood pressure, inhibits gastric motility, and raises the temperature of the extremities

A

electrical stimulation

72
Q
  • recorded at the scalp and sometimes from the surface of the brain during epilepsy surgery
  • measures potential differences between two active electrodes on the scalp or between a scalp electrode and an inactive electrode, which is usually placed behind the ear
  • measures the summation of excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials from the scalp
  • useful in other disorders, such as coma
A

EEG

73
Q
  • very slow, 1-Hz to 3-Hz, synchronous waves that occur under conditions of severe trauma to the brain
  • occur normally for short periods during sleep
A

delta rhythm

74
Q

paroxysmal events in which there is a significant change in the EEG that correlates with a change in behavior and/or consciousness

A

seizures

75
Q

condition in which seizures are recurrent

A

epilepsy

76
Q

time of the occurrence of the seizure

A

ictal period

77
Q

time following the seizure

A

postictal period

78
Q

time between seizures

A

interictal period

79
Q
  • Seizures can be classified into two basic types
A

partial or focal & generalized

80
Q

seizure arises from specific regions of the brain and is limited to one hemisphere

A

partial or focal

81
Q

seizures arise diffusely through- out the brain, causing a loss of consciousness

A

generalized

82
Q

helps to define whether seizures arise from one or more specific areas or whether they develop diffusely

A

EEG

83
Q

Partial seizures can be classified as either

A

simple partial or complex partial seizures

84
Q

do not cause a change in consciousness, but the patient experiences various sensory and motor symptoms, usually not lasting more than 1 to 2 minutes

A

Simple partial seizures

85
Q
  • seizure activity begins locally over the cortex, causing either sensory or motor activity directly corresponding to the homunculus of either the sensory or motor cortex
  • patient experiences a β€œmarch” of sensory or motor activity from muscle to muscle in the same order as the homunculus
A

Jacksonian March

86
Q

speech difficulty that is a less severe form of aphasia

A

dysphasia

87
Q
  • simple partial seizures
  • they provide a warning of the spread of the seizure, causing a complex partial seizure
A

aura

88
Q
  • most common type of seizure
  • psychomotor seizures
  • impairment or loss of consciousness
  • patient may stare and not respond to commands
A

complex partial seizure

89
Q
  • arise diffusely from the cerebral cortex
  • reveal epileptic activity diffusely
A

generalized seizures

90
Q
  • common type of generalized seizure is the generalized
  • β€œconvulsions,” involve a tonic phase or stiffening, followed by a clonic phase in which the extremities contract the agonistic and antagonistic muscles
A

tonic-clonic seizure

91
Q

Prolonged seizure activity or the generation of two or more of these seizures in a row without regaining consciousness

A

status epilepticus

92
Q

very brief (approximately 3–10 seconds long)
patient is unresponsive, commonly described as β€œdaydreaming”

A

Absence seizures

93
Q

very brief and characterized by a rapid muscle jerk accompanied by polyspike and wave complexes, which are also brief

A

Myoclonic seizures

94
Q

found mainly in children with neurologic disorders, consist of a very brief complete loss of muscle tone

A

Atonic seizures,

95
Q
  • patient sits quietly and appears unaware of his surroundings during the time of the seizure (ICTAL PERIOD)
  • patient may appear confused and experience auditory, olfactory, vertiginous, or even gustatory hallucinations
A

partial seizures

96
Q

The postcommissural fornix arises from the

A

Subicular cortex

97
Q

After a neurological examination, a 34-year-old man was diagnosed with temporal lobe epilepsy, the focus of which was estimated to be Sommer’s sector. This region is associated with the

A

CA1 hippocampal field

98
Q

A 63-year-old man was transferred from a psychiatric clinic to the local hospital for a neurological examination because he showed signs of a KlΓΌver-Bucy syndrome

A

Amygdala

99
Q

placidity, hypersexuality, visual agnosia, oral tendencies, and loss of fear of objects that previously produced fear.

A

KlΓΌver-Bucy syndrome

100
Q

A 63-year-old woman was experiencing difficulties in a card-sorting test (as a measure of cognitive function), and failed to accurately perceive the vertical when seated in a tilted chair. A magnetic resonance imaging scan revealed the presence of a lesion in the

A

Prefrontal cortex

101
Q

the patient will not vary her strategy for sorting cards even when asked to do so

A

card-sorting task

102
Q

patient is placed in a tilted chair in the dark and asked to identify the true vertical, she is unable to do so, although normal individuals have little difficulty in doing so

A

perceptual task

103
Q

A 78-year-old man was admitted to a neurological clinic because he was having memory difficulties. The diagnosis was that the patient was experiencing the early stages of Alzheimer’s disease. His disorder most likely involved loss of or damage to neurons in the

A

Basal nucleus of Meynert

104
Q

Short-term memory processes, modulation of hypothalamic processes, in particular, emotional and endocrine functions

A

Hippocampal formation

105
Q

Temporal lobe epilepsy, short-term memory disorders; aggressive and rage behavior, possible endocrine dysfunctions

A

Hippocampal formation

106
Q

Modulates aggression and rage and other functions of the hypothalamus; also serves as a relay of hippocampal formation to hypothalamus

A

Septal area

107
Q

Emotional disorders, including rage and aggression, and related functions of hypothalamus

A

septal area

108
Q

Fear, regulation of aggression and rage, functions associated with hypothalamus, including feeding, endocrine and autonomic processes

A

Amygdala

109
Q

Emotional disorders, e.g., aggression, rage, and loss of fear; disruption of other functions associated with hypothalamus, e.g., endocrine functions and eating disorders; temporal lobe epilepsy

A

Amygdala

110
Q

Cognitive, autonomic, and emotional processes, including the control over aggression and rage

A

Prefrontal cortex

111
Q

Loss of control over emotional processes, autonomic functions, flat personality, memory and intellectual deficits

A

Prefrontal cortex

112
Q

Nucleus accumbens mediates mood states; basal nucleus of Meynert of substantia innominata is cholinergic and is believed to mediate memory functions of cerebral cortex

A

Basal forebrain: nucleus accumbens, substantia innominata

113
Q

Dysfunctions of nucleus accumbens may be associated with addictive behavior; damage to basal nucleus of Meynert is associated with Alzheimer’s disease

A

Basal forebrain: nucleus accumbens, substantia innominata