Lecture 20 Flashcards
(118 cards)
1
Q
How does sleep occur?
A
In cycles
2
Q
What are circadian rhythms?
A
Events that reoccur at interval of about 24 hours
3
Q
What is sleep?
A
A temporary state of unconscious (similar to coma) from which one can wake when stimulated
4
Q
How is sleep characterized?
A
By stereotyped posture (lying down, eyes closed)
5
Q
What is sleep paralysis?
A
Inhibition of muscular activity
6
Q
What effect does sleep have?
A
Restorative
7
Q
Can sleep deprivation be fatal?
A
To experimental animals
8
Q
What may sleep be the time for?
A
Time to replenish such energy sources as glycogen and ATP
9
Q
How might REM sleep consolidate and strengthen memories?
A
By reinforcing some synapses and eliminating others (hippocampus —> cerebral cortex)
10
Q
What does sleep do to growth hormone secretion?
A
It increases it
11
Q
What does an electroencephalogram (EEG) represent?
A
Fluctuations in brain electrical activity in voltage as a waveform of variable frequency and amplitude
12
Q
What does an EEG help in diagnosis of?
A
Diagnosis of degenerative brain disease, metabolic abnormalities, and brain tumors
13
Q
What are brain waves?
A
Rhythmic voltage changes resulting predominantly from synchronized postsynaptic potentials in the superficial layers of the cerebral cortex
14
Q
What is a lack of brain waves a common criterion of?
A
Brain death
15
Q
What is frequency?
A
Number of waves per second
16
Q
What is amplitude?
A
Size of wave
17
Q
What are alpha waves?
A
Awake but resting (eyes closed)
18
Q
What are beta waves?
A
Eyes open and preforming mental tasks
19
Q
What are theta waves?
A
Drowsy or sleepy (adults)/common in children
20
Q
What are delta waves?
A
Deep sleep (adults)
21
Q
How do brain waves change during the different stages of sleep?
A
They change dramatically
22
Q
What are the 2 phases of sleep?
A
REM (rapid eye movement) (eyes oscillate back and forth)
Non-REM (stages N1, N2, N3)
23
Q
What does the early portion of stage 1 sleep produce?
A
Alpha waves, the person is very relaxed yet awake
24
Q
What happens as an individual continues through stage 1 sleep (N1)?
A
There is an increase in that wave activity
25
What happens in stage N2?
State of deep relaxation
Theta waves still dominate the activity of the brain, but they are interrupted by brief bursts of activity known as sleep spindles
Also K complexes are characteristics of this stage
26
What happens in stage N3 or deep sleep?
“Deep sleep or slow-wave sleep”
Heart rate and respiration slow dramatically
Consolidation of memories
27
What stage of sleep does dreaming occur?
REM sleep
28
What does “paradoxical sleep” mean?
High brain activity + lack of muscle tone
29
What is REM antonia?
Motor neurons are not being stimulated
30
What does EEG resemble?
The walking state
Increases T, BP, HR, and respiration
31
What is associated with paralysis of muscle systems?
REM sleep
Except those that make circulation and respiration possible
32
What dreams are in REM sleep?
Vivid and long dreams
Muscle paralysis prevents the person from acting out their dreams
33
What erection and constriction happen in REM sleep?
Penile/clitoral erection
Pupil constriction
34
REM sleep is consolidation of what memories?
Procedural memories
35
When does sleepwalking occur?
In slow wave sleep
36
What is a hypnogram?
Illustrates how an individual moves through the various stages of sleep
37
REM sleep ____ as the night progresses
Increases
Repeat cycle 4-5 times a night
38
What is an example of circadian rhythms?
Sleep-wake cycle
39
What is the body’s master biological clock?
Suprachiasmatic nucleus (SCN)
40
How does the SCN receive direct retinal innervation?
Via the retinohypothalamic tract to ensure its synchronization to day-night cycles
41
What does input from eyes allow the SCN allow for?
To synchronize multiple body rhythms (clocks) with external rhythms of night and day
Sleep, body temp, urine productions hormone secretion, and other functions
42
When is the pineal gland secreted?
In the dark phase
43
What is the function of the lateral hypothalamus?
Light phase (waking)
44
What does melatonin regulate?
Circadian rhythm
Energy balance
45
What does orexin regulate?
Wakefulness
Food intake
46
What do emotional feelings result from?
From interaction between pro frontal cortex (PFC) - diencephalon
47
How does the limbic system categorize emotional experiences?
As either pleasant or unpleasant mental states
48
How does the hippocampus relate to emotion?
Memory consolidation of emotional events
49
How does the hypothalamus relate to emotion?
Influences somatic and visceral motor systems (heart rate and BP increase, hair strands on end, and vomiting)
50
How does the PFC relate to emotion?
Seat of judgement, intent, and control over expression of emotions (how to show those feelings)
51
How does the striatum relate to emotion?
May be involved in avoidance of stimuli paired with aversive events and habit information
52
How does the amygdala relate to emotion?
Receives input from sensory systems and send that information to cortical structures
Role in fear, food intake, sexual behavior, and stress responses
Sends outputs to different brain areas
53
What is cognition?
The range of mental processes by which we acquire and use knowledge
Sensory perception-thought-reasoning-judgment-memory-imagination-intuition
54
What are the 3 functional areas of the cerebral cortex?
1. Primary sensory areas
2. Primary motor areas
3. Association areas
55
What are primary sensory areas?
Receive somatic sensory impulses including the 5 special senses, cutaneous sensation, some proprioception - general senses
Little visceral sensory information is routed to the cortex
56
What are the 5 special senses?
Olfaction (smell)
Gustation (taste)
Equilibrium (balance and body position)
Vision
Hearing
57
What are primary motor areas?
Generate impulses which innervate voluntary skeletal muscles
58
What are association areas?
Cognition (integration of information
59
What does the frontal lobe do?
Helps us think about the world and plan and execute appropriate behaviors
60
What can prefrontal cortex lesions cause?
Personality disorders and socially inappropriate behaviors
61
What does the parietal lobe do?
Helps perceive and attend to stimuli
Controls fine sensation (judgement of texture, weight, size, and shape)
62
What can a lesion of the parietal lobe cause?
Contralateral neglect syndrome: unaware of objects or their own limbs on opposite side of the body
63
What does the temporal lobe do?
Helps identify stimuli
64
What two things can lesions to the temporal lobe cause?
Agnosia:inability to recognize, identify familiar objects
Prosopagnosia: cannot recognize faces or facial expressions
65
What are association areas very close to?
Very close to the primary areas
66
What do primary sensory areas receive?
Sensory impulses (one becomes conscious of a stimulus)
67
What so association sensory areas do?
Integrate the incoming sensory information (and relate it with past experiences
68
How is the primary gustatory cortex regaled to the special senses?
Taste signal are received here in the inferior end of the post central gyrus of the partial lobe
69
How does the primary visual cortex related to the special senses?
This area receives visual signals (occipital lobe)
70
How does the primary auditory relate to the special senses?
Auditory signals are received here in the temporal lobe
71
How does the auditory association area relate to the social senses?
Aids in understanding spoken words
72
What does the primary somatosensory cortex provide?
Awareness of stimulus
73
What does the somatosensory association area make sense of?
Makes cognitive sense of stimulus
74
Where is the somatosensory association area located?
In the roof of the lateral sulcus
75
What is the region of the cerebral cortex related to the general (somatosensory, somesthetic, or somatic) senses?
Primary somatosensory cortex
76
How are the sense distributed?
Over the entire body
77
What is the sensory homunculus?
Diagram of sensory inputs to the primary somatosensory cortex in the parietal lobe
78
What does the sensory homunculus resemble?
A sensory map of contralateral side of the body
79
What is the motor homunculus?
Map of primary motor cortex showing control of skeletal muscles
80
What is the motor homunculus devoted to?
Devoted to a specific area that is proportional to the number of motor units involved in the region’s control
81
What is the amount of cerebral tissue devoted to a given body region proportional to?
Proportional to how richly innervated and sensitive that region is, NOT TO ITS SIZE
82
What are the 3 phases of voluntary movement control?
1. Planing movement
2. Initiating movement
3. Executing movement
83
Where does the intention to contract a muscle begin?
In motor association (premotor) area of frontal lobes
84
What neurons is the program transmitted to?
Neurons of the precentral gyrus of frontal lobes (primary motor area)
85
What neurons are responsible to the execution of the movement?
The alpha motor neurons in the spinal cord
86
What does the cerebellum correct?
Corrects errors in ongoing movements
87
What the happens in the motor association (premotor) area before the second phase?
Neurons compile a program for degree and sequence of muscle contraction required for an action
88
What do the basal ganglia and cerebellum do?
They are large collections of nuclei that modify movement on a minute-to-minute basis
89
How does the basal ganglia and cerebellum interact with the cerebral cortex?
Motor cortex sends information to both structures
Both structures send information right back to the cortex
90
How do you get to the cortex?
Must go through thalamus
91
What is the input of the cerebellum and basal ganglia?
Cerebellum = excitatory
Basal ganglia = inhibitory
92
What does the balance between these two systems allow for?
For smooth, coordinated movement
93
What happens if there is a disturbance in either system?
It will show up as a movement disorder
94
What are the several abilities involved in language?
Reading, writing, speaking, and understanding words
95
Where are the different abilities assigned?
To the different regions of the cerebral cortex
96
What is the angular gyrus (parietal lobe) important for?
Important in the ability to read and write
97
What does the Wernicke’s area, in the left hemisphere, do in the right hemisphere?
Recognizes the emotional content to another person’s speech
98
What does the Broca’s area, in the left hemisphere, do in the right hemisphere?
Affective language area
99
What can lesions in the affective language area cause?
Aprosody: flat emotionless speech
100
How is the emotional aspect of language controlled?
Controlled by regions in the opposite hemisphere that mirror these areas
101
What do lesions of Broca’s area produce?
Aphasia: loss of ability to understand or express speech
Non fluent (Broca’s)
Fluent (Wernicke’s)
102
What do lesions of the right hemisphere cause?
Inability to understand a joke
103
How does a PET scan of the brain during a language task work?
First person reads the words, then they speak them
104
What does the primary auditory cortex do we we intend to speak?
It formulates phrases and transmutes a plan of speech to Broca’s area
105
What does the primary auditory cortex permit?
Permits recognition of spoken and written language
106
What does damage to the primary auditory cortex cause?
Causes loss of language comprehension
107
What does the Broca’s area generate?
Motor program for the muscles of the larynx, tongue, checks, and lips for speaking and for hands when signing
108
What does Broca’s area transmit?
Transmits program to primary motor cortex, which executes it
109
How to the cerebral hemispheres differ?
They differ in structure and function
110
Neither hemisphere is ____, but each is specialized for certain tasks
Dominant
111
What is the left hemisphere known as?
“The categorical hemisphere “
112
What is the right hemisphere known as?
“The representational hemisphere”
113
What is lateralization correlated with?
Handedness
114
What does laterilzation differ with?
Differs with age and sex
115
Children are more resilient to lesions on ____
On one side
116
What happens because males exhibit more lateralization than females?
Males suffer more functional loss when one hemisphere is damaged
117
What are the functions of the left hemisphere?
Sequential and analytical (math and science)
Breaks information into fragments and analyzes it
118
What is the function of the right hemisphere?
Comparison of sights, sounds, smells, and taste
More creative side
