Quiz 3 Flashcards
1
Q
Premotor areas:
A
- Initiation of output
- Planning of movement sequences of multiple joints
- Left premotor areas are dominant for most individuals.
- Speech (signing)
- Emotional motor output (e.g., smiling)
2
Q
Broca’s area
A
- Functions in speech production
- Controls movements on both sides of face for speech
- For most, performed by left hemisphere
3
Q
Broca’s aphasia (expressive, motor)
A
- Occurs with lesions in Broca’s area
- Nonfluent speech, including difficulty switching from one sound to another smoothly, quickly; Effortful, telegraphic speech (uneven bursts); Disordered grammar, poor naming, poor repetition, paraphasic errors
- Speech often lacks function words (articles, prepositions)
- Comprehension deficit with poor understanding of syntax
- Example: When hearing, “The woman was questioned by the man,” pt may not understand who did questioning
4
Q
Expressive dysprosody
A
Impaired ability to express emotion in language, caused primarily by lesion in homologous areas in right frontal lobe
5
Q
Premotor cortex
A
• Particularly involved with planning movement sequences guided by and in response to visual stimuli (reaching, grasping)
6
Q
Mirror neurons
A
- A neuron that fires both when an animal acts and when the animal observes the same action performed by another.
- In Broca’s area
- A person can recognize an action made by another because the same neural patterns are produced whether s(he) observes or performs that action.
- May be the precursor of language, empathy
- Deficient in individuals with autism
7
Q
Supplementary motor cortex
A
• Plans voluntary movements that are internally generated (willed), rather than in response to stimulus
8
Q
Akinetic mutism
A
Lack of moving or speaking, despite ability to do so
• Lesions on left may cause disruption of speech fluency (e.g., stuttering, poor tonal quality, slowed).
9
Q
Ideomotor apraxia
A
- characterized by the inability to correctly imitate hand gestures and voluntarily pantomime tool use, e.g. pretend to brush one’s hair.
- May be caused by lesions here (as well as in inferior parietal).
10
Q
Cingulate motor cortex
A
• Primarily responsible for motor behaviors in response to emotions and drives (e.g., smiling) - integral part of the limbic system
11
Q
Left hemisphere
A
- More discretely organized than right
- In general, left is better at the kinds of fine details necessary for fine motor sequences, language, logic, arithmetic, algebra.
- Left parietal cortex is better at perceiving details.
12
Q
Left-Hemisphere Dominance
A
- Sequential processing
- Detail analysis
- Temporal analysis
- Language, math (e.g., arithmetic, algebra)
- Motor sequences
- Concentration
- Internal control (according to internal plan and rules)
13
Q
Left-Hemisphere Emotional Response
A
- Dominant for conscious verbal awareness
- Tells us the story of our lives: linear, sequential, analytical, often fabricated (left frontal “interpreter”)
- Left brain injury often causes sadness, conscious awareness of loss, internal preoccupation
14
Q
Left-Hemisphere Dysfunction
A
- Broca’s (expressive) aphasia
- Wernicke’s (receptive) aphasia
- Agraphia – Loss of writing ability
- Alexia – Loss of reading ability
- Acalculia – Loss of math ability
- Apraxia – Loss of ability to perform skilled temporal-sequential movements
15
Q
Right-Hemisphere Dominance
A
- Simultaneous (parallel) processing
- Integration of sensory input
- Leads to integrated body sense
- Visual-spatial processing in parietal cortex
- Better at “gestalts”
- Awareness of extra-personal space
- Throwing & catching a ball, riding a bicycle, dancing
- Insight and intuitive reasoning
- Seeing the forest
- Reading between the lines
- Perceiving & conceiving the overall “big picture”
- Geometry
- Aspects of music
- Social-emotional processing
- External control (responding to environment)
16
Q
Right-Hemisphere Emotional Response
A
- Dominant for social-emotional processing, expression and regulation
- Early maturing in development, role in attachment disorders
- Emotions based on awareness of body reactions
17
Q
Right-Hemisphere Dysfunction
A
Uncontrolled emotions • Conduct Disorder • Sociopathy/Personality Disorders • Autism/Aspergers • Reactive attachment disorder
18
Q
Handedness and Cognitive Organization:
A
- 95% of rt-handers, 70% of left-handers have language in left hemisphere
- 15% of left-handers have language in right hemisphere (anomalous representation)
- 15% of left-handers have language in both.
19
Q
Autonomic Nervous System (ANS)
A
- Involved in subconscious (“automatic”), homeostatic processes to maintain stable internal environment
- Regulates cardiovascular, respiratory, digestive, urinary, reproductive systems
- Neural (autonomic)
- Responses fast to develop but are short- term
- Endocrine
- Responses slow to develop but are prolonged
- Both controlled by CNS (primarily hypothalamus)
- Both affected by emotional factors & sensory input from inside & outside body
20
Q
Sympathetic Nervous System (SNS)
A
- “Fight or flight” - Extreme excitement or exertion cause en masse activation of sympathetic outflow, leading to increased:
- Heart rate
- Blood pressure
- Blood flow to skeletal muscles
- Blood glucose level
- Sweating
- Pupil diameter
- Concurrent activities of decreased:
- Gut motility
- Digestive gland secretion
- Blood flow to abdominal viscera, skin
- Thus, SNS generally acts in a global, nonselective manner
21
Q
Parasympathetic Nervous System (PNS)
A
- “Rest and digest”
* PNS effects are more localized than SNS
22
Q
Meninges
A
- The primary function of the meninges and of the cerebrospinal fluid is to protect the central nervous system.
- 3 membranes surround brain, spinal cord.
- The meninges consist of three layers: the dura mater, the arachnoid mater, and the pia mater.
23
Q
Meningeal Spaces
A
- Epidural space
- Subdural space
- Subarachnoid space
24
Q
Epidural space
A
– Space immediately outside of dura mater
• Spinal cord
• May be injected w/ anesthetics to produce blocks
• Brain
• Contains meningeal arteries & veins
25
Subdural space
* Potential space between dura & arachnoid
| * Laceration of veins in this space produces a subdural hemorrhage.
26
Subarachnoid space
* Contains CSF
* Surrounds entire brain & spinal cord
* Where spinal taps are performed
27
Meningitis:
* Can be serious, even fatal
* Edema, pressure effects, restricted blood flow
* Caused by pathogens in subarachnoid space
* Fever, headache, nuchal (cervical) rigidity
* Neck resists passive flexion
28
Bacterial meningitis:
* Nuchal rigidity, head retraction, fever, headache, nausea/vomiting, seizures, altered consciousness (stupor, lethargy, coma), photophobia
* Increased intracranial pressure (ICP) is the major cause of coma.
* May be an acute fulminant illness that progresses rapidly over few hrs.
* May be a subacute illness that progresses over several days.
29
Viral meningitis:
* Aseptic (no bacteria) meningitis
* Nuchal rigidity, fever, headache, nausea/vomiting, seizures
* Stupor, coma, focal neurologic deficits seldom occur.
30
Encephalitis:
* Herpes simplex encephalitis (HSE)
* Severe damage to temporal lobes (especially hippocampus), VMPFC
* Severe anterograde amnesia, social dysfunction
* Most survivors do not return to normality.
31
Ventricles
* 4 fluid-filled cavities within brain
* Ventricles can serve as landmarks for important nearby structures, thereby providing important clues about the integrity of those structures.
* Caudate nucleus (of BG) lies lateral to anterior horn of lateral ventricle.
* Amygdala lies in front of anterior tip of temporal horn of lateral ventricle.
* Hippocampus lies in floor of temporal horn of lateral ventricle.
32
Choroid plexus
* Secretes CSF (formed from blood) into ventricles
| * Transports nutrients & hormones into ventricles
33
Cerebrospinal Fluid (CSF)
* CSF supports the CNS and protects it against:
* Concussive injury (a shock absorber)
* Swelling
* Dehydration
34
Obstructive hydrocephalus
Accumulation of CSF in ventricles & dilation of ventricles due to blockage of CSF pathways leading to:
• Increased intracranial pressure (ICP) & increased pressure on brain structures, causing:
• Focal neurological sxs (e.g., amenorrhea, incontinence, gait disturbance, dementia)
35
Causes of Obstructive hydrocephalus
* Congenital lesions
* Spina bifida
* Aqueductal stenosis
* Traumatic lesions
* Neoplasms
* Infections (e.g., meningoencephalitis)
36
Prefrontal Cortex
* Plans, organizes most appropriate response – Executive role
* Receives sensory information from posterior lobes
* Receives input from limbic system
* Integrates that information at highest level
37
Executive functions
* Relate to how, if and when an individual will do something
* Include self-control of attention, behaviors, and emotions.
* Dysfunction may include problems with attention, difficulty planning & carrying out plans, impulsivity, emotional lability, and anergia (loss of motivation).
38
Cognitive functions:
* Relate to what & how much an individual knows
| * Usually affects specific abilities (subserved by specific modules)
39
Ventromedial Prefrontal Cortex (VMPFC)
* Controls personal & social reasoning
* Decision making based on awareness of body state, emotions & feedback from social or emotional cues
* Inhibits inappropriate impulses, drives
* Involved in motivation & emotional regulation, including the extinction of conditioned fear
40
pseudodepression
* Depression that is caused by damage to VMPFC
| * Can also occur w/ damage to anterior cingulate
41
Lesions in VMPFC may cause:
* Disinhibition, obsessions
* Decreased awareness of emotional states in self & others
* Expressive dysprosodia
* Decreased empathy, concern for social rules
* Changes in personality & social interactions, termed pseudopsychopathy
42
Orbitofrontal cortex (OFC)
* involved in the cognitive processing of decision-making
* Anosmia (loss of smell) often occurs w/ TBI.
* Compulsions are associated w/ dysfunctional circuit involving OFC/VMPFC, BG, thalamus
* Compulsive aspect of addiction
43
Dorsolateral Prefrontal Cortex (DLPFC)
* The highest cortical area responsible for motor planning, organization, and regulation. It plays an important role in the integration of sensory and mnemonic information and the regulation of intellectual function and action, especially in relation to impulse control.
* DLPFC allows one to act, based on internally generated rules & plans, reflection & judgment, historical information, and abstract themes common to different situations.
* Conceptualizing & maintaining goals
* Helps one focus on task at hand
* Planning overall sequences & contingency planning
* Learning from experience based on previous behavior
* Cognitive flexibility (shifting set)
* Developing strategies for solving complex problems
* Abstract thinking
* Time estimation
* Prospective memory
* Autobiographical memory
* Executive component of working memory
44
Superior Medial Prefrontal Cortex (MPFC)
• Critical for drive, motivation, self-awareness
45
Anterior Cingulate Cortex (ACC)
* Involved with conscious emotion (feelings)
* Monitoring errors, conflict resolution
* The “oops center”
* Selective attention to improve performance & resolve conflicts
46
Ventral portion of ACC
* Plays role in emotions (negative consequences, depression, anxiety, fear).
* Detects mismatch between expectations & real-world outcomes
* Anticipates negative consequences when mistake is made
* Negative emotion accompanying pain
47
Dorsal portion of acc
* Executive attention/monitoring system involved in selective attention and monitoring of performance
* Ensures that processing in other regions is most efficient given current task demands
* Helps to select working memory performed by prefrontal cortex
* Helps posterior cortex to amplify one perceptual module over others
48
ACC & ADHD
* ADHD patients show less activation in ACC when asked to perform tasks requiring selective attention compared to normals.
* Also, in ADHD, there is dysfunction of basal ganglia and prefrontal cortex causing executive disinhibition & cognitive inflexibility, both of which may be due to dsyfunctional executive & skeletomotor loops.
49
Summary of Prefrontal Dysfunction
* Emotion & personality changes are common w/ CNS injury.
* May be direct result of injury or a reaction to being impaired
* Depression (w/ or w/o affective blunting) – The most common
* Anxiety, lability, irritability, impulsivity (including angry outbursts), low frustration tolerance, OCD sxs, emotional hyper-reactivity, apathy
* Sexual changes
* Starting
* Stopping
* Shifting
* Planning, organizing, solving problems
* Profiting/learning from past experiences
50
Prefrontal dysfunction most likely occurs in:
"ALL OF THE ABOVE"
- ADHD patients
- Suicidal patients
- Intermittent explosive disorder
51
Working memory requires a functional prefrontal cortex. (True or False):
True
52
Primary Motor Cortex
Various regions of body are topographically represented by specific neurons within primary motor cortex such that areas of greater dexterity are processed by more neurons.
- Can be modified by experience
Ex: Compared to each other, a soccer player has relatively more motor neurons devoted to feet, and a pianist has relatively more neurons devoted to fingers
53
Pyramidal system
* System of voluntary motor control from primary motor cortex, named after the gross appearance of pyramidal tract as axons decussate in medulla.
* Distinct from extrapyramidal system (EPS) of automatic modulation of motor control performed by basal ganglia
54
Amusia
– Loss of musical abilities (right hem.)
55
Prosopagnosia
– Loss of facial recognition
56
Cerebrospinal Fluid (CSF) for diagnostic purposes:
* Is it clear or cloudy?
* Is there blood?
* What white cells are found?
* Protein and glucose levels?
* Is pressure normal?
