Chapter 2 Flashcards
What distinguishes neuropsychological assessment from psychological assessment?
Neuropsychological assessment lies in a conceptual frame of reference that takes brain function as its point of departure
Which early instruments for studying the brain function are still in use?
Electrophysiological instruments such as: EEG, EP, ERP
EEG is especially useful in…..
Diagnosing seizure disorders and sleep disturbances, and for monitoring depth of anesthesia
Both EP and ERP…
Can identify hemispheric specialization and assess processing speed and efficiency
Resolution of EEG and MEG
They have both high temporal resolution but neither technique has good spatial resolution
How is electrodermal activity measured and what reflects it?
Electrodermal activity is measured by skin conductance response (SCR) and reflects autonomic nervous system functioning and provides a sensitive and very robust measure of emotional responses and feelings
Electrodermal activity and other autonomic measures such as heart rate, respiration, and pupil dilation have also been used to …
To demonstrate various nonconscious forms as brain processing (example: prosopagnosia)
What snares neuropsychological assessment with psychological assessment?
It relies on many of the same techniques, assumptions, and theories, along with many of the same tests
What reflects Regional cerebral blood flow (rCBF)?
The brain’s metabolic activity indirectly as it changes the magnitude of blood flow in different brain regions
When is it best to use CT and when MRI?
A CT might be best suited for acute head injury when skull fracture and/or bleeding are suspected
MRI (with diffusion tensor imaging) might be the study of choice in the chronic stages of head injury, when the clinician is especially concerned about white matter integrity
PET / SPECT
PET visualizes brain metabolism directly as glucose radioisotopes emit decay signals , their quantity indicating the level of brain activity in a given area
SPECT is similar to PET but less expensive and involves a contrast agent that is readily available
How can you identify the site of seizure onset?
Make a comparison of interictal and ictal SPECT scans
One important clinical application for PET is:
The diagnosis of neurodegenerative diseases.
Many neurodegenerative diseases produce brain alterations that are detectable with PET even when structural neuroimaging fails the show specific abnormalities
How does fMRI works?
Increasing neural activity requires more oxygen: the amount of oxygen delivered by the blood flow actually tends to exceed demand, creating a ratio of oxygenated to deoxygenated blood that is known as the BOLD signal. This signal is highly localizable
Why is fMRI popular in research?
- superior spatial resolution
- fMRI is widely available
- noninvasive
- does not require a medical context for its application
What is identified with the WADA test and electrocortical stimulation mapping?
They identify cerebral language and memory dominance in neurosurgery candidates
Behavior may be conceptualized in terms of three functional systems:
1: cognition - which is the information-handling aspect of behavior
2: emotionality - which concerns feelings and motivation
3: executive functions - which have to do with how behavior is expressed
What are the four major classes of cognitive functions?
1: receptive functions - involve the abilities to select, acquire, classify and integrate information
2: memory and learning - refer to information storage and retrieval
3: thinking - concerns the mental organization and reorganization of information
4: expressive functions - are the means through which information is communicated or acted upon
What is Spearman’s g?
G is considered a general factor for intelligence that contributes to all cognitive abilities, reflecting an individual’s overall tendency to perform more or less well on cognitive tasks
What is perception?
The integration of sensory impressions into psychologically meaningful data
What is sensory reception?
Sensory reception involves an arousal process that triggers central registration leading to analysis, encoding and integrative activities
How do we call impairments in perceptual integration?
Agnosia (literally : no knowledge)
What is associative agnosia?
Failure of recognition that results from defective retrieval of knowledge pertinent to a given stimulus. Here, the problem is centered on memory: the patient is unable to recognize a stimulus despite being able to perceive the stimulus normally
What is apperceptive agnosia?
A disturbance in the integration of otherwise normally perceived components of s stimulus.
Here, the problem is more centered on perception: the patient fails to recognize a stimulus
What is the declarative system? (Explicit memory)
The memory that deals with facts and events and is available to consciousness
What is nondeclarative / implicit memory
Nonconscious memory, related to skills
Declarative memory can be divided into:
- semantic (fact memory)
- episodic (autobiographic memory)
Nondeclarative memory van be divided into:
- item-specific implicit memory
- procedural memory
What are the stages of memory processing?
- registration or sensory memory
- immediate memory
- long term memory
What are the two kinds of registration/sensory memory?
- visual image = iconic memory
- auditory = echoic memory
Subsystems of the working memory
- the phonological loop for language
- the visuospatial sketch pad for visuospatial data
What is rehearsed?
Any repetitive mental process that serves to lengthen the duration of a memory trace.
What is consolidation?
The process of storing information as long term memory
What is anterograde amnesia?
An inability to acquire new information normally
Retrograde amnesia is?
Loss of memory for events preceding the onset of brain injury
What is apraxia?
Disturbances of purposeful expressive functions
What is aphasia?
An acquired disturbance of the comprehension and formulation of verbal messages
