Term
| Contrast Xray Techniques 103 |
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Definition
| Regular xray no good. This injects a substance that absorbs xrays (contrast) |
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Term
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Definition
| Infusion of radio-opaque dye into cerebral artery to view cerebral circulatory system. Good for localizing vascular damage. |
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Term
| Computed tomography (CT or CAT scan) 103 |
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Definition
| Computer assisted x-ray used to visualize brain of other internal structures. Rotates around head taking many different slices (1000's) of the brain to create cross section. Particularly good at detecting abnormalities such as swelling of an area. |
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Term
| Magnetic resonance imaging (MRI)104 |
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Definition
| 3D images of brains soft tissue, by detecting magnetic activity from nuclear particles in brain molecules. Aligns hydrogen molecules in the h2o. clearer image than ct. |
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Term
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Definition
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Term
| Positron emission tomography 104 |
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Definition
Measure over minutes of average neural activity (rather than structure)in diff. brain regions consumption of sugar glucose, the brains chemical fuel.
Radioactive 2-deoxyglucose (2-DG) is injected usually into carotid artery. |
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Term
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Definition
| Measures over 2 seconds the average neural activity in diff. brain regions, by showing fluctuations in blood oxygen levels. Signal recored called BOLD signal. |
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Term
| Functional MRI 105 (cont) |
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Definition
| Advtges. much sharper than PET, can identify smaller structures. One image provides structural and functional information. No injections |
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Term
Magnetoencephalography (MEG) 106
Temporal resolution (can record fast changes in neural activity) _ Brain image archives |
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Definition
| measures changes in magnetic fields on surface of scalp (produced by underlying neural activity) |
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Term
| Transcranial magnetic stimulation. (TMS) 107 |
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Definition
| Disrupts the activity in an area of the cortex by creating a magnetic field under a coil positioned next to the skull. |
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Term
| (scalp) Electroencephalography (EEG) 107 |
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Definition
| Psycho-physiological recording method - Measured thru electrodes, Waves reflect the sum total of all electrical events in the head, particular wave forms associated with state of consciousness, studies the brains response to specific events (evoked potential), valuable diagnostic tool. |
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Term
| (scalp) Electroencephalography (wave types) 107 |
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Definition
Alpha - regular 8 12 second high amplitude waves, relaxed wakefulness.
Beta - Aroused, stimulated
Theta - Asleep
Delta - Deep asleep |
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Term
| Event-related potential (erp's)108 |
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Definition
| accompanying waves to certain psychological events that occur in the background EEG signal. |
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Term
| Sensory evoked potential (type of ERP) 108 |
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Definition
| the change in cortical EEG signal elicited by a momentary stimulus. (like detecting a whisper in a rock concert) |
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Term
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Definition
| method of reducing the noise in the background EEG |
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Term
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Definition
| small waves, although recorded on scalp originate far away in the sensory nuculi of the brain stem. |
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Term
Muscle tension 109
Electromyogram
(Somatic Nervous System Activity) |
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Definition
procedure for measuring muscle tension. Measures the difference in the voltage between 2 large electrodes placed on the skin above a large muscle.
The Amplitude of the EMG shows the combined level of tension in the underlying muscle. |
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Term
Eye movement (SNS)110
Electooculography (EOG) |
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Definition
| Eye movements are recorded by placing 4 electrodes around the eye. Direction of movement and speed can be determined. |
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Term
Skin Conductance Level (SCL) 110
Skin conductive response (SCR)
(Autonomic Nervous System Activity) |
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Definition
General level of skin conductance associated with a particular situation.
Emotional thoughts and experiences are associated with increases. |
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Term
| Cardiovascular Activity 110 (electrocardiogram)(ECG) or (EKG - german) |
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Definition
| Shows changes in cardiac functions that reflect changes in emotion. |
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Term
| Invasive Physiological Methods 111 |
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Definition
| Fall into 3 categories: lesion, stimulation, recording. SEE NEXT |
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Term
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Definition
| requires an sterotaxic atlas (to locate brain structures. And a stereotaxic instrument To hold the head and electrode holder. |
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Term
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Definition
Aspiration - cortical tissue is drawn off by suction through a glass pipette.
Radio-frequency - sub cortical lesions are made by passing high frequency current thru the target tissue: heat from current destroys tissue. Duration and intensity dependent. |
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Term
| Lesion methods (cont.) 112 |
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Definition
Knife cuts - a device is sterotaxically inserted into brain, blade swings out to make cut.
Phamacologically (neurotoxins)Chemicals destroy only the cell bodies of neurons. 6-OMDA Kills neurons that secrete dopamine and NE, 5-6 DHT seritonin, AF64A - acetycholine (ACH) |
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Term
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Definition
| Reversible lesions, local anesthesia into brain(potassium cloride) spreads depression. Cryogenic blockage (thermolesions)- implant cryoprobe and cool area still cells stop firing. (above 32o)When warm return to normal. |
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Term
Electrical stimulation 113
Recording method |
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Definition
| Developed by Fritsch and Hitzig. Weak pulse current produces firing of neurons near tip of electrode. Stimulation research done prior to lesioning. Stimulation and lesioning are important mapping procedures to address localization issues. Sensoory/motor areas, eating, drinking, emotion centers etc |
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Term
| Invasive recording method 113 |
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Definition
| intracellular unit recording - microelectrode into a neuron measures changes in membrane potential ofa aneuron over time. |
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Term
| Invasive recording (cont) 113 |
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Definition
| Extracellular-unit recording microelectrode positioned near neuron, records firing of that neuron. |
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Term
| Invasive recording (cont)114 |
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Definition
| Multiple unit recording, detects rate of firing of many neurons in general vicinity of electrodes tip. Larger electrode used. |
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Term
| invasive recording (cont)114 |
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Definition
Invasive EEG recording - Implanted electrodes used to record EEG in lab animals, as scalp alone does not provide as clear recordings.
All these are used to study microscopic functions of individual neurons. |
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Term
| Neuropsychological testing 118 |
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Definition
| only small portion of needy brain damaged get due to time consumption. But helps i 3 ways: assisting diagnosis of neural disorders / serve a basis for counseling and caring / provides basis for objectively evaluating effectiveness of treatment and side effects. |
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Term
Single test approach 118
Standardized-test-battery approach 119
Customized battery approach 119 |
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Definition
single - unsuccessful
standard -only marginally better
custom- highly successful |
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Term
| Wechsler Adult intelligence test (WAIS) 119 |
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Definition
| General test of intelligence. Having IQ baseline helps interpretation of subsequent tests. Can draw an inference about neuropsychological dysfunction. |
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Term
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Definition
| Digit span - longest sequence of random digits that can be repeated correctly 50% of the time. See hemispheric damage pg 119... also wisconson card sorting Pg 121 |
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Term
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Definition
| Token test: twenty tokens 2 different shapes. (squares and circles) 5 colors (w,b,y,g,r), 2 sizes (l,s) |
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Term
| Language lateralization 120 |
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Definition
Sodium amytal test- injection
Dichotic listening test - spoken digits |
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Term
Test of perceptual motor function 120
(visuospatial ability) |
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Definition
Block design subtest (WAIS)
Complex figure test
Methods used to assess psychological deficits suspected of brain injury.
Customized battery approach is used by most Neuropsychologists. |
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Term
| general tests (WAIS) 119-120 |
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Definition
| most begin with this, 11 subsets; 6 comprise verbal scale(ex. digit span, infromation); 5 comprise performance scale (block design, object assembly) |
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Term
| general tests (WAIS) 119-120 |
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Definition
| most begin with this, 11 subsets; 6 comprise verbal scale(ex. digit span, infromation); 5 comprise performance scale (block design, object assembly) |
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Term
| General test of Memory deficits 121 |
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Definition
WAIS digit span most common test of verbal short term memory (STM)
WAIS information test (who is the president?) quick way to identify gross deficits in long term memory (LTM) |
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Term
| General test of language 120 |
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Definition
| Token test - see previous... Incorrect responses may indicate damage to the comprehension area |
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Term
| Lateralization of language. 120 |
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Definition
See previous sodium- Amytal
Dichotic listening (kimura) |
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Term
| Specific frontal lobe function 120 |
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Definition
Wisconsin card sorting test- see previous.
frontal lobe damage results in poor adaptation to rule changes( respond to previously correct fashion after it has become incorrect) |
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Term
| Perceptual motor function 121 |
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Definition
LH damage if Subject copies overal config. but omit details
RH damage if subject copies detail but loses overall configuration. |
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