Chapter 5 - The Research Methods of Biopsychology Flashcards
contrast x-ray techniques
x-ray techniques that involve the injection, into one compartment of the body, of a substance that absorbs x-rays either less than or more than surrounding tissue
cerebral angiography
a contrast x-ray technique for visualizing the cerebral circulatory system by infusing a radio-opaque dye into the cerebral artery
computed tomography (CT)
a computer assisted x-ray procedure that can be used to visualize the brain and other internal structures of the living body
positron emission tomography (PET)
technique for visualizing brain activity, usually by measuring the accumulation of the radioactive fluorodexyglucose (FDG) in active areas in the brain
ligands
ions or molecules that bind to other molecules under investigation
Magnetic resonance imaging (MRI)
a structural brain imaging procedure in which high-resolution images are constructed from the measurement of waves that hydrogen atoms emit when they are activated by radio-frequency waves in a magnetic field
> high spatial resolution
spatial resolution
the ability to detect and represent differences in spatial location
functional MRI (fMRI)
magnetic resonance imaging technque for inferring brain activity by measuring increased oxygen flow into particular areas
> Nothing has to be injected
> provides both structural and functional information
> spatial resolution is better
> produce three-dimensional images of activity over the entire brain
BOLD signal
the blood-oxygen-level- dependent signal
temporal resolution
ability of a recording technique to detect differences in time (to pinpoint when an event occurred)
Diffusion tensor imaging
MRI technique that is used for identifying major tracts
Transcranial magnetic stimulation (TMS)
technique that can be used to turn off an area of human cortex by creating a magnetic field under a coil positioned next to the skull
> temporarily turns off part of the brain while the effects of the disruption on cognition and behavior are assessed
Transcranial direct current stimulation (tDCS)
technique used to stimulate (“turn on”) an area of the cortex by applying an electrical current through two electrodes placed directly on the scalp
electroencephalography
electroen- cephalogram (EEG) is a measure of the gross electrical activ- ity of the brain. It is recorded through large electrodes by a device called an electroencephalograph (EEG machine), and the technique is called electroencephalography
alpha waves
regular, 8- to 12-per-second, high-amplitude waves that are associated with relaxed wakefulness
event-related potentials (ERPs)
accompanying EEG waves are generally referred
sensory evoked potential
change in the
cortical EEG signal elicited by the
momentary presentation of a sensory
stimulus
signal averaging
method used to reduce the noise of the background EEG
P300 wave
the positive wave that occurs about 300 milli- seconds after a momentary stimulus that has meaning for the subject
far-field potentials
small waves, they originate far away in the sensory nuclei of the brain stem
magnetoencephalography (MEG)
measures changes in magnetic fields on the surface of the scalp that are produced by changes in underlying patterns of neural activity
Electromyography
usual procedure for measuring muscle tension, resulting record is called an electromyogram (EMG), EMG activity is usually recorded between two electrodes taped to the surface of the skin over the muscle of interest
electrooculography (eye movement)
Electrooculography is based on the fact that a steady potential difference exists between the front (positive) and back (negative) of the eyeball
> when the eye moves, a change in the electrical potential between electrodes placed around the eye can be recorded
skin conductance level (SCL) and the skin conductance response (SCR)
SCL: a measure of the background level of skin conductance associated with a particular situation
SCR: the transient change is skin conductance associated with a discrete experience
cardiovascular activity - heart rate
electrocardiogram (EKG) - recording electrical signals associated with heart beats
cardiovascular activity - blood pressure
systoles, and a measurement of the minimum pressure during the periods of relaxation, the diastoles
> hypertension: chronically high blood pressure