The Research Methods of Biospychoagy Flashcards
• is a method of studying
organs using X-rays and the
administration of a special
dye, called a contrast medium.
• This test allows the
radiologist to
evaluate structures that are
not clearly evident on
conventional X-ray exams.
CONTRAST XRAYS
• is a diagnostic test that uses an X-ray.
• Uses the infusion of a radio-opaque dye into a
cerebral artery to visualize the cerebral
circulatory system during x-ray photography
• It produces a cerebral angiogram, or an image
that find blockages or other abnormalities in the
blood vessels of your head and neck.
CEREBRAL ANGIOGRAPHY
• Also known as CT scan
• Is a computer-assisted X-ray
procedure that can be used
to visualize the cranium and
the internal structures of
the living body
X-RAY COMPUTED TOMOGRAPHY
• scanners use strong magnetic fields, magnetic field gradients, and
radio waves to generate images of the organs in the body.
• A 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.
• provides clearer images of the brain than does CT.
MAGNETIC RESONANCE IMAGING
• Was the first brain-imaging technique to provide images of
brain activity (functional brain images) rather than images of
brain structure (structural brain images).
• The scan uses a special dye containing radioactive tracers.
These tracers are either swallowed, inhaled, or injected into a
vein depending on what part of the body is being examined.
POSITRON EMISSION TOMOGRAPHY
• measures brain activity by detecting changes
associated with blood flow.
• Produce images representing the increase in
oxygen flow in the blood to active areas of the
brain.
• BOLD Signal (Blood-oxygen-level-dependent
signal)– the signal recorded by fMRI
FUNCTIONAL MRI
FOUR ADVANTAGES OF FMRI OVER PET
1.Nothing has to be injected into the subject
2.It provides both structural and functional information in the
same image
3.Its spatial resolution is better
4.It can be used to produce three-dimensional images of
activity over the entire brain
• is a functional neuroimaging technique for mapping brain activity
by recording magnetic fields produced by electrical currents
occurring naturally in the brain, using very sensitive magnetometers.
Its major advantage over fMRI is its temporal resolution; it can record fast changes in neural activity
MAGNETOENCEPHALOGRAPHY
• Is a technique for affecting the activity in an area of the cortex by creating a magnetic field under a coil positioned next to the skull.
• In effect, the magnetic stimulation temporarily turns off part of the brain while the effects of the disruption on cognition and behavior are assessed.
TRANSCRANIAL MAGNETIC STIMULATION
• Is a measure of the gross electrical
activity of the brain.
• It is recorded through large electrodes
by a device called an
electroencepalograph.
• The scalp EEG signal reflects the sum of
electrical events throughout the head.
SCALP ELECTROENCEPHALOGRAPHY
(EEG)
• Also called Berger’s wave after the
founder of EEG.
• One type of brain waves in the frequency
range of 7.5–12.5 Hertz arising from
synchronous and coherent (in phase or
constructive) electrical activity
of thalamic pacemaker cells in humans.
ALPHA WAVES
• Measure of somatic nervous system activity.
• is the usual procedure for measuring muscle tension.
ELECTROMYOGRAPHY
(EMG)
• Measure of somatic
nervous system activity.
• The electrophysiological
technique for recording
eye-movements
ELECTROOCULOGRAPHY (EOG)
• measure of autonomic nervous
system activity
• Skin Conductance Level
(SCL)
• Skin Conductance Response
SKIN
CONDUCTANCE
is a measure of the
background level of skin
conductance that is associated
Skin Conductance Level
(SCL)
is a measure of the transient
changes in skin conductance that
are associated with discrete
experiences.
Skin Conductance Response
• Heart Rate
•Blood Pressure
•Blood Volume
CARDIOVASCULAR ACTIVITY
• the electrical signal that is associated with each
heartbeat can be recorded through electrodes placed
on the chest.
• Electrocardiography (ECG)
HEART RATE
is the process of
recording the electrical activity of the heart over a
period of time using electrodes placed over the skin
Electrocardiography (ECG)
• Systoles
• Diastoles
• Sphygmomanometer
BLOOD PRESSURE
• refers to the various techniques for
measuring changes in the volume of
blood in a particular part of the
body
BLOOD VOLUME
Plethysmography
• The first step in many biopsychological experiments
• Means by which experimental devices are precisely positioned in the depths of the brain
• Uses the following:
• Stereotaxic atlas, used to locate brain structures from a designated reference point
• Stereotaxic instrument, used to insert the experimental device to the subject’s brain
STEREOTAXIC SURGERY
• Usually employed in biopsychological studies of laboratory animals
• Falls into one of three categories:
• LESION METHODS
• ELECTRICAL STIMULATION METHODS
• INVASIVE RECORDING METHODS
INVASIVE PHYSIOLOGICAL
RESEARCH METHODS
• Method wherein a part of the body is removed,
damaged, or destroyed to determine the
functions of the lesioned structures
• Types of lesions:
• ASPIRATION LESIONS
• RADIO-FREQUENCY LESIONS
• KNIFE CUTS
• CRYOGENIC BLOCKADE
LESION METHOD
is the method of choice for areas of cortical tissue that is
accessible to the eyes and instruments of the surgeon
• Tissue samples are drawn off by suction through a fine-tipped handheld glass pipette
Aspiration lesions
make use of high-frequency current through the target tissue using a
stereotaxically positioned electrode
• The radiofrequency current generates heat, which destroys the
cortical tissue
Radio-frequency lesions
is
used to eliminate conduction in
a nerve or tract
• A device is stereotaxically
positioned in the brain, and the
blade swings out to make the
cut
Knife cuts or sectioning
makes
use of a coolant which is
pumped through an implanted
cryoprobe
• They produce reversible
lesions by temporarily stopping
neural activity by cooling brain
structures
Cryogenic blockade
INTERPRETING LESION EFFECTS
• Lesion effects are difficult to interpret
• Difficult to completely destroy a structure without
producing significant damage to adjacent structures
• Electrical stimulation of neural structures
help identify their functions
• Stimulation is delivered across the two
tips of a bipolar electrode
• Effects are usually opposite of those seen
with lesions located at the same site
ELECTRICAL STIMULATION2
METHOD THREE: INVASIVE
ELECTROPHYSIOLOGICAL RECORDING METHODS
• Invasive electrophysiological recording methods include the following:
• EXTRACELLULAR UNIT RECORDING
• INTRACELLULAR UNIT RECORDING
• MULTIPLE-UNIT RECORDING
• INVASIVE EEG RECORDING
provides a record of the firing of a
neuron but has no information on it’s
membrane potential
• are recordings of electrical potentials
produced by a cell, either in extracellular
fluid near the cell of interest, or noninvasively
Extracellular Unit Recording
is the measurement of voltage or current across the membrane of a cell. It typically involves an electrode inserted in the cell and a
reference electrode outside the cell.
• Usually performed on chemically immobilized animals
INTRACELLULAR UNIT RECORDING
makes use of
larger electrode tips, hence, it picks up
signals from many neurons
• Records the total number of action
potentials in a given unit of time (e.g. per
0.1 second)
MULTIPLE-UNIT RECORDING