Biopsychology Research Methods

Research Methods of Biopsychology

• Biopsychologists seek to understand what biopsychologists do through research methods.
• This research can involve studying the nervous system, behavior, and cognitive processes.

Part One: Methods of Studying the Nervous System

• Methods of Visualizing and Stimulating the Living Human Brain
• Recording Human Psychophysiological Activity
• Invasive Physiological Research Methods
• Pharmacological Research Methods
• Genetic Engineering

Part Two: Behavioral Research Methods of Biopsychology

• Neuropsychological Testing
• Behavioral Methods of Cognitive Neuroscience
• Biopsychological Paradigms of Animal Behavior

Methods of Visualizing and Stimulation

• Contrast X-rays study organs using X-rays and a contrast medium to evaluate structures not clear on conventional X-rays.

Cerebral Angiography

• A diagnostic test that uses X-rays.
• Radiopaque dye infusion into a cerebral artery visualizes the cerebral circulatory system during X-ray photography.
• The procedure produces a cerebral angiogram, finding blockages or abnormalities in the head and neck's blood vessels.

X-Ray Computed Tomography

• Is a computer-assisted X-ray procedure known as a CT scan.
• This visualizes the cranium and internal structures of the living body.

Magnetic Resonance Imaging

• MRI scanners use strong magnetic fields, gradients, and radio waves to produce images of organs.
• High-resolution images are constructed by measuring waves emitted by hydrogen atoms when activated by radio-frequency waves in a magnetic field.
• MRI gives clearer brain images than CT scans.

Positron Emission Tomography

• Functional brain images, rather than structural ones, are captured with it.
• The scan uses a special dye.
• Radioactive tracers are either swallowed, inhaled, or injected.

Functional MRI

• Measures brain activity by detecting changes associated with blood flow .
• Images represent increased oxygen flow in the blood to active brain areas.
• BOLD Signal (Blood-oxygen-level-dependent signal) is the signal recorded by fMRI.

Four Advantages of fMRI over PET

• Nothing has to be injected into the subject
• Structural and functional information is acquired in the same image
• Spatial resolution is better
• Three-dimensional images of activity over the entire brain can be produced

Magnetoencephalography

• Functional neuroimaging technique maps brain activity.
• This involves by recording magnetic fields produced by electrical currents.
• These currents occur naturally in the brain, detected using sensitive magnetometers.
• A major advantage over fMRI is its temporal resolution and its ability to record fast changes in neural activity.

Transcranial Magnetic Stimulation

• Technique affects cortex activity.
• It is achieved by creating a magnetic field under a coil positioned next to the skull.
• Temporarily turns off part of the brain.
• The disruption's effects on cognition and behavior are then assessed.

Recording Human Psychophysiological Activity

• Methods to record human psychophysiological activity are used in biopsychological research.

Scalp Electroencephalography (EEG)

• Gross electrical brain activity is measured.
• It is recorded with an electroencephalograph that uses large electrodes.
• The scalp EEG signal reflects the sum of electrical events throughout the head.

Alpha Waves

• Also called Berger's wave after the founder of EEG.
• Brain waves in the frequency range of 7.5-12.5 Hertz arise from synchronous and coherent electrical activity.
• Thalamic pacemaker cells in humans cause this.

Electromyography

• Measurement of somatic nervous system activity via EMG signal.
• Usual procedure for measuring muscle tension.

Electrooculography (EOG)

• Measurement of somatic nervous system activity.
• The electrophysiological technique for recording eye-movements.

Skin Conductance

• Measure of autonomic nervous system activity.
• Skin Conductance Level (SCL) measures the background level of skin conductance associated with a particular situation.
• Skin Conductance Response measures transient skin conductance changes.
• These changes are associated with discrete experiences.

Cardiovascular Activity

• Includes Heart Rate, Blood Pressure, and Blood Volume.

Heart Rate

• Measurement of cardiovascular activity.
• The electrical signal associated with each heartbeat recorded via electrodes on the chest.
• Electrocardiography (ECG) records the electrical activity over a period of time using electrodes placed over the skin

Blood Pressure

• Measurement of cardiovascular activity.
• Systoles, Diastoles and Sphygmomanometers are used.
• Systoles measure peak pressure during heart contraction.
• Diastoles measure minimum pressure during relaxation.
• Sphygmomanometer measures blood pressure using sphygmos (pulse).

Blood Volume

• Plethysmography refers to techniques for measuring blood volume changes in a body part

Invasive Physiological Research Methods

• Invasive techniques require penetration of the body.
• Used for controlled animal research

Stereotaxic Surgery

• First step in many biopsychological experiments.
• Experimental devices are precisely positioned in the depths of the brain.
• This can be used to target specific areas in the brain.
• Uses a Stereotaxic atlas to locate brain structures from a designated reference point.
• Uses a Stereotaxic instrument to insert the experimental device to the subject's brain

Invasive Physiological Research Methods

• Employed for the biopsychology studies of laboratory animals.
• Can be divided into Lesion methods, Electrical simulation methods and Invasive recording methods.

Lesion Method

• A part of the body is surgically incapacitated, removed, damaged, or destroyed to determine the functions of the affected structures.
• Aspiration, radiofrequency, and cryogenic blockade lesions are the types.

Aspiration Lesions

• A method of choice for accessible cortical tissue areas through the surgeons eyes and instruments.
• Tissue samples can be drawn off by suction through handheld pipette.

Radiofrequency Lesions

• Radio-frequency lesions make heat energy that destroys cortical tissue.
• High-frequency current passes through the target using a stereotaxically positioned electrode.

Knife Cuts or Sectioning

• Used to eliminate nerve conduction.
• The surgical sectioning of a nerve tract (ie cutting) is usually done to prevent impulses reaching a particular area.
• A device is stereotaxically positioned in the brain,. The device is used to swing a blade out to make the cut.

Cryogenic Blockade

• Coolant pumped through an implanted cryoprobe coolant makes use of coolant.
• Cooling brain structures produces reversible temporary lesions.

Interpreting Lesion Effects

• Lesion effects are difficult to interpret.
• It's difficult to completely destroy given structures.
• Destroying structures without damaging adjacent structures is difficult.

Electrical Stimulation

• Neural structures can be electrically stimulated to identify their functions.
• Across the two tips of a bipolar electrode.
• Effects are usually opposite of lesion effects at the same site.

Method Three: Invasive Electrophysiological Recording Methods

• Extracellular, intracellular, multiple-unit and invasive EEG recording are types of invasive electrophysiological recording.

Pharmacological Research Methods

• Administering drugs gives information about the brain.

Types of Drug Administration

• Drug administration is varied through different injection sites and other ways.
• Fed to the subject
• Injected through a tube into the stomach (intragastrically)
• Injected hypodermically into the peritoneal cavity of the abdomen (intraperitoneally, IP)
• Large muscle injections (intramuscularly, IM)
• Fatty tissue beneath the skin (subcutaneously, SC)
• A large surface vein (intravenously, IV)

Selective Chemical Lesions

• Neurotoxins: neural poisons, are poisonous to nerve tissue (neurotoxicity).
• Examples of such chemical lesions of kainic acid , Ibotenic acid and 6-hydroxydopamine (6-OHDA)

Measuring Chemical Activity of the Brain

• Techniques can be used to measure chemical activity of the brain.
• This can be done through the 2-Deoxyglucose Technique, or Cerebral Dialysis

Technique One: 2-Deoxyglucose Technique

• Subject injected with radioactive 2-DG engages in an activity of interest.
• Autoradiography: Use of X-ray (photographic) film to detect radioactive materials.

Technique Two: Cerebral Dialysis

• Extracellular concentration of specific neurochemicals in behaving animals can be measured.

Locating Neurotransmitters and Receptors in the Brain

• Techniques available:
• Immunocytochemistry
• In Situ Hybridization

Technique One: Immunocytochemistry

• Locating neuroproteins in the brain.
• Labelling antibodies with dye or radioactive element is done.
• After labelling brain tissue slices are exposed to the labelled antibodies.

Technique Two: In Situ Hybridization

• Technique locates peptides and other proteins in the brain.

Genetic Engineering

• Procedures are used for that are genetically modifed to lack a particular gene.

Gene Knockout Techniques

• Procedures are used for creating organisms under investigation that lack a particular gene

Gene Replacement Techniques

• Replacing one gene with another is an example of gene replacement.

Green Fluorescent Protein (GFP)

• Exhibitse bright green fluorescence composed of 238 amino acid residues.
• First isolated from a species of jellyfish.

Behavioral Research Methods of Biopsychology

• Looks into how the study of the brain relates to behavior and what processes link them.

Neuropsychological Testing

• Neuropsychological testing is a set of test that helps understand function and dysfunction of the brain through different measures

Important Ways Neuropsychological Testing Can Help Brain-Damaged Patients

• Assisting in diagnosing neural disorders, particularly in cases in which brain imaging (EEG) have proved equivocal.
• Serving as a basis for counseling and caring for the patients;
• Providing a basis for objectively evaluating the effectiveness of the treatment and the seriousness of its side effects.

Modern Approach to Neuropsychological Testing

• Single-test approach
• Standardized-test-battery approach
• Customized-test-battery approach

Single-Test Approach

• Designed to detect the presence of brain damage.
• Used To identify patients with psychological problems caused by structural vs. functional changes

II. Standardized-Test Battery Approach

• Patients are identified based on battery of tests rather than single tests.

Customized-Test-Battery Approach

• It does not merely identify brain damage but to characterise the psychological deficits .
• The nature psychological deficit in each brain-damaged is important to understand.

Intelligence

• Almost always included in neuropsychological testing.
• It is a poor measure of brain damage.
• Wechsler Adult Intelligence Scale (WAIS) measure for intelligence.
• First published in February 1995 by David Wechsler.
• It's an IQ test designed to measure intelligence and cognitive ability in adults and older adolescents.

The 11 Original Subtests of the WAIS (Verbal Subtests)

• Information – subject is presented with 29 questions from culture(example: Who is the president of the Philippines?)
• Digit Span - Participants must recall a series of numbers in order. Three digits are read to the subject at I-second intervals, and the subject must repeat in same order. -Vocabulary - Participants must name 35 objects in pictures or define words presented to them example: tell me the meaning of corrupt?
• Arithmetic – subject is presented with 14 arithmetic , pencil-paper not allowed
• Comprehension – subject is asked 16 questions test general principles.
• Similarities – subject is asked to explain how the items are similiar

The 11 Original Subtests of the WAIS (Performance Subtests)

• Picture Completion – subject identify important part missing from 20 drawings.
• Picture Arrangement – subject presented with 10 sets cartoon drawings-asked to arrange it-tells sensible story Block Design -- subject presented blocks that are red on two sides, ,half is with four other half with one's opposite Object Assembly - subject assembly four simple jigsaw puzzles objects Digit Symbol - subject presented symbol matching with different digit- a series digit and correct symbol to as many digits possible -90 sec

Wisconsin Card Sorting Test

• To measure frontal lobe dysfunction.
• For ages from 6.5 to 89 years of age.
• The WCST relies upon a number of cognitive function.

Biopsychological Paradigms of Animal Behavior

• Animal models reveal links processes and biology.

Behavioral Paradigm

Single set of procedures developed in investigation of behavior-phenomenon

Three Behavioral Paradigms Used To Study the Biopsychology of Laboratory Species

• Paradigms for the assessment of species-common behaviors
• Traditional conditioning paradigms
• Semi-natural animal learning paradigms"

Paradigms for the Assessment of Species-Common Behaviors

• Are those displayed by most members of those of the same age and sex.
• Including test such ,the Open-Field Test, tests of Aggressive and Defensive Behavior, and Tests of Sexual Behavior

Open-Field Test

Subject placed -large, barren chamber- recorded activity.

Tests of Aggressive and Defensive Behavior

Can be measured-during combative-between established colony-dominant male rat--smaller intruder.

Test of Sexual Behavior

Three common measures of male rat sexual behavior: mounts required to achieve intromission, intromissions required to achieve ejaculation, interval ejaculation, and the re-initiation mounting.

Traditional Conditioning Paradigms

• Such types of learnings help reveal certain behaviors or link them in a controlled way.
• It inlcuides Pavlonian (developed Ivan Pavlov) and Operant Condition Paradigm (developed by Burhuss Frederic Skinner).
• Pavlonian involves multistep -unconditioned stimulus (UCS) -meat powder--unconditioned response (UCR) - salivation.
• Operant - rate-particular voluntary response (lever press) -reinforcement or decreased-punishment.

Semi-Natural Animal Learning Paradigms

• Include Conditioned Taste Aversion, Radial Arm Maze, Morris Water Maze, and Conditioned Defensive burying.

Conditioned Taste Aversion

Is the avoidance response, which -develops to tastes ,consumption of food whose has -followed-by illness.

Radial Arm Maze

• Measure -spatial learning and memory in rats.

Morris Water Maze

• -semi-natural paradigm --study --spatial abilities of rats.

Conditioned Defensive Burying

• Rats-aversive stimulus(e.g. shock-si blast, or noxious odor)-object-wall-chamber-littered- bedding.

Explore the research methods used in biopsychology, including nervous system studies, behavioral analysis, and cognitive processes. Learn about visualizing the brain, psychophysiological activity, and invasive techniques. Discover pharmacological research, genetic engineering, neuropsychological testing, and animal behavior paradigms.