Chapter 5

Professor P., a biopsychologist, experienced tests similar to his work before brain surgery to remove a tumor on the right auditory-vestibular cranial nerve.
Auditory abilities assessed through sound detection tests and EEG signal measurement in auditory cortex.
Vestibular function tested by injecting cold water into his ear, revealing significant deficits in hearing and balance.
EEG responses documented to establish baseline for surgery to avoid facial nerve damage (cranial nerve VII).
Case illustrates the overlap of research methods in biopsychology and clinical settings.

Overview of diverse techniques used by biopsychologists, focusing on methods for visualizing and stimulating the living human brain.

Conventional X-Ray: Ineffective for brain imaging; relies on differential absorption of x-rays but brain structures absorb similarly.
Contrast X-Rays: Use injected substances to heighten contrast (Cerebral Angiography - visualizes cerebral circulation).
Computed Tomography (CT): Computer-assisted x-ray that creates 3D representations of brain layers, enabling better visualization.

Positron Emission Tomography (PET): Assesses brain activity by documenting distribution of radioactively labeled ligands injected into patients.
Magnetic Resonance Imaging (MRI): High-resolution images via radio-frequency waves measurement; benefits include higher clarity than CT.
Diffusion Tensor MRI: Identifies pathways of rapid water diffusion, revealing major axonal tracts (connectomes).
Functional MRI (fMRI): Offers functional images based on increased blood oxygen levels in active brain areas; utilizes BOLD signal.

Functional Ultrasound Imaging (fUS): Examines blood volume increases in active brain regions, advantages include portability and non-invasive nature.

Various methods to stimulate or inhibit specific brain areas to assess their role in cognition and behavior.

Transcranial Magnetic Stimulation (TMS): Temporarily disables brain areas to study effects on cognition/behavior.
Transcranial Electrical Stimulation (tES): Applies current through scalp electrodes to enhance neuronal activity.
Transcranial Ultrasound Stimulation (tUS): Can stimulate cortical and subcortical structures, also used for permanent lesioning.

Techniques to record physiological activity from the human body, including EEG, muscle tension, eye movement, skin conductance, and cardiovascular activity.

Scalp EEG: Measures overall brain electrical activity via electrodes; useful for identifying states of consciousness and pathologies.
Magnetoencephalography (MEG): Records changes in magnetic fields associated with neural activity; offers better spatial resolution than EEG.

Muscle Tension (EMG): Used to assess arousal and psychological states via tension measures in skeletal muscles.
Eye Movement (EOG): Tracks eye movement patterns to interpret visual attention and cognitive processes.

Skin Conductance: Measures changes in electrical conductivity related to emotional arousal (SCL and SCR).
Cardiovascular Activity: Assesses heart rate and blood pressure as indicators of emotional states.

Techniques focusing on direct investigation of brain function in nonhuman animals.

Aspiration Lesions: Removal of cortical tissue using suction; effective with minimal damage to surrounding areas.
Radio-Frequency Lesions: Destroys tissue with heated current through stereo-axially placed electrodes.
Reversible Lesions: Temporary disruption of activity in target brain areas for testing purposes.

Administration of drugs to manipulate neurotransmitter effects and observe behavioral outcomes.

Includes oral, intragastric, hypodermic methods, and localized delivery via stereotactically implanted cannulas.

Use of selective neurotoxins for more precise lesioning of specific neuronal types while preserving others.

Modern approaches in biopsychology utilizing genetic techniques, including gene knockout and editing to study gene-behavior relationships.

CRISPR-Cas9: Allows targeted alterations of specific genes, offering innovative research avenues in biopsychology.

Use of engineered light-sensitive ion channels (opsins) for precise control of neuron activity using light, providing insights into brain functioning.

Investigating behavior through specific paradigms designed to measure responses to stimuli and environmental changes.

Evolution of neuropsychological testing from single-test to customized test-battery approaches aimed at accurately diagnosing and characterizing brain damage.
Common tests include WAIS and various memory and language assessments.

Integrates methods of visualization, stimulation, and recording into a comprehensive overview of biopsychological research, emphasizing the importance of using multiple techniques to derive accurate scientific conclusions.