Just My Notes

How Do Psychologists Study About the Brain?

The brain is the central focus of a neuroscientist. Being a major organ of the central nervous system, the brain is responsible for monitoring and regulating many of the information coming from our external and internal environment. Studying about the brain therefore sheds important insights about the biological foundations of behavior and mental processes.

Psychologists study the brain in different ways:



Brain Lesioning

Brain Lesioning may be natural or artificial. Artificial brain damages are induced in the laboratory by surgery, laser removal and through the use of drugs; while natural brain damages may be caused by environmental hazards that are naturally occurring or by some unusual and/or common street accidents. Basically this method provides psychologists insights into what aspects of behavior are affected by damage on certain parts of the brain, and up to what extent can the damage significantly alter behavior.

Brain Staining

Staining the brain is a technique used by psychologists to pinpoint which neurons are connected and activated by each other. Because neuronal membranes contain ion channels that open and close whenever a neuron is activated, stains like horse dish peroxidase enter these channels and paint the path neurotransmitters take to transmit information to neighboring neurons. Because neurons are generally too small to be seen by the naked eye, psychologists use high-powered microscopes to see through a neuron's activity.

Brain Electrical Recording

Electrical Recording is used to monitor the electrical activity of the brain. This is because neurons communicate with each other via electrochemical transmission. One form of brain electrical recording is through the use of an electroencephalogram wherein surface electrodes are placed on the scalp. The electrical record gathered from this technique is called an electroencephalograph (or EEG), and is used mainly to study about brain disorders, epilepsy and the nature of sleep. Another form of electrical recording is single-unit recording in which the electrical activity of a single neuron is monitored using a thin probe inserted in the brain and near a particular neuron. The electrical information is then amplified to be seen and registered on the screen.

Brain Imaging

Brain Imaging is done to enable psychologists to "see" what is happening in the brain. Computerized Tomography (CT Scan) presents a clear 3-dimensional image of the brain from the assembly of various 2-dimensional x-rays of the brain. Positron-Emission Tomography (PET Scan) presents a hazy picture of the brain based on glucose consumption of the different parts of the brain. For example, different parts of the brain "light up" in accordance with the different activities we engage in. Magnetic Resonance Imaging (MRI) shows the biochemical activities of the brain by means of magnetic field and radio waves. Among the three (3) techniques for brain imaging, MRI is the most preferred method because it provides the clearest picture of the brain, is non-invasive, and poses no risks for radiation problems.