How we change what others think, feel, believe and do
Physiological psychology is the study of the physiological basis of how we think, connecting the physical operation of the brain with what we actually say and do. It is thus concerned with brain cells, brain structures and components, brain chemistry, and how all this leads to speech and action. It is also, of course, important to understand how we take in information from our five senses.
Modern psychology grew out of medical explorations of the brain and one of the first psychology textbooks was called 'Principles of Physiological Psychology'.
In addition to the common principle of generalization, physiologists make significant use of the principle of reduction, seeking the simplest explanation for complex phenomena (perhaps in contrast with a more detailed description that a physicist may use).
Much early knowledge was gained through observing how behavior changes when different parts of the brain are damaged. Animal experiments, always controversial, have also been used, for example by removing or cutting various parts of the brain and observing differences in behavior.
Utilizing necessary brain surgery has also been useful, including prodding parts of the brain and asking the conscious patient what they experience (there are no nerve endings in the brain so the patient feels no pain).
Study of brain chemistry have included the exploration of how various drugs affect brain functioning.
Modern scanning systems, such as fMRI and PET have given further insights as activation of parts of the brain can be seen without the more intrusive former methods.
Physiological psychology covers the general area of 'brain and behavior' that is a modular subject in many university courses.
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