Personality psychology is a branch of psychology which studies personality and individual different processes - that which makes us into a person. One emphasis is on trying to create a coherent picture of a person and all his or her major psychological processes. Another emphasis views it as the study of individual differences. These two views work together in practice. Personality psychologists are interested in a broad view of the individual. This often leads to an interest in the most salient individual differences among people.
In psychology, personality is a collection of emotional, thought and behavioral patterns unique to a person that is consistent over time. The word originates from the Latin persona, which means "mask." Significantly, in the theatre of the ancient Latin-speaking world, the mask was not used as a plot device to disguise the identity of a character, but rather was a convention employed to represent, or typify that character.
There are several theoretical perspectives on personality in psychology, which involve different ideas about the relationship between personality and other psychological constructs, as well as different theories about the way personality develops. Most theories can be grouped into one of the following classes.
Generally the opponents to personality theories claim that personality is "plastic" in time, places, moods and situations. Changing personality may in fact resulting from diet (or lack of), medical effects, historical or subsequent events, or learning. Stage managers (of many types) are especially skilled in changing a person's resulting "personality". Most personality theories will not cover such flexible nor unusual people situations.
Types of personality tests include the Holland Codes, the Rorschach test, the Minnesota Multiphasic Personality Inventory, the Myers-Briggs Type Indicator, NEO PI-R, and the Thematic Apperception Test. Critics have pointed to the Forer effect to suggest that some of these appear to be more accurate and discriminating than they really are.
Personality psychology is often closely associated with social psychology.
Around the 1990s, neuroscience entered the domain of personality psychology. Whereas previous efforts for identifying personality differences relied upon simple, direct, human observation, neuroscience introduced powerful brain analysis tools like Electroencephalography(EEG), Positron Emission Tomography(PET), and Functional Magnetic Resonance Imaging(fMRI) to this study. One of the founders of this area of brain research is Richard Davidson of the University of Wisconsin-Madison. Mr Davidson's research lab has focused on the role of the prefrontal cortec(PFC) and amygdala in manifesting human personality. In particular, this research has looked at hemispheric asymmetry of activity in these regions.