The Functional Anatomy of Personality Trait Knowledge: An fMRI Study
Condition: Healthy
Study type: Observational

Summary: 
      This study will identify the regions of the brain that are involved in personality trait
      knowledge-that is, what a person knows about aspects of personality such as "generous,"
      "honest," and others. It will also examine brain areas relating to a person's knowledge of
      how likeable those personality traits are, being familiar with the traits, and the degree of
      associating such traits with one's self. There has not been any previous study, through
      modern imaging techniques, on the location of the brain and the concepts of personality
      traits.

      Patients ages 21 to 65 who are in good health, are right handed, and native speakers of
      English may be eligible for this study. Pregnant women are not eligible. There will be 200
      participants involved in pencil-and-paper or computer tasks. Also, there will be three
      functional magnetic resonance imaging (fMRI) experiments with 32 participants. Patients may
      participate in up to three fMRI experiments.

      Patients will be recruited through NIH's Normal Control Database. They would need to have had
      a neuroexamination conducted by an NIH doctor within the last year. Patients will be
      interviewed for any medical, neurological, or psychological condition that would make it
      difficult to read the fMRI results. Depending on the studies that patients take part in, they
      will have different questionnaires to complete. They may also perform a computerized test
      that measures word associations. These tests will take about 1 to 2 hours.

      The technique of MRI uses a strong magnetic field and radio waves to obtain images of body
      organs and tissues. During the initial MRI scan, patients will lie still on a table that will
      slide into the enclosed tunnel of the scanner. They will be in the scanner not longer than 2
      hours. During the procedure, they may be asked to lie as still as possible for up to 1 hour
      at a time. As the scanner takes pictures, patients will hear knocking or beeping sounds, and
      they will wear earplugs to reduce the noise. Patients will be able to communicate with the
      MRI staff at all times during the scan, and they may ask to be moved out of the machine at
      any time. Then the functional MRI (fMRI) scan will involve taking pictures of the brain while
      patients are performing tasks. All the tasks will be explained, and patients will have the
      chance to practice them before entering the scanner. For this activity, patients will be
      asked to make decisions about what they are seeing in the tasks presented to them. They will
      decide "yes" and "no" by pressing a left or right button. This scan will take about 1 hour.
      Afterward, patients may be asked to fill out written questionnaires or to perform reaction
      time tasks by using a computer.

      This study will not have a direct benefit for participants. However, it is hoped that
      information gained will enhance researchers' understanding about which areas of the brain are
      necessary to perform certain tasks.
    

Detailed description: 
      Objective. The purpose of the protocol is to identify the brain regions involved in
      personality trait knowledge, associated affective valence and person-trait associations. We
      propose using parametric event-related fMRI in addition to classical reaction time measures,
      to answer the question of whether a specialized neural system is involved in semantic
      processing of personality trait concepts. We will apply methods that have been used in
      previous investigations to identify category-specific semantic (meaning) systems for living
      and non-living objects.

      Study Population. Healthy, normal adult, right-handed volunteers will be studied during
      functional neuroimaging and in behavioral pre-tests.

      Design. Behavioral pre-tests (N=200 subjects) are used to obtain psycholinguistic stimulus
      parameters used in the fMRI experiments. Three parametric event-related functional MRI
      experiments (for a total of 104 subjects) using personality trait concept words as main input
      stimuli will be conducted.

      Outcome Measures. The data collected will consist of questionnaire results, behavioral
      measures of cognitive performance and corresponding fMRI images. The results gained from this
      protocol will be of value in advancing the neuroscience of person perception and social
      cognition.
    

Keywords: Social Cognition; Semantic Memory; Prefrontal Cortex; Temporal Cortex; Conceptual Self