1. Briana Cassetta Kiehl, K. A., et al (2001). Limbic abnormalities in affective processing by criminal psychopaths as revealed by functional magnetic resonance imaging. Bio Psychiatry, 50, 677-684.

2. Background  Psychopathy Personality disorder 1% of general population, 15-25% of incarcerated offenders Characterized by: ○ Superficiality ○ Persuasiveness ○ Lack of empathy ○ Lack of guilt, remorse

3. Introduction  Prior research using behavioural methods Criminal psychopaths fail to experience emotional significance of stimuli Fail to show normal differentiated responses between emotional and neutral words Require more cognitive resources to process and evaluate affective stimuli

4. Introduction  Purpose: Use whole brain fMRI to examine neural systems of emotional processing during an affective memory task  Hypothesis: Psychopaths will show less activation than healthy controls and criminal nonpsychopaths when processing affective words compared with neutrals

5. Methods  Subjects: 8 criminal psychopaths and 8 criminal nonpsychopaths from prison in Abbotsford ○ Escorted to UBC Hospital’s MRI Unit ○ Hare Psychopathy Checklist-Revised 8 healthy controls from general population

6. Methods  Materials and Procedure: 8 trials with 3 sequential phases: ○ Encoding: memorize list of 12 words ○ Rehearsal: mentally rehearse words ○ Recognition: 6 correct words and 6 incorrect words (indicate yes or no)

7. Methods  Procedure: 25s rest between trials Half of trials neutral words, half negative Words similar in length, imagery, concreteness 2 practice runs prior fMRI done during task

8. Results  No differences: neutral vs. rest  Less affect-related activity in: Amygdala/hippocampal formation Parahippocampal gyrus Ventral striatum Anterior and postior cingulate gyri  Greater activation for affective stimuli in: Bilateral fronto-temporal cortex

9. Results

10. Discussion  Support hypothesis: abnormalities in limbic system and frontal cortex  Amygdala, ventral striatum, hippocampal formation: emotion and memory  Inferior lateral frontal cortex: semantic and decision-making processes

11. Discussion  Strengths: fMRI to identify specific structures No group differences  Limitations: Small sample size for groups (sample specific effects?) Substance abuse Other disorders in criminal psychopaths

12. Discussion  Future studies: Different affective stimuli ○ Faces ○ Pictures Identification of other possible disorders ○ Depression / Mood Bigger sample size