personality disorders

Question 1

genetic influences on PDs

Answer 1

Heritability estimates (Torgenson et al., 2000)

Cluster A= 0.37
Cluster B= 0.60
Cluster C= 0.62

• Torgersen et al., calculated heritability estimates for all personality disorders, with many estimates being substantial. Showing personality disorders have a high genetic component. However, its important to note the small sample size in this study.
• Coolige et al., found a estimation of 0.75

Question 2

environmental causes to PDs

Answer 2

• childhood physical, emotional, and sexual abuse is associated with all PDs (Rettew et al., 2003) - 61% experienced a form of abuse
• low levels of parental affection or nurturing were associated with a higher risk of antisocial PD (Johnson et al., 2006)
• higher levels of abuse, neglect, instability in environment, and paternal psychopathology associated with borderline PD (Helgeland & Torgersen, 2004)

Question 3

link between personality and PDs

Answer 3

• Link between personality and personality disorders
• Widiger (2009)
• personality disorders as profiles of the five-factor model
• personality disorders involve constellations of adaptive and maladaptive personality traits

Question 4

should PDs be a discrete disorder

Answer 4

 A long-standing problem with PDs is the comorbidity among PDs & with other mental disorders
 Are PDs really discrete in nature?
 Are PDs really distinct from other mental disorders?
 – Cluster A PDs could be seen as a mild and persistent form of psychotic disorders
 – Cluster C PDs and anxiety disorders overlap considerably rather than being distinct

• Comorbidity= accounting for the presence of one or more pd, in addition to a primary pd, and in the existence of additional clinical conditions alonggisde the initially diagnosed pd
• Comorbidity rates are high among pd, meaning there is huge overlpas between pds. For example Critchfield et al., showed borderline pd was linked to all clusters A, B, and C as it had features overlapping in all these areas.

Question 5

biological and neuropsychological factors to PDs

Answer 5

• Its suggested NTs andPDs are associayted in 4 aspects of psychological functioning and behaviorur;
• cognitive/perceptual- brain systems related to attention and response. The important NT is dopamine. Important in understanding cluster A as high levels of dopamine= excitement, energy, suspiciousness, paranoia, tendency to misinterpret the environment
• Impulsivity/aggression- brain systems related with the capacity to inhibit behaviour. The important Nt is serotonin. Linked to cluster B- decreased seretoning= uninhibited in their behaviours,
• Affect regulation- this means emotional states. Brain systems related to stability ofmood. NT= noradrenergic-cholinergic (stress hormone). Linked to cluster B, specifically borderline PD
• Anxiety/inhibition- brain systems linked to pleasure aspects of the brain. Nt= seretoning, and dopamine. Reduced dopamine and increased serotonin related to cluster C