Child Psychopathology - Neurology and Etiology

Neurology and Etiology

Borderline personality disorder (BPD) is one of many psychopathology disorders a child can suffer from. In the neurobiological scheme, borderline personality disorder may have effects on the left amygdala. In a 2003 study of BPD patients versus control patients, when faced with expressions that were happy, sad, or fearful BPD patients showed significantly more activation versus control patients. In neutral faces, BPD patients attributed negative qualities to these faces. As stated by Gabbard, an experimenter in this study: ""A hyperactive amygdala may be involved in the predisposition to be hyper vigilant and over reactive to relatively benign emotional expressions. Misreading neutral faces is clearly related to transference mis-readings that occur in psychotherapy and the creation of bad object experiences linked with projective identification.""

Also linked to BPD, is the presence of serotonin transporter (5-HTT) in a short allele demonstrated larger amygdala neuronal activity when presented with fearful stimuli as in comparison to individuals with a long allele of 5-HTT. As found in the Dunedin longitudinal study a short allele of 5-HTT predisposes the person to have hyperactivity in the amygdala in response to trauma, and thus moderated the impact of stressful life events leading to a higher risk of depression and suicidal idealities. These same qualities were not observed in individuals with long alleles of 5-HTT. However, the environment the child is in can change in impact of this gene, proving that correct treatment, intensive social support, and a healthy and nurturing environment can modify genetic vulnerability.

Possibly the most studied or documented of the child psychopathologies is Attention Deficient Hyperactivity Disorder (ADHD) which is marked with learning disabilities, mood disorders, and/or aggression. Though believed to be over diagnosed, ADHD is highly comorbid for other disorders such as depression and obsessive compulsive disorder. In studies of the prefrontal cortex in ADHD children, which is responsible for the regulation of behavior, cognition, and attention; and in the dopamine system there has been identified a hidden genetic polymorphisms. More specific, the 7-repeat allele of the dopamine D4 receptor gene, responsible for inhibited prefrontal cortex cognition and less efficient receptors, causes more externalized behaviors such as aggression since the child has trouble “thinking through” seemingly ordinary and at level childhood tasks.