The Effects of Early Social Relationships on Neurotransmitter Development and the Vulnerability to Affective Disorders.

Recent evidence has shown that early exposure to stressful stimuli in the environment can impact the monoaminergic neurotransmitter systems, the structural development of the brain, and alter gene expression. In this article, we review data from animal studies, nonhuman primate studies, and human studies, which illustrate that environmental factors can influence brain chemistry and behavior. One important early social interaction is the mother-infant dyad.

Characteristics of adolescent girls with depressive symptoms in a so-called "normal' sample.

Objective: Forty-four percent of adolescent girls who had been screened for absence of psychiatric disorder reported depressive symptoms on a structured interview. Girls reporting symptoms were assigned to a depression group and compared to those who were free of depressive symptoms on behavioral and neuropsychological measures to determine if there were meaningful differences in cognition, behavior and motivation/self-perception between groups.

Method: Adolescent girls were randomly selected from local schools to participate in a study of neuropsychological development in adolescence.

Influence of depression on cognitive functioning in Fragile X females.

We sought to determine the frequency of a history of major depression in women with Fragile X syndrome. In addition, we attempted to disentangle the cognitive effects of major depression from those of Fragile X syndrome. Thirty-seven mothers of developmentally delayed children (Fragile X syndrome: n = 18; comparison group n = 19), matched for age, educational level, and socioeconomic status, were administered psychiatric and neuropsychological measures.

Neurobehavioral characteristics of CGG amplification status in fragile X females.

Neurobehavioral correlates of CGG amplification were studied in 17 nonretarded adult female carriers of fragile X syndrome. The results revealed a significant relationship between IQ and the number of CGG repeats in the 5' untranslated region of the FMR1 gene. Women with a full mutation (> 200 CGG repeats) scored below average in IQ, visual-spatial perception, visual-spatial organization, and executive function.

Urinary catecholamines in attention-deficit hyperactivity disorder with and without comorbid anxiety.

Objective: To determine whether there are differences in noradrenergic or adrenergic functioning in children with attention-deficit hyperactivity disorder (ADHD) with and without anxiety.

Method: ADHD children with and without a comorbid overanxious (ANX) disorder were compared to each other and to normal controls in terms of 2-hour urinary excretion of norepinephrine (NE), epinephrine (EPI), and their metabolites. All subjects performed a fixed series of mentally stressful tasks during the collection period.

Classical conditioning in children with attention deficit hyperactivity disorder (ADHD) and anxiety disorders: a test of Quay's model.

Quay (1988) put forward a model of childhood mental disorders based on Gray's (1982) theory that there exists within the brain a behavioral inhibition system (BIS), which processes signals related to aversive or punishing stimuli. According to this model, children with attention deficit hyperactivity disorder (ADHD) show lower than optimal levels of activity in this system, which leads to less responsiveness at a physiological level to signals related to punishment. Children with ADHD and controls were compared on a classical conditioning paradigm.

Neurochemistry and child and adolescent psychiatry.

This article reviews some of the neurochemistry and neurophysiology of three neurotransmitters: dopamine, norepinephrine, and serotonin. These neurotransmitters are selected because they appear to be involved in the regulation of several important behavioral systems that help regulate the interaction of the organism with its external environment, because many of the psychotropic drugs' modes of action may be result from their effects on these neurotransmitter systems, and because the majority of neurochemical studies in child psychiatry have focused on these three neurotransmitters. After the review of the neurotransmitter systems, neurochemical studies in several child psychiatric disorders are reviewed to illustrate possible biochemical/behavioral relationships in child psychiatry.

Differences in heart rate and blood pressure in children with conduct disorder, major depression, and separation anxiety.

Heart rate and blood pressure of children and adolescents admitted to a psychiatric hospital were compared among those diagnosed conduct disorder, major depressive disorder, and separation anxiety disorder. Subjects with conduct disorder had a lower heart rate compared to subjects without a conduct disorder diagnosis; and subjects with separation anxiety disorder had higher heart rate and systolic blood pressure compared to subjects without an anxiety disorder diagnosis. Subjects with major depressive disorder had higher systolic blood pressure than subjects with conduct disorder but no difference in heart rate.

Catecholamines and diagnoses in children.

Theoretically, noradrenergic (NA) function may be lower in subjects with undersocialized conduct disorder (CDU) and higher in subjects with anxiety/depressive disorder. To test this hypothesis, diagnostic and 24-hour urine catecholamine measures were compared between subjects with plasma dopamine-beta-hydroxylase (D beta H) activities less than 6 mumoles/min/L (low D beta H group) and greater than 15 mumoles/min/L (high D beta H group). Several measures relating to norepinephrine metabolism were lower in the low D beta H group, and the low D beta H group had more diagnoses of CDU and fewer anxiety and depressive disorder diagnoses.

Attention deficit disorder symptoms and urine catecholamines.

The symptoms of hyperactivity, impulsivity, and concentration deficits associated with attention deficit disorder (ADD) may be related, in part, to alterations in dopaminergic and noradrenergic functioning. In this study we correlate the above symptoms with 24-hour urinary catecholamines and their metabolites in emotionally disturbed boys divided into two groups based on their plasma dopamine-beta-hydroxylase (DBH) activities and also divided into the following diagnostic groups: conduct disorder, undersocialized; conduct disorder, socialized; and subjects without conduct disorder. Boys in the low DBH group showed significant correlations between the ADD symptoms and the biochemical measures.

Plasma dopamine-beta-hydroxylase and preschool behavior in children with conduct disorder.

The preschool behavior history and a history of abuse or neglect were compared between emotionally disturbed boys with and without conduct disorder (CD), and between boys with high and low plasma dopamine-beta-hydroxylase (D beta H) activities and CD. Boys with CD had the expected increase in preschool behaviors associated with attention deficit disorder (ADD) and CD as well as more reports of abuse or neglect. A higher percentage of boys with low D beta H were reported to have preschool behaviors associated with ADD.

DBH, MHPG, and MAO in children with depressive, anxiety, and conduct disorders: relationship to diagnosis and symptom ratings.

Plasma 3-methoxy-4-hydroxyphenylglycol (MHPG), plasma dopamine-beta-hydroxylase (DBH) activity, and platelet monoamine oxidase (MAO) were obtained in 42 boys (7-14 years old) consecutively evaluated at a community mental health clinic. The boys were diagnosed according to DSM-III criteria by a child psychiatrist using a semistructured interview with the parent and child. The Revised Behavior Problem Checklist (RBPC) and the Revised Children's Manifest Anxiety Scale (RCMAS) were consecutively obtained on the last 24 subjects.

Comparison of whole blood serotonin and platelet MAO in children with schizophrenia and major depressive disorder.

Whole blood serotonin and platelet monoamine oxidase (MAO) activity in boys with schizophrenia, schizotypal personality disorder, or major depressive disorder was compared with that of boys serving as controls. Boys with schizophrenia and schizotypal personality disorder had significantly higher platelet MAO than boys with major depressive disorder or controls. Boys with major depressive disorder had lower whole blood serotonin than boys with schizophrenia or schizotypal personality disorder.

Therapeutic response of a schizophrenic boy to a methylphenidate-chlorpromazine combination.

Methylphenidate in combination with chlorpromazine proved effective in the treatment of a boy with schizophrenia. Neuroleptics alone had not caused sufficient improvement to maintain him outside the hospital.

Biochemical differences in children with conduct disorder socialized and undersocialized.

The authors compared plasma dopamine beta-hydroxylase (DBH), platelet monoamine oxidase (MAO), whole blood serotonin, and RBC catechol O-methyltransferase (COMT) in 25 children with conduct disorder and 20 control children. They found that children diagnosed as having conduct disorder undersocialized had significantly lower DBH activity than children diagnosed as having conduct disorder socialized and the control group. The children with conduct disorder socialized had significantly higher COMT activity than the other two groups.