Is depression an adaptation, a pathological extreme of a defense, or an abnormal state unrelated to any adaptation? NesseArticle suggests that in unpropitious situations, low mood can be useful to prevent losses and reallocate effort. It may escalate to depression if an individual is unable to give up an unreachable goal. Global reductions in initiative and self-esteem may prevent prematurely abandoning an unsatisfactory but irreplaceable major life enterprise. This could explain why depression is prevalent in people who are trapped in failing relationships or other major life enterprises, and why depression often maintains itself in a vicious cycle.
It is not until midadolescence that a dramatic shift in depression rates marks the onset of the 2:1 female-to-male gender gap in unipolar depression. Cyranowski et alArticle offer a theoretical framework that may explain the timing of this phenomenon.
Birmaher et alArticle report on a 2-year follow-up of adolescents who participated in a randomized clinical psychotherapy trial for depression. Despite greater efficacy of cognitive therapy over family or supportive therapy for the acute treatment of depression, the rates of recovery (80%), recurrence (30%), and chronic depressive course (20%), were similar across the 3 treatments.
Many children go through a period of aggressive behavior that is serious enough to warrant a diagnosis of conduct disorder, but later adjust normally. Others persist in aggressive behavior for years and develop chronically antisocial lifestyles as adults. McBurnett et alArticle studied boys with problem behavior for 4 years and collected samples of their saliva at 2 time points. Low salivary cortisol levels at both time points were associated with early onset and persistence of aggression. Although the study could not determine causality, it suggests that one of the biological systems that responds to stress is altered in some children with persistent aggression.
Bartzokis et alArticle measured the amount of iron in brains of patients with Alzheimer disease (AD) and control subjects, using a novel noninvasive magnetic resonance imaging method that measures the iron stored in ferritin molecules. Patients with AD had higher iron levels in the basal ganglia than control subjects. Iron levels did not differ between the groups in frontal lobe white matter. Although the study cannot establish a direct causal relationship between increased iron levels and AD, iron is a known catalyst of damaging free radical reactions. Future research may elucidate the role of brain iron as a risk factor for AD.
Deficits in attention and cognition are common in individuals with schizophrenia, possibly due to an inability to filter out irrelevant sensory stimulation, leading to information overload. A brain response reflecting the ability to inhibit repeated stimulation, collected using the auditory dual-click P50 paradigm, has served as a measure of this filtering deficit in schizophrenia. Patterson et alArticle used a computerized procedure to evaluate temporal variability, and observed that fluctuations in the timing of the P50 brain response from trial-to-trial influence the extent of inhibition observed. Temporal variability may be a central feature underlying problems in attention and cognition in schizophrenia.
Alterations in the synaptic circuitry of the prefrontal cortex (PFC) are thought to contribute to cognitive dysfunction in schizophrenia. Glantz and LewisArticle found that the density of dendritic spines, markers of excitatory synapses, was selectively decreased on deep layer 3 pyramidal neurons in the PFC of schizophrenic subjects. In contrast, spine density did not significantly differ among normal controls, schizophrenic subjects, and psychiatric comparison subjects for other pyramidal neurons in the PFC or in primary visual cortex. These finding suggest that excitatory inputs to layer 3 of the PFC, which may include projections from the thalamus, are reduced in schizophrenia.
A commentary by SelemonArticle is included.
Hoehn-Saric et alArticle found that the seratonin reuptake inhibitor sertaline had greater efficacy than desipramine (primarily a norepinephrine reuptake inhibitor) on measures of depression and symptoms for patients with obsessive-compulsive disorder and concurrent major depressive disorder.
Perspectives on the direction of psychiatric research in the new millenium by Frank and KupferArticle, Akil and WatsonArticle, HymanArticle, and Coyle and SchwarczArticle are included.