In this article, Meston and FrohlichArticle provide a review of the literature on the neurobiology of sexual function. The influence of endocrine (androgens, estrogens, progesterone, prolactin, oxytocin, cortisol, pheromones), neurotransmitter and neuropeptides (nitric oxide, serotonin, dopamine, epinephrine, norepinephrine, opiods, acetylcholine, histamine, GABA), and central nervous system (brainstem, hypothalamus, forebrain) influences on male and female sexual function are discussed in terms of sexual desire, arousal, and orgasm/ejaculation stages of sexual response. The focus of the review is on human research with some reference to the animal literature.
Auditory hallucinations or "voices" are a cardinal feature of schizophrenia. Functional neuroimaging provides a powerful means of measuring brain activity during auditory hallucinations. Using a novel functional magnetic resonance method, Shergill et alArticle found that auditory hallucinations were associated with activation in a network of cortical areas that are normally involved in producing and perceiving language. This is consistent with the notion that auditory hallucinations arise through the disruption of normal cognitive processes, such as the monitoring of one's own verbal thoughts.
Postpartum depression is a serious mental health problem that causes women great suffering and can have negative consequences for their marriages and the social and emotional development of their infants. O'Hara et alArticle compared 12 sessions of interpersonal psychotherapy (IPT) with a waiting list control (WLC) group and found that IPT resulted in significant improvements in depressive symptoms and social adjustment relative to the WLC group for postpartum depressed women. Interpersonal psychotherapy represents a good alternative to pharmacotherapy, particularly for breastfeeding women, and should be more widely disseminated to clinicians.
Stein et alArticle report findings from a community survey confirming the high prevalence (approximately 7%) of social phobia (also known as social anxiety disorder) in the community. Respondents were asked to rate how social fears and/or avoidance had affected their functioning in specific areas (eg, school functioning) and to state whether they had made particular accommodations to their lives as a result (eg, dropping out of school to avoid being the center of attention). The findings show that social anxiety and avoidance have a remarkably negative impact on the functioning of a large sector of the population.
Identifying strong, specific childhood risk factors for the development of adult schizophrenia has proved difficult. Poulton et alArticle present the first direct evidence for continuity of self-reported psychotic symptoms from childhood to adulthood. In their 15-year longitudinal study, children reporting psychotic symptoms at age 11 years were 16 times more likely than symptom-free children to develop schizophreniform disorder by age 26 years. This elevated risk applied specifically to schizophreniform disorder, not other psychiatric disorders, and did not simply result from high levels of general psychopathology in childhood.
In mammalian prefrontal cortex (PFC), reelin, released from layers I-II GABAergic interneurons, adheres to integrin receptors located on dendritic spines of pyramidal neurons. Guidotti et alArticle report on a correlation between reelin and glutamic-acid-decarboxylase (GAD67) in the PFC of nonpsychiatric subjects. When reelin and GAD67 levels are decreased by 30% to 50% in patients with schizophrenia, this correlation is disrupted. A similar decrease and lack of correlation is observed in bipolar disorder with psychosis, but not in unipolar depression. The down-regulation of GAD67 and reelin expression may help to explain the decrease of dendritic spine density reported to exist in neocortex of patients with schizophrenia.
Vascular brain lesions, including cerebral white matter lesions, are increasingly recognized as an etiologic factor of depression in elderly persons. In one of the largest population-based studies in an elderly population to date, de Groot et alArticle report that the severity of (mainly subcortical) white matter lesions is associated with the presence of depressive symptoms as well as with a history of late-onset depression. No relation was found between white matter lesions and a history of early-onset depression.
Autism is a complex genetic syndrome likely to result from distinct neurobiological processes. To address this complexity, Maziade et alArticle looked for a prolongation of early brainstem auditory evoked response (BAER) in autistic probands and members of their families. First, they found a significant prolongation of BAER in autistic probands and then observed a similar prolongation in the unaffected relatives of these probands, as compared with a large sample of normal controls. These findings provide powerful leads for detecting the pathophysiological effects underlying the heterogeneity of autism and for identifying the defective genes involved in the causes of autism.