Lack of significant changes on magnetic resonance scans before and after 2 weeks of daily left prefrontal repetitive transcranial magnetic stimulation for depression.

Repetitive transcranial magnetic stimulation (rTMS) is a new technology for exploring brain function. With this method, a small electromagnet is placed on the scalp; by activating and deactivating it, nerve cells in the underlying superficial cortex are depolarized. Several studies have found that prefrontal rTMS has potential efficacy in treating depression, and this technology, in addition to being a research tool, may soon play a role in psychiatric practice. Thus, establishing the safety of this technology is important and has been studied insufficiently. The authors performed T1-weighted three-dimensional volumetric magnetic resonance (MR) imaging on 22 depressed adults (15 active, 7 control) before and after they participated in a 2-week double-blinded, placebo-controlled trial of daily left prefrontal rTMS for the treatment of depression (a total of 16,000 stimuli). Seventeen patients also had paired T2-weighted scans. In a blinded manner, MR scans were qualitatively and quantitatively assessed for structural changes. No qualitative structural differences were observed before and after treatment. In addition, volumetric analysis of the prefrontal lobe showed no changes in the 2 weeks of the study. In conclusion, 10 days of daily prefrontal rTMS at these intensities and frequencies does not cause observable structural changes on MR scans in depressed adults.

Safety and feasibility of repetitive transcranial magnetic stimulation in the treatment of anxious depression in pregnancy: a case report.

BACKGROUND: The proper treatment of mood disorders occurring during pregnancy is a major therapeutic problem since no antidepressant medications have been established as safe for the developing fetus. Several double-blind placebo-controlled studies have explored the efficacy of repetitive transcranial magnetic stimulation (rTMS) in depression. CASE: We report the case of a 36-year-old woman in her second trimester of pregnancy, whose depression (DSM-IV) and anxiety were successfully treated with rTMS. Further studies of rTMS in depressed pregnant women appear warranted.

Repetitive transcranial magnetic stimulation: perspectives for application in the treatment of bipolar and unipolar disorders.

OBJECTIVES: Transcranial magnetic stimulation (TMS) affects the brain by non-invasively stimulating the cerebral cortex and inducing electrical currents in neurons. The powerful magnetic field acts as a vector that passes across the scalp and the skull, and then converts into an electrical energy within the brain. Originally used in neurophysiology, TMS has since been applied in a variety of neuropsychiatric conditions, including mood disorders. Imaging studies in mood-disordered patients have pointed to dysfunctional limbic and prefrontal cortex activity. TMS researchers have thus postulated that dorsolateral prefrontal cortex (DLPFC) stimulation might change brain activity both locally and in paralimbic areas through transynaptic connections, and alter mood. METHODS: We will describe the technology of TMS, its applications to date, and explore its mechanisms of action. RESULTS: Several clinical trials have demonstrated TMS effects on mood in health and disease. There is a growing consensus that TMS has antidepressant effects, although little is known about the role played by a variety of stimulation parameters such as the intensity or frequency of stimulation. One study has found an antimanic effect of right prefrontal TMS. CONCLUSION: TMS is relatively safe; however, much more research is needed before TMS can be integrated into routine clinical practice.

Modeling the prehistoric Maori population.

Skeletal and comparative evidence of mortality is combined with fertility estimates for the precontact Maori population of New Zealand to determine the implied rate of precontact population growth. This rate is found to be too low to populate New Zealand within the time constraints of its prehistoric sequence, the probable founding population size, and the probable population size at contact. Rates of growth necessary to populate New Zealand within the accepted time span are calculated. The differences between this minimum necessary rate and the skeletally derived rate are too large to result solely from inadequacies in the primary data. Four alternative explanations of this conundrum are proposed: 1) skeletal evidence of precontact mortality is highly inaccurate; 2) skeletal evidence of fertility is severely underestimating actual levels; 3) there was very rapid population growth in the earliest part of the sequence up to 1150 A.D., from which no skeletal evidence currently is available; or 4) the prehistoric sequence of New Zealand may have been longer than the generally accepted 1,000-1,200 years. These alternatives are examined, and a combination of the last two is found to be the most probable. The implications of this model for New Zealand prehistory and Oceanic paleodemography are discussed.

Abuse liability and clinical pharmacokinetics of alprazolam in alcoholic men.

The abuse liability of alprazolam was studied in 17 abstinent alcoholic and 12 control subjects. A single 1-mg oral dose of alprazolam was administered, and subjective effects were measured by scales modified from the Addiction Research Center Inventory (ARCI). Multiple blood samples for alprazolam measurement were drawn over 48 hours. No statistically significant differences in pharmacokinetic parameters were found between groups. Alcoholics had lower baseline scores on the ARCI-Morphine/Benzedrine Group Scale (euphoria) and had greater drug-induced changes than nonalcoholics. The findings suggest that alcoholics may be at high risk to abuse alprazolam because it has a positive mood effect not seen in nonalcoholics.