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Recent longitudinal neuroimaging studies in patients with electroconvulsive therapy (ECT) suggest local effects of electric stimulation (lateralized) occur in tandem with global seizure activity (generalized). We used electric field (EF) modeling in 151 ECT treated patients with depression to determine the regional relationships between EF, unbiased longitudinal volume change, and antidepressant response across 85 brain regions. The majority of regional volumes increased significantly, and volumetric changes correlated with regional electric field (t = 3.77, df = 83, r = 0.38, p=0.0003). After controlling for nuisance variables (age, treatment number, and study site), we identified two regions (left amygdala and left hippocampus) with a strong relationship between EF and volume change (FDR corrected p, eLife digest Electroconvulsive therapy, or ECT for short, can be an effective treatment for severe depression. Many patients who do not respond to medication find that their symptoms improve after ECT. During an ECT session, the patient is placed under general anesthesia and two electrodes are attached to the scalp to produce an electric field that generates currents within the brain. These currents activate neurons and make them fire, causing a seizure, but it remains unclear how this reduces symptoms of depression. For many years, researchers thought that the induced seizure must be key to the beneficial effects of ECT, but recent studies have cast doubt on this idea. They show that increasing the strength of the electric field alters the clinical effects of ECT, without affecting the seizure. This suggests that the benefits of ECT depend on the electric field itself. Argyelan et al. now show that electric fields affect the brain by making a part of the brain known as the gray matter expand. In a large multinational study, 151 patients with severe depression underwent brain scans before and after a course of ECT. The scans revealed that the gray matter of the patients’ brains expanded during the treatment. The patients who experienced the strongest electric fields showed the largest increase in brain volume, and individual brain areas expanded if the electric field within them exceeded a certain threshold. This effect was particularly striking in two areas, the hippocampus and the amygdala. Both of these areas are critical for mood and memory. Further studies are needed to determine why the brain expands after ECT, and how long the effect lasts. Another puzzle is why the improvements in depression that the patients reported after their treatment did not correlate with changes in brain volume. Disentangling the relationships between ECT, brain volume and depression will ultimately help develop more robust treatments for this disabling condition.

Adverse experiences early in life impair cognitive function both in rodents and humans. In humans this increases the vulnerability to develop mental illnesses while in the rodent brain early life stress (ELS) abnormalities are associated with changes in synaptic plasticity, excitability and microstructure. Detailed information on the effects of ELS on rodent brain structural integrity at large and connectivity within the brain is currently lacking; this information is highly relevant for understanding the mechanism by which early life stress predisposes to mental illnesses.Here, we exposed rats to 24 hours of maternal deprivation (MD) at postnatal day 3, a paradigm known to increase corticosterone levels and thereby activate glucocorticoid receptors in the brain. Using structural magnetic resonance imaging we examined: i) volumetric changes and white/grey matter properties of the whole cerebrum and of specific brain areas; and ii) whether potential alterations could be normalized by blocking glucocorticoid receptors with mifepristone during the critical developmental window of early adolescence, i.e. between postnatal days 26 and 28.The results show that MD caused a volumetric reduction of the prefrontal cortex, particularly the ventromedial part, and the orbitofrontal cortex. Within the whole cerebrum, white (relative to grey) matter volume was decreased and region-specifically in prefrontal cortex and dorsomedial striatum following MD. A trend was found for the hippocampus. Grey matter fractions were not affected. Treatment with mifepristone did not normalize these changes.This study indicates that early life stress in rodents has long lasting consequences for the volume and structural integrity of the brain. However, changes were relatively modest and-unlike behavior-not mitigated by blockade of glucocorticoid receptors during a critical developmental period.

Background: To date, research findings are inconsistent about whether the neuroanatomy in transgender persons resembles that of their natal sex or their gender identity. Moreover, few studies have examined the effects of long-term cross-sex hormonal treatment on neuroanatomy in this cohort. The purpose of the present study was to examine neuroanatomical differences in transgender persons after prolonged cross-sex hormone therapy. Methods: Eighteen transgender men (female-to-male), 17 transgender women (male-to-female), 30 nontransgender men (natal men), and 27 nontransgender women (natal women) completed a high-resolution structural magnetic resonance imaging scan at 3 T. Eligibility criteria for transgender persons were gender-affirming surgery and at least 2 years of cross-sex hormone therapy. Exclusion criteria for nontransgender persons were presence of psychiatric or neurological disorders. Results: The mean neuroanatomical volume for the amygdala, putamen, and corpus callosum differed between transgender women and natal women but not between transgender women and natal men. Differences between transgender men and natal men were found in several brain structures, including the medial temporal lobe structures and cerebellum. Differences between transgender men and natal women were found in the medial temporal lobe, nucleus accumbens, and 3rd ventricle. Sexual dimorphism between nontransgender men and women included larger cerebellar volumes and a smaller anterior corpus callosum in natal men than in natal women. The results remained stable after correcting for additional factors including age, total intracranial volume, anxiety, and depressive symptoms. Conclusions: Neuroanatomical differences were region specific between transgender persons and their natal sex as well as their gender identity, raising the possibility of a localized influence of sex hormones on neuroanatomy.

Cerebral gray matter (GM) volume decreases in normal aging with a parallel increase in intracranial cerebrospinal fluid (CSF) volume. There is considerable interindividual variation in these changes, and the consequences of age-related GM shrinkage and CSF expansion are unclear. The present study examined whether late adulthood brain structural differences are related to differences in temperament and character. Personality structures of 42 healthy aged adults (mean age 60 years) were examined together with global and regional GM, CSF, and white matter (WM) volumes calculated from structural magnetic resonance images using voxel-based morphometry (VBM). A positive relationship was seen between GM volume at the border of the temporal, parietal, and frontal cortices, and self-transcendence, a character personality trait that reflects mature creativity and spiritualism. The relationship remained significant after a conservative correction for multiple comparisons and it was seen both using uncorrected raw values and after a correction for the effects of age and sex. The results suggest that high self-transcendence, which has adaptive advantages in the later part of life, is associated with relatively greater temporal cortical GM volumes. (C) 2004 Elsevier Inc. All rights reserved.