Hippocampal Gray Volumes Increase in Treatment-Resistant Depression Responding to Vagus Nerve Stimulation.

BACKGROUND: Changes in hippocampal gray matter volumes are proposed to be involved in pathogenesis, course, and treatment response of major depressive disorder. Converging evidence suggests that reduced neurogenesis may occur in treatment-resistant depression (TRD). Vagus nerve stimulation (VNS) is a well-defined, long-term brain stimulation treatment for TRD. However, its in vivo positive effect on hippocampal modulation as mechanism of action has never been investigated before in clinical studies. In this study, we intended to explore hippocampal volumetric changes and clinical antidepressant responses in patients with TRD after 6 and 12 months of treatment with VNS. METHODS: The TRD outpatients were evaluated for VNS implantation. Right and left hippocampal volumes in 6 TRD patients, who met the criteria for VNS treatment, were measured at baseline before the implantation and after 6 and 12 months. The patients were assessed using Beck Depression Inventory and Hamilton Depression Rating Scale at baseline and at follow-up visits. RESULTS: There was a statistically significant and progressive increase in right and left hippocampal volumes during the follow up (P < 0.05). Furthermore, patients showed a significant improvement on Hamilton Depression Rating Scale and Beck Depression Inventory scores (P < 0.05). CONCLUSIONS: Our data suggest a VNS modulatory effect on hippocampal plasticity as measured by hippocampal gray volume increase in TRD patients. These preliminary findings indicate the fundamental role of hippocampal remodeling as a marker of response to VNS in TRD.

Evidence of language-related left hypofrontality in Major Depression: An EEG Beta band study.

Major depression (MDD) has been associated with an altered EEG frontal asymmetry measured in resting state; nevertheless, this association has showed a weak consistency across studies. In the present study, which starts from an evolutionistic view of psychiatric disorders, we investigated frontal asymmetry in MDD, using language as a probe to test the integrity of large inter- and intra-hemispheric networks and processes. Thirty MDD patients (22 women) and 32 matched controls (HC) were recruited for an EEG recording in resting state and during two linguistic tasks, phonological and semantic. Normalized alpha and beta EEG spectral bands were measured across all three conditions in the two groups. EEG alpha amplitude showed no hemispheric asymmetry, regardless of group, both at rest and during linguistic tasks. During resting state, analysis of EEG beta revealed a lack of hemispheric asymmetry in both groups, but during linguistic tasks, HC exhibited the typical greater left frontal beta activation, whereas MDD patients showed a lack of frontal asymmetry and a significantly lower activation of left frontal sites. In depressed patients, positive affect was negatively correlated with depression levels and positively correlated with left frontal EEG beta amplitude. Language represents the human process that requires the largest level of integration between and within the hemispheres; thus, language asymmetry was a valid probe to test the left frontal alteration encompassing highly impairing psychiatric disorders, such as schizophrenia and MDD. Indeed, these severe diseases are marked by delusions, ruminations, thought disorders, and hallucinations, all of which have a clear linguistic or metalinguistic basis.

Following "the Roots" of Kratom (Mitragyna speciosa): The Evolution of an Enhancer from a Traditional Use to Increase Work and Productivity in Southeast Asia to a Recreational Psychoactive Drug in Western Countries.

The use of substances to enhance human abilities is a constant and cross-cultural feature in the evolution of humanity. Although much has changed over time, the availability on the Internet, often supported by misleading marketing strategies, has made their use even more likely and risky. This paper will explore the case of Mitragyna speciosa Korth. (kratom), a tropical tree used traditionally to combat fatigue and improve work productivity among farm populations in Southeast Asia, which has recently become popular as novel psychoactive substance in Western countries. Specifically, it (i) reviews the state of the art on kratom pharmacology and identification; (ii) provides a comprehensive overview of kratom use cross-culturally; (iii) explores the subjective experiences of users; (iv) identifies potential risks and side-effects related to its consumption. Finally, it concludes that the use of kratom is not negligible, especially for self-medication, and more clinical, pharmacological, and socioanthropological studies as well as a better international collaboration are needed to tackle this marginally explored phenomenon.