MRC Centre for Synaptic Plasticity, Department of Anatomy, University of Bristol, Bristol BS8 1TD, UK.
Published: July 2009
AI Article Synopsis
Article Abstract
Recent, convergent evidence places the anterior thalamic nuclei at the heart of diencephalic amnesia. However, the reasons for the severe memory loss in diencephalic amnesia remain unknown. A potential clue comes from the dense, reciprocal connections between the anterior thalamic nuclei and retrosplenial cortex, another region vital for memory. We now report a loss of synaptic plasticity [long-term depression (LTD)] in rat retrosplenial cortex slices months following an anterior thalamic lesion. The loss of LTD was lamina-specific, occurring only in superficial layers of the cortex and was associated with a decrease in GABA(A)-mediated inhibitory transmission. As retrosplenial cortex is itself vital for memory, this distal lesion effect will amplify the impact of anterior thalamic lesions. These findings not only provide novel insights into the functional pathology of diencephalic amnesia and have implications for the aetiology of the posterior cingulate hypoactivity in Alzheimer's disease, but also show how distal changes in plasticity could contribute to diaschisis.
Objective: This study aims to evaluate the efficacy and safety of deep brain stimulation (DBS) of the medial pulvinar nucleus (PuM) in reducing seizure frequency and addressing comorbidities in patients with drug and vagal nerve-resistant focal epilepsy.
Methods: This is an open-label prospective treatment trial with a planned enrollment of 12 patients suffering from medically refractory epilepsy (Clinical trial gov NCT04692701), for which the interim 12-month post-implantation results for the first 6 patients are being reported. Inclusion criteria were focal epilepsy not suitable for or after failed surgical intervention and previous failure of neurostimulation therapies (vagus nerve stimulation or anterior thalamic nucleus DBS).
Background: Poststroke irritability (PSI) is common among stroke survivors and can lead to a poor quality of life, difficulties in social interactions, criticism from caregivers, and caregiver stress. The planned study will evaluate the clinical, neuropsychological, and magnetic resonance imaging (MRI) correlates of PSI in a cohort of stroke survivors. In addition, the study will examine the 15-month progression of PSI.
Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, China; Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, China. Electronic address:
Objective: The overlap of affective disturbance and psychosis considerably makes it complex to determine the etiology of bipolar disorder (BD) and develop targeted interventions. The present study aimed to determine the white matter microstructural alterations that distinguish between BD with psychosis (BDP) and BD with no psychosis (BDNP) to identify patients who may specifically benefit from appropriately effective treatments.
Methods: Diffusion-weighted magnetic resonance images were acquired from 38 participants with BDP, 52 participants with BDNP and 70 healthy controls (HCs).
PET and SPECT studies in treatment-resistant schizophrenia (TRS) have revealed significant alterations in regional cerebral blood flow (CBF) during clozapine treatment, which may vary according to the clinical response. Here, we used the more recent MRI approach of arterial spin labelling (ASL) to evaluate regional CBF in participants with TRS (N = 36) before starting treatment with clozapine compared to in healthy volunteers (N = 16). We then compared CBF in the TRS group, before and after 12 weeks of treatment with clozapine (N = 24); and examined the relationship of those differences against changes in Positive and Negative Syndrome Scale for Schizophrenia (PANSS) scores over the treatment period.
Introduction: White matter tracts that connect different parts of the brain comprise the structural connectome, which is essential to its operation. Assessing behavioral changes and brain health requires an understanding of these tracts. Diffusion tensor imaging (DTI), in particular, allows for the thorough viewing and characterization of these routes in tractography.
