Intellectual enrichment and genetic modifiers of cognition and brain volume in Huntington's disease

Mild cognitive impairment in Huntington's disease: challenges and outlooks

Although Huntington's disease (HD) has classically been viewed as an autosomal-dominant inherited neurodegenerative motor disorder, cognitive and/or behavioral changes are predominant and often an early manifestation of disease. About 40% of individuals in the presymptomatic period of HD meet the criteria for mild cognitive impairment, later progressing to dementia. The heterogenous spectrum of cognitive decline is characterized by deficits across multiple domains, particularly executive dysfunctions, but the underlying pathogenic mechanisms are still poorly understood. Investigating the pathophysiology of cognitive changes may give insight into important and early neurodegenerative events. Multimodal imaging revealed circuit-wide gray and white matter degenerative processes in several key brain regions, affecting prefronto-striatal/cortico-basal ganglia circuits and many other functional brain networks. Studies in transgenic animal models indicated early synaptic dysfunction, deficient neurotrophic transport and other molecular changes contributing to neuronal death. Synaptopathy within the cerebral cortex, striatum and hippocampus may be particularly important in mediating cognitive and neuropsychiatric manifestations of HD, although many other neuronal systems are involved. The interaction of mutant huntingtin protein (mHTT) with tau and its implication for cognitive impairment in HD is a matter of discussion. Further neuroimaging and neuropathological studies are warranted to better elucidate early pathophysiological mechanisms and to develop validated biomarkers to detect patients' cognitive status during the early stages of the condition significantly to implement effective preventing or management strategies.

Celebrating the life and research of BNA Past-President Colin Blakemore

Professor Sir Colin Blakemore was a remarkable neuroscientist, persuasive communicator, and brave advocate for animal research who, sadly, passed away in June 2022 from amyotrophic lateral sclerosis. His work helped establish the concept of neuronal plasticity, which was fundamental to our understanding of the postnatal brain and continues to impact our outlook on neurodegenerative disorders. The BNA2023 Festival of Neuroscience dedicated its last plenary session in his honour, bringing together five prominent neuroscientists whose careers were shaped by Professor Blakemore. Here, we summarise the speakers' reflections on how Colin's support, generosity, and foresight influenced their academic paths, inspired their research, and changed their outlook on life.