This narrative review examines literature pertaining to possible physiological explanations for observed cognitive benefits stemming from improvements to cardiovascular fitness following chronic aerobic exercise. Studies regarding exercise and cardiovascular fitness, angiogenesis, neuroinflammation in relation to IGF-1 signalling, regulation of neurotrophins, neurogenesis and plasticity, cognitive training, are briefly described. We propose that current evidence points towards a mechanism by which cardiovascular fitness improvements act to promote long-term angiogenesis and cerebral circulation. This important adaptation allows for increased delivery and upregulation of neurotrophins along with supporting factors to the brain, particularly to the hippocampal neurogenic niche, following acute exercise bouts. We propose a sequential timeline and approximate time scale for this mechanism, describing how these stages generate increased support for neurogenesis and brain plasticity in combination with cognitive training to provide long-term cognitive benefits and protection against age-related cognitive decline. Influences from age, gender and other variables are considered, and methodological factors that could be utilised in future studies to further clarify the proposed model are discussed.

It is now accepted that sub-clinical autistic traits are continuously distributed in the general population. It appears that there has been no prior research on the relationship between autistic traits and mental well-being. We explored the nature of such a relationship using multiple regression models. 227 non-clinical adults aged 18-50 years completed an online self-report questionnaire with measures including the Warwick-Edinburgh Mental Wellbeing Scale and the Broad Autism Phenotype Questionnaire (BAPQ). Of the BAPQ subscales, aloofness (social anhedonia) but not rigidity or pragmatic language problems was associated with decreased mental well-being when controlling for extraversion, neuroticism, depression, and self-reported physical health. This association was partially mediated by crisis support (the number of people a respondent felt they could turn to for help in the event of a serious personal crisis). The results suggest that aloofness is a significant negative predictor of mental well-being, and that autistic traits might not be best represented as a single unitary factor in the context of outcomes related to mental well-being. Implications pertaining to the importance of social support and the possible contributing role of low self-perceived social competence to aloofness are discussed.