Neuroscience Ireland Conference 2025
Conference Speaker Profile
Prof. Richard Carson
Trinity College Dublin, Ireland;
Queen's University Belfast, Northern Ireland
Talk Title
Size matters. Age and sex-related variations in quantitative metrics derived from diffusion weighted imaging must be adjusted for brain size.
Talk Abstract
It is widely accepted that ageing brings about changes in both brain structure and function. For example, a common belief based on analyses of the blood-oxygenation-level-dependent BOLD signal derived from functional magnetic resonance imaging (fMRI) is that older adults show greater “brain activity” than young adults, particularly during tasks that might be deemed “less demanding”.
And yet, this is not matched by corresponding differences in functional positron emission tomography (fPET) measurements of glucose metabolism. This contrariety highlights that the inferences that can be made in relation to the physiological mechanisms that mediate age-related changes in brain function, are constrained by inherent limitations of the imaging techniques that can be applied to living humans.
In a similar vein, it has been demonstrated (Carson & Leemans, 2024) that several quantitative metrics (such as fractional anisotropy (FA)) derived from diffusion weighted imaging (DWI) tractography exhibit systematic associations with the length of the “streamlines” from which they are obtained. Since age-related decrease in brain volume have been widely documented (along with corresponding changes in the length of streamlines registered by DWI), the presence of these associations suggests that the temporal dynamics of lifespan changes in diffusion imaging derived measures of human brain white matter (such as FA) require quantitative re-evaluation. In a similar vein, as fibre tracts in the human brain are on average longer in males than in females, attributions of sex-differences in quantitative metrics derived from DWI tractography demand further scrutiny.
Speaker Biography
Richard Carson is Chair in Cognitive Neuroscience of Ageing in the School of Psychology and the Institute of Neuroscience at Trinity College Dublin. He grew up near Belfast, graduated from the University of Bristol, and was subsequently awarded his Ph.D. by Simon Fraser University in 1993.
He then held a series of research fellowships at the University of Queensland, before moving to Queen’s University Belfast in 2006, and to Trinity College Dublin in 2011. His additional appointments are as Chair in Psychology at Queen’s University Belfast and as an Honorary Professor at the University of Queensland.
His research focuses upon human brain plasticity, with a particular emphasis upon changes that occur across the lifespan, and therapeutic approaches to the remediation of functional movement capability following brain injury.