It’s been quite some time since I have done a Neury Thursday. But now that conference season has ended and I can sleep in my own bed, use my own reliable internet, return to my own crossfit gym, and stop spending nights and afternoons eating at restaurants and drinking wonderfully fermented beverages, I am re-motivated to discuss the latest current neuroscience research.
It’s very fitting that my first post relates to a study, in part, that we are attempt to get published; the interactions of aging and exercise on chronic ethanol intake. Although we did not undertake any measures of dopaminergic signaling, I postulate that some of the changes that we saw in our study were due to diminished dopamine binding. In a recent Journal of Neuroscience paper published by various aging-focused research institutes, performance on a cognitive task was influenced by aging-related changes in dopaminergic binding in classic higher-order cortical areas controlling attention, decision-making, and impulsivity: the anterior cingulate cortex, dorsolateral prefrontal cortex, and parietal cortex. Because this study was conducted in humans and not an animal model, typical measures of dopaminergic signaling, namely PET imaging and radioligand binding, were used.
A wonderful schematic of the experimental design and its aims was (thankfully) provided in the paper.
As you can see in this figure, there is substantially more binding of dopamine to D1 receptors, indicated by warmer colors, in the young vs. old adults.
Moreover, this study bridges the gap in knowledge in understanding the neurobiological underpinnings of aging- and even compounded psychiatric (Parkinson’s, schizophrenic) cognitive decline.
Stuart W. S. MacDonald, Sari Karlsson, Anna Rieckmann, Lars Nyberg, and Lars Ba¨ckman, PhD (2012). Aging-Related Increases in Behavioral Variability: Relations
to Losses of Dopamine D1 Receptors Journal of Neuroscience DOI: 10.1523/JNEUROSCI.5474-11.2012