Decision making in the ageing brain: changes in affective and motivational circuits

Abstract

As the global population ages, older decision makers will be required to take greater responsibility for their own physical, psychological and financial well-being. With this in mind, researchers have begun to examine the effects of ageing on decision making and associated neural circuits. A new “affect, integration, motivation” (or AIM) framework may help clarify how affective and motivational circuits support decision making. Recent research has shed light on whether and how ageing influences these circuits, providing an interdisciplinary account of how ageing can alter decision making.

Altered behavioral and neural responsiveness to counterfactual gains in the elderly

“…Task-related activity in the fronto-striatal circuit was also affected by age, where older adults generally showed stronger responses to factual and counterfactual consequences in the striatum, but a non-significant correlation with reward predictions in the vmPFC. Our findings are in general agreement with previous literature showing that relatively poor decision making in multialternative choice tasks in older adults is related to aberrant reward prediction and prediction error processing in this fronto-striatal circuit (Chowdhury et al, 2013;Eppinger, Walter et al, 2013;Eppinger, Nystrom, et al, 2012;Eppinger, Schuck, et al, 2013;Grady, 2012;Hedden & Gabrieli, 2004;Rademacher, Saalma, Grunder, & Sprecklemeyer, 2014;SamanezLarkin et al, 2007;Samanez-Larkin et al, 2011;Samanez-Larkin et al, 2014;Samanez-Larkin & Knutson, 2015;Vink et al, 2015;), and extends these findings to include altered processing of counterfactual consequences. Finally, this study advocates the modelbased fMRI experimental design to study both behavioral and neural systems for decision making between age groups but cautions that model fits be carefully taken into account when drawing conclusions about group differences.…”

Inflammation Effects on Motivation and Motor Activity: Role of Dopamine

“…Indeed, increased inflammation (plasma concentrations of CRP as well as cytokines and their soluble receptors) was associated with decreased functional connectivity between the ventral striatum and vmPFC, and the dorsal striatum and the vmPFC and pre-supplementary motor area (pre-SMA), which correlated with self-reported symptoms of anhedonia and objective measures of psychomotor slowing, respectively . Interestingly, dorsal striatum and pre-SMA/SMA are key components of corticostriatal circuitry involved in linking motivation to motor output (Haber and Knutson, 2010;Samanez-Larkin and Knutson, 2015), and like the ventral striatum, vmPFC is part of classic reward circuitry that receives significant mesocorticolimbic DA innervation (Diekhof et al, 2012;Russo and Nestler, 2013). Accordingly, inflammation-related decreases in corticostriatal connectivity within reward and motor circuitry in depression may involve cytokine-induced decreases in DA, and have potential for reversal with pharmacological strategies that increase DA availability or receptor signaling (see the sections 'Mechanisms of inflammation effects on dopamine synthesis and release' and 'Potential therapeutic targets for inflammation effects on dopamine' below for further discussion; Felger and Miller, 2012).…”

The involvement of BDNF, NGF and GDNF in aging and Alzheimer's disease

“…Both aging process and AD are characterized by a progressive deterioration of learning and memory [4][5][6]. This strong relationship between aging and AD is important to investigate the time which they overlap, as well as, the pathophysiological mechanism in each event such as the involvement of the neurotrophic factors in these processes.…”

“…Cognitive deficits are the most common consequences of aging process and AD [4][5][6]. AD is one of the most common and devastating agingrelated neurodegenerative diseases.…”