Catecholaminergic modulation of the cost of cognitive control in healthy older adults

Abstract

Catecholamines have long been associated with cognitive control and value-based decision-making. More recently, we have shown that catecholamines also modulate valuebased decision-making about whether or not to engage in cognitive control. Yet it is unclear whether catecholamines influence these decisions by altering the subjective value of control. Thus, we tested whether tyrosine, a catecholamine precursor altered the subjective value of performing a demanding working memory task among healthy older adults (60-75 years). Contrary to our prediction, tyrosine administration did not significantly increase the subjective value of conducting an N-back task for reward, as a main effect. Instead, in line with our previous study, exploratory analyses indicated that drug effects varied as a function of participants' trait impulsivity scores. Specifically, tyrosine increased the subjective value of conducting an N-back task in low impulsive participants, while reducing its value in more impulsive participants. One implication of these findings is that the over-the-counter tyrosine supplements may be accompanied by an undermining effect on the motivation to perform demanding cognitive tasks, at least in certain older adults. Taken together, these findings indicate that catecholamines can alter cognitive control by modulating motivation (rather than just the ability) to exert cognitive control.

Baseline-dependent effect of dopamine’s precursor L-tyrosine on working memory gating but not updating

“…The baseline-dependent effect of L-tyrosine on gate opening is remarkably consistent with the well-established inverted-U curve relating dopamine activity and WM (Cools & D'Esposito, 2011), as well as previous literature showing state-dependent effects of L-tyrosine on cognitive control (Jongkees et al, 2015). Converging evidence that effects of L-tyrosine depend on baseline dopaminergic state in particular comes from a recent (preprinted) study in healthy older adults showing that L-tyrosine's effect on the willingness to exert cognitive control was predicted by individual trait impulsivity (Froböse, Westbrook, Bloemendaal, Aarts, & Cools, 2019), a correlate of dopamine activity in BG (Buckholtz et al, 2011). Together, these findings indicate that L-tyrosine can modulate both the ability and motivation to engage in cognitive control in a state-dependent manner.…”

Increased cognitive effort costs in healthy aging and preclinical Alzheimer’s disease.

“…The N-back version of COG-ED was used in this experiment, since it has a longer and more well-established history in the literature (A. Culbreth et al, 2016;Froböse et al, 2020;Westbrook et al, 2013Westbrook et al, , 2019. The version used here was similar to but developed independently of the version adopted in Experiment 1.…”

“…In terms of neurobiological mechanisms, valuations of cost and effort have been linked to specific brain regions and systems, including the ventromedial prefrontal cortex and striatum (Lopez-Gamundi et al, 2021; Westbrook et al, 2019), midbrain dopamine systems (Froböse et al, 2020; Westbrook & Braver, 2016; Westbrook et al, 2020), and the default mode network (Barnes et al, 2009; see Westbrook & Braver, 2015 for a full review). Here, we explore another possibility: that increases in amyloid pathology are associated with age-related differences in cognitive effort costs.…”

Human complex exploration strategies are extended via noradrenaline-modulated heuristics

“…(13,14)). This directly relates to an agents' motivation to perform a given task (11,15,16), as increasing an information demand in one process automatically reduces its availability for others (12). In real-world highly dynamic environments, this arbitration is critical as humans need to maintain resources for alternative opportunities (i.e.…”