Gain without pain: Glucose promotes cognitive engagement and protects positive affect in older adults.

Abstract

When faced with a cognitively demanding task, older adults tend to disengage and withdraw effort. At the same time, their usual processing preference for positive information disappears. Providing glucose as an energy resource is known to improve cognitive performance and reinstate older adults' positivity preference. Here, we examined whether glucose can help older adults to exert more effort under high difficulty conditions, and if so, whether such increase is accompanied by a change in positive affect. Fifty-three young and 58 older adults consumed a glucose or a placebo drink and completed a memory-search task at three levels of difficulty. Cognitive engagement was measured through changes in heart rate (HR) and self-reported effort. After each memory-search block, participants completed an implicit emotion-assessment task. In both age groups, glucose produced increased HR (indicating higher task engagement) relative to placebo. In older but not in young adults, glucose also improved cognitive performance and increased positive affect. Subjective effort, in contrast, did not differ between the older-glucose and older-placebo groups. These results suggest that in older adults, glucose improves cognitive performance by promoting higher cognitive engagement while mitigating the subjective costs of effortful exertion. (PsycINFO Database Record

Sugar rush or sugar crash? A meta-analysis of carbohydrate effects on mood

“…Additionally, studies assessing the effects of CHO on cognition and mood have administered a wide variety of CHO types and doses, and have implemented different fasting intervals prior to CHO consumption to investigate the optimal conditions under which CHO effects are most prominent. Although the majority of studies in the area routinely administer glucose (Mantantzis et al, 2018(Mantantzis et al, , 2017Scholey and Fowles, 2002;Sünram-Lea et al, 2001), a number of other reports have opted for sucrose (van der Zwaluw et al, 2014;Zacchia et al, 1991), fructose (Miller et al, 2013), galactose (Duckworth et al, 2013), and isomaltulose (Dye et al, 2010;Young and Benton, 2014). This methodological choice could influence the magnitude of CHO-mood interactions as considerable differences exist in the way that each CHO is metabolized and converted into energy (see Bantle et al, 1983;Rippe and Angelopoulos, 2013).…”

Measuring distinct emotional states implicitly: The role of response speed.

“…Participants who had experienced a given emotion induction (sadness, anger, or fear) more frequently judged that the artist was trying to convey that emotion. Subsequent findings support the utility of this implicit assessment method (Bryant, Winer, Salem, & Nadorff, 2017; Holt, Furbert, & Sweetingham, 2019; Mantantzis, Maylor, & Schlaghecken, 2018; Wisneski & Skitka, 2017; also see Mackie & Smith, 2017; Wróbel, 2018).…”

Age differences in reactivity to daily general and Type 1 diabetes stressors.

“…The experience of a chronic illness and its associated daily stressors may make the affective experience more similar across young and older adults. In addition, the fact that adults of all ages were experiencing similar levels of blood glucose may relate to their similarities in affect, given recent work noting that the positivity effect may relate to glucose levels for older adults without diabetes (Mantantzis, Maylor, & Schlaghecken, 2018).…”