OBJECTIVES:This study examined the impact of crossmodal response precueing on action preparation in young and older adults. METHODS:Young (n = 37; 18-30 years) and older (n = 36; 60-77 years) adults performed a crossmodal visual-auditory version of the precueing paradigm, using a 4-choice task with 3 precue types. Informative precues either referred to response modality (manual vs vocal) or abstract spatial response feature (left vs right key press or vocal response). Informative precues reduced the number of possible stimulus-response options from 4 to 2, whereas uninformative precues cued all 4 possible options. The precueing benefit was calculated as the performance difference between informative versus uninformative precues. In addition, the cue-target interval (CTI) was varied to examine the benefit of long preparation time. RESULTS:Response-modality precues led to better performance compared to spatial and uninformative precues. In response-modality precues, older adults benefited more from long preparation time than young adults. For older adults, spatial precues produced a speed-accuracy tradeoff relative to uninformative cues, with shorter response times but higher error rates, particularly when the CTI was long. DISCUSSION:The pronounced increase in error rates with spatial precues when the CTI was long suggests that older adults had particular difficulty maintaining an abstract spatial response code without being able to specify the effector modality. Overall, the findings suggest that, in a complex multimodal setting involving variability in both stimulus modality and response modality, young and older adults are efficient when they are cued for a specific response modality.

This study explored the effect of mapping rule switching on motor preparation in young and older adults. Motor preparation was indexed by performance in the finger cuing task, which is a cued 4-choice reaction time (RT) task requiring a single keypress with 1 of 4 fingers (index and middle fingers of both hands). Mapping rule switching required switching between two possible mapping rules implemented via spatially compatible procues and spatially incompatible anticues. These informative cues preceded the target signal at five different time intervals (100–850 ms) to assess the temporal dynamics of preparatory control relative to a non-informative (control) cue. In the single-mapping condition, procues and anticues were administered in separate trial blocks. In the mixed-mapping condition, procues and anticues were randomly intermixed, with a mapping rule cue appearing at trial onset. Analyses of (absolute) RTs and (proportional) cuing effects in single-mapping and mixed-mapping conditions revealed greater preparation benefits for procues than anticues (only at short preparation intervals), and smaller preparation benefits for older than younger adults (only at longer preparation intervals). In both age groups, switching between mapping rules in the mixed-mapping condition created mixing costs (relative to single-mapping), reflecting substantial deficits in motor preparation, and more so at longer preparation intervals where proactive control dominates. These findings reveal a strong impact of mapping rule switching on motor preparation. We propose that activating a new mapping rule and preparing an action both require updating operations in working memory that bias response selection mechanisms.

Objectives: The metabolic syndrome is associated with cardiovascular diseases and cognitive decline. The egg protein hydrolysate NWT-03 has shown to improve cardiovascular risk factors in humans. This study investigated whether NWT-03 also has an effect on cognitive function. Methods: Men and women with the metabolic syndrome (n = 76) with a mean age of 60 +/- 10 years participated in this randomized, double-blind, placebo-controlled, cross-over trial with an intervention (5 g/day NWT-03) and control period (5 g/day maltodextrin) of 4 weeks separated by a wash-out period of 2-8 weeks. Cognitive function was assessed with the anti-cue reaction time test (impulse control) and psychomotor vigilance test (sustained attention) at day 0, 2, and 27 of both periods. Serum brain-derived neurotrophic factor (BDNF) concentrations were measured at the start and end of both periods. Results: NWT-03 consumption significantly improved the change (day 27 - day 0) in response times of the anti-cue reaction time test compared with the control period (P < 0.001), but not of the psychomotor vigilance test (P = 0.487). Serum BDNF concentrations of all subjects did not significantly change (P = 0.241). Conclusion: NWT-03 has the ability to improve cognitive function within the executive function domain. The underlying mechanism warrants further research and could either be indirect via inhibition of dipeptidyl peptidase 4 (DPP4) or direct via passage of small peptides over the blood-brain barrier inducing local effects.

Personal comfort systems (PCS) that warm or cool local body parts promise individual thermal comfort, energy saving and (metabolic) health in non-neutral thermal environments. However, research on work performance while using a PCS is scarce. We previously tested a PCS that warms the extremities and cools the head and reported that the PCS improved thermal comfort during a ramp of 17-23C but did not at a stable temperature of 25C. In the current study, its effects on cognitive performance, subjective measures and task-induced heart rate measures are investigated. Eighteen participants completed two randomized, eight-hour-long dynamic office scenarios: one is PCS scenario and another one is without PCS scenario. The results show warming the extremities slightly slowed reaction time for a simple task at 19C (p < 0.05) whereas it exerted no effect on complex task performance in 17-21t. At 25C however, cooling the head improved complex task performance (p = 0.053), which derived from participants' effort increase, whereas it did not affect simple task performance. These findings suggest that the PCS' effects on cogni-tive performance depended on the task type. Cooling the head, independent from its influence on thermal comfort, plays a significant role in complex cognitive performance in slightly warm conditions.(c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Preparatory cues facilitate performance in speeded choice tasks. It is debated, however, whether the lateralized neuro-anatomical organization of the human motor system contributes to this facilitation. To investigate this issue, we examined response preparation in a finger-cuing task using two conditions. In the hands adjacent condition, the hands were placed adjacently to each other with index and middle fingers placed on four linearly arrayed response keys. In the overlapped hand placement condition, the fingers of different hands alternated, thus dissociating hand and spatial position factors. Preparatory cues specified a subset of two fingers. Left-right cues specified the two leftmost or two rightmost fingers. Inner-outer cues specified the two inner or outer fingers. Alternate cues specified the first and third, or the second and fourth finger in the response set. In addition to reaction time and response errors, we measured the pupillary response to assess the cognitive processing load associated with response preparation. Results showed stronger pupil dilations (and also longer RTs and more errors) for the overlapped than for the adjacent hand placement condition, reflecting an overall increase in cognitive processing load. Furthermore, the negative impact of overlapping the hands on pupil dilation interacted with cue type, indicating that left-right cues (associated with two fingers on one hand) suffered most from overlapping the hands. With the hands overlapped, alternate cues (now associated with two fingers on the same hand) produced the shortest RTs. These findings demonstrate the importance of motoric factors in response preparation.

Several studies have reported that proactive motor control in a cued four-finger choice reaction task proceeds more efficiently with a 2-hands motor set (two fingers on each hand) than with a 1-hand motor set (four fingers on one hand). According to the Grouping Model, this is because the 2-hands motor set recruits distinct left and right hand representations located in separate cerebral hemispheres, whereas the 1-hand motor set recruits partially overlapping neural areas grouped together in one hemisphere. The latter neural organization increases neuromotor noise, thereby complicating proactive motor selection. The present study examined the effect of older age on the 2-hands motor selection advantage. A group of young and a group of older adults performed two proactive motor tasks—the procue task and the anticue task—with two motor sets: a 2-hands and 1-hand set. Predictive cues preceded the target signal at five different time intervals (100–850 ms), allowing advance selection of 2 out of 4 fingers. Older adults showed longer reaction times and smaller cueing benefits compared to younger adults. Overall, cueing benefits were greater, and accrued faster, with the 2-hands than with the 1-hand motor set, reflecting the beneficial impact of the neuroanatomical hand distinction. Importantly, the 2-hands advantage was substantially greater in the older age group, suggesting that the hand distinction might abate age-related neural dedifferentiation. These findings highlight the impact of cortical representational distinctiveness in proactive motor control, especially in older age.

Cognitive decline is associated with lifestyle-related factors such as overweight, blood pressure, and dietary composition. Studies have reported beneficial effects of dietary anthocyanins on cognition in older adults and children. However, the effect of anthocyanin-rich Aronia melanocarpa extract (AME) on cognition is unknown. Therefore, this study aimed to determine the effect of long-term supplementation with AME on cognitive performance, mood, and vascular function in healthy, middle-aged, overweight adults. In a randomized double-blind placebo-controlled parallel study, 101 participants either consumed 90 mg AME, 150 mg AME, or placebo for 24 weeks. The grooved pegboard test, number cross-out test, and Stroop test were performed as measures for psychomotor speed, attention, and cognitive flexibility. Mood was evaluated with a visual analogue scale, serum brain-derived neurotrophic factor (BDNF) was determined, and vascular function was assessed by carotid ultrasounds and blood pressure measurements. AME improved psychomotor speed compared to placebo (90 mg AME: change = −3.37; p = 0.009). Furthermore, 150 mg AME decreased brachial diastolic blood pressure compared to 90 mg AME (change = 2.44; p = 0.011), but not compared to placebo. Attention, cognitive flexibility, BDNF, and other vascular parameters were not affected. In conclusion, AME supplementation showed an indication of beneficial effects on cognitive performance and blood pressure in individuals at risk of cognitive decline.

Background Physical activity may attenuate age-related cognitive decline by improving cerebrovascular function. The aim of this study was therefore to investigate effects of aerobic exercise training on cerebral blood flow (CBF), which is a sensitive physiological marker of cerebrovascular function, in sedentary older men. Methods Seventeen apparently healthy men, aged 60–70 years and with a BMI between 25 and 35 kg/m2, were included in a randomized, controlled cross-over trial. Study participants were randomly allocated to a fully-supervised, progressive, aerobic exercise training or no-exercise control period for 8 weeks, separated by a 12-week wash-out period. Measurements at the end of each period included aerobic fitness evaluated using peak oxygen consumption during incremental exercise (VO2peak), CBF measured with pseudo-continuous arterial spin labeling magnetic resonance imaging, and post-load glucose responses determined using an oral glucose tolerance test (OGTT). Furthermore, cognitive performance was assessed in the domains of executive function, memory, and psychomotor speed. Results VO2peak significantly increased following aerobic exercise training compared to no-exercise control by 262 ± 236 mL (P < 0.001). CBF was increased by 27% bilaterally in the frontal lobe, particularly the subcallosal and anterior cingulate gyrus (cluster volume: 1008 mm3; P < 0.05), while CBF was reduced by 19% in the right medial temporal lobe, mainly temporal fusiform gyrus (cluster volume: 408 mm3; P < 0.05). Mean post-load glucose concentrations determined using an OGTT decreased by 0.33 ± 0.63 mmol/L (P = 0.049). Furthermore, executive function improved as the latency of response was reduced by 5% (P = 0.034), but no changes were observed in memory or psychomotor speed. Conclusion Aerobic exercise training improves regional CBF in sedentary older men. These changes in CBF may underlie exercise-induced beneficial effects on executive function, which could be partly mediated by improvements in glucose metabolism. This clinical trial is registered on ClinicalTrials.gov as NCT03272061.

Background: We investigated whether substituting sitting with standing and self-perceived light walking in free-living conditions would improve cardiometabolic risk factors, mood, and cognition in overweight/obese adults. Methods: In a randomized, cross-over study, 24 (m/f: 13/11) sedentary overweight/obese participants (64 ± 7 years, BMI 29 ± 2 kg/m2) followed two activity regimens of each 4 days in free-living conditions: “Sit”: sitting 13.5 h/day, standing 1.4 h/day, self-perceived light-intensity walking 0.7 h/day; for “SitLess” these activities lasted 7.6, 4.0, and 4.3 h/day, respectively. Meals were standardized and physical activity was assessed by accelerometry (activPAL). Insulin sensitivity (expressed as Matsuda-index based on an oral glucose tolerance test), circulating lipids, blood pressure, mood (pleasantness and arousal), and cognition were assessed on the morning after the activity regimens. Quality of life and sleep were assessed on the last day of the activity regimens. Results: We observed that AUC (0–190 min) for insulin decreased by 20% after SitLess vs. Sit [10,125 (656) vs. 12,633 (818); p = 0.006]. Insulin sensitivity improved by 16% after SitLess vs. Sit [Matsuda-index, mean (SEM): 6.45 (0.25) vs. 5.58 (0.25) respectively; p = 0.007]. Fasting triglycerides, non-HDL-cholesterol, and apolipoprotein B decreased by 32, 7, and 4% respectively, whereas HDL-cholesterol increased by 7% after SitLess vs. Sit (all p < 0.01). Diastolic blood pressure was lower after SitLess vs. Sit (p < 0.05). Pleasantness (as one marker of mood status) after the oral glucose tolerance test was higher after SitLess vs. Sit (p < 0.05). There was no significant difference between regimens for cognition, quality of life and sleep. Conclusions: Reducing sitting time in free-living conditions markedly improved insulin sensitivity, circulating lipids, and diastolic blood pressure. Substituting sitting with standing and self-perceived light walking is an effective strategy to improve cardiometabolic risk factors in overweight/obese subjects.

We investigated two components of proactive cognitive control, response facilitation and response inhibition, in an adult lifespan sample (N=544, age range=18-91years) by administering two response-preparation tasks: a procue task, primarily involving facilitation, and an anticue task, involving both facilitation and inhibition. Cues in both tasks corresponded with the index and middle fingers of either the left or right hand. After a random preparation interval (PI) of 100-850ms following the onset of the cue signal, a single-target stimulus indicated the required response. Where procues were spatially aligned with the two fingers of the responding hand, anticues consistently indicated the two fingers of the opposite hand, requiring a remapping of cue location and response hand. This remapping requires inhibition to suppress the automatic activation of the ipsilateral responses. Previous research revealed typical reaction time (RT) profiles for procues and anticues as a function of PI. Whereas procues generate RT benefits (relative to a neutral-cue condition) already at short PIs, which increase with longer PIs, anticues generate RT costs at short PIs and RT benefits at longer PIs. Our results showed that, in the anticue task, older participants needed more preparation time to turn RT costs into RT benefits than younger participants, revealing an age-related deficit of response inhibition. Moreover, in both tasks, older participants were less able to increase RT benefits with longer PIs, revealing a deficit of response facilitation. We conclude that both facilitatory and inhibitory impairments contribute to age-related deficiencies in proactive cognitive control.

Background: Human motor behaviors are characterized by both, reactive and proactive mechanisms. Yet, studies investigating the neural correlates of motor behavior almost exclusively focused on reactive motor processes. Here, we employed the pro-/anti-cue motor preparation paradigm to systematically study proactive motor control in an imaging environment. In this paradigm, either pro-or anti-cues are presented in a blocked design. Four fingers (two from each hand) are mapped onto four visual target locations. Visual targets require a speeded response by one corresponding finger, but, most importantly, they are preceded by visual cues that are congruent ("pro-cue"), incongruent ("anti-cue"), or neutral with respect to the responding hand. With short cue-target intervals, congruence effects are based on automatic motor priming of the correct hand (in case of pro-cues) or incorrect hand (in case of anti-cues), generating, respectively, reaction time benefits or reaction time costs relative to the neutral-cue. With longer cu-target intervals, slower top-down processes become effective, transforming early anti-cue interference into late anti-cue facilitation.Methods: We adapted this paradigm to be compatible with neuroimaging, tested and validated it behaviorally-both inside and outside the imaging environment-and -implemented it in a whole-brain functional magnetic resonance imaging study.Results and Conclusion: Our imaging results indicate that pro-cues elicited much less neural activation than did anti-cues, the latter recruiting well-known cognitive top-down networks related to attention, response inhibition, and error monitoring/signaling, thereby revealing high-level influences on proactive motor processes.

We investigated the effects of age on proactive and reactive cognitive control in a large population sample of 809 individuals, ranging in age between 5 and 97 years. For that purpose, we used an anticue paradigm, which required a consistent remapping of cue location and response hand: Left-sided cues required right-hand responses and vice versa. After a random preparation interval of 100-850 ms, these anticues were followed by a target stimulus, which prompted a response with the index or middle finger of 1 of 2 hands. A neutral control condition involved uninformative cues, indicating all 4 possible response locations. The primary outcome measure was the difference between neutral and anticue reaction time (RT). Negative values indicated RT costs of the anticue, relative to the neutral condition, reflecting reactive cognitive control. Positive values indicated RT benefits, reflecting proactive cognitive control. Results were twofold. First, the switch from RT costs to benefits took place at longer preparation intervals in the youngest and oldest age groups than in the intermediate age groups. Second, irrespective of preparation interval, anticue performance followed an inverted U-shaped trajectory as a function of age, with a relatively steep improvement during childhood and adolescence, relative stability between 26 and 60 years, and a slightly accelerating decline into old age. Both patterns of results suggest an age-related transition from a primarily reactive, to a primarily proactive mode of cognitive control in early life and back again from a primarily proactive, to a primarily reactive mode of control in later life. (PsycINFO Database Record

This study uses a novel behavioral paradigm-the anticue task-to investigate the temporal dynamics of proactive control aimed at the resolution of response conflict in the manual motor system. The anticue task is a 4-choice reaction time (RT) task, with left and right anticues indicating mirror-symmetrical response hands. In particular, anticues require participants to prepare fingers on the hand opposite to the side of the cue (counter-corresponding mapping), which contrasts with the more standard procues that prompt participants to prepare fingers on the hand spatially in line with the cue (corresponding mapping). In Experiment 1, we examined the effects of anticues and procues as a function of cue-target interval (range: 100-850ms). Results showed that procues produced RT benefits (relative to neutral cues), which increased with longer cue-target intervals. Anticues, however, produced RT costs with short cue-target intervals and RT benefits with longer cue-target intervals. These findings support the view that anticues are mediated by a time-consuming, proactive control process that, using inhibition and activation, redirects the initial but wrong activation of the ipsilateral hand to the correct contralateral hand. In Experiment 2, we used a simple detection response to test, and reject, an alternative (attentional) account of these findings. Theoretical and practical implications are discussed in the context of dual-route models of response selection, the activation-suppression model, and related experimental protocols such as antisaccade, Simon, Stroop, Eriksen flanker, and task switching paradigms.

Maintenance of cognitive abilities is important for elderly to stay independent. With the aging of the population, the call for modifiable factors is emerging. Dietary protein might improve cognitive performance; however, this has hardly been studied. Therefore, we studied the impact of 24-week dietary protein supplementation on cognitive performance in pre-frail and frail elderly people.

Physical activity has been proposed as one of the most effective strategies to prevent cognitive decline. Protein supplementation may exert an additive effect. The effect of resistance-type exercise training with or without protein supplementation on cognitive functioning in frail and pre-frail elderly people was assessed in a secondary analysis. Two 24-week, double-blind, randomized, placebo-controlled intervention studies were carried out in parallel. Subjects performed a resistance-type exercise program of two sessions per week (n = 62) or no exercise program (n = 65). In both studies, subjects were randomly allocated to either a protein (2 Chi 15 g daily) or a placebo drink. Cognitive functioning was assessed with a neuropsychological test battery focusing on the cognitive domains episodic memory, attention and working memory, information processing speed, and executive functioning. In frail and pre-frail elderly, resistance-type exercise training in combination with protein supplementation improved information processing speed (changes in domain score 0.08 +/- 0.51 versus 0.23 +/- 0.19 in the non-exercise group, p = 0.04). Exercise training without protein supplementation was beneficial for attention and working memory (changes in domain scores 035 +/- 0.70 versus 0.12 +/- 0.69 in the non-exercise group, p = 0.02). There were no significant differences among the intervention groups on the other cognitive tests or domain scores. (C) 2013 Elsevier Ireland Ltd. All rights reserved.

It is well reported that movement times to the first target in a two-target sequence are slower than when a single target response is required. This one-target advantage has been shown to emerge when the two-target sequence is performed with the same limb and when the first and second segments within the sequence are performed with different limbs (i.e., when there is a switch between limbs at the first target). The present study examined the functional dependency between response segments in both single and two limb sequential aiming by varying the accuracy demands at the first and second target. Results revealed that, for both one and two limb conditions, the one-target advantage was present with large first targets but not with small first targets. Additionally, when the first target was large and the second target was small, spatial variability at the first target was significantly less (or constrained more) in both one and two limb conditions compared to conditions requiring only a single target response. These findings suggest that similar principles underlie the one-target advantage in both single and two limb sequential movements.

Successful motor performance requires a process of response selection that chooses the correct response out of a set of possible ones. Most theories of response selection assume that this selection process operates on spatial codes, which define the location of stimuli and responses in environmental coordinates, with little or no role for the anatomical codes of the effectors involved. In this study, we tested this assumption by investigating response-repetition effects in a response-cuing paradigm using two motor sets (fingers on one hand vs. fingers on two hands). Reaction time results demonstrated a robust response-repetition benefit that was greater for the one-hand set than for the two-hands set. Furthermore, with the one-hand set the repetition benefit was independent of cue type and cue-stimulus interval on the previous trial, whereas with the two-hands set it was strongly modulated by these two factors. These differential response-repetition effects for one- and two-hands motor sets demonstrate the important role of the neuro-anatomical hand distinction in response selection, thereby supporting multiple coding notions.

Movement times to a single target are typically shorter compared to when movement to a second target is required. This one target movement time advantage has been shown to emerge when participants use a single hand throughout the target sequence and when there is a switch between hands at the first target. Our goal was to investigate the lacuna in the movement integration literature surrounding the interactive effects between switching hands and changing movement direction at the first target. Participants performed rapid hand movements in five conditions; movements to a single target; two target movements with a single hand in which the second target required an extension or reversal in direction; and movements to two targets where the hands were switched at the first target and the second target required an extension or reversal in direction. The significance of including these latter two (multiple hand-multiple direction) movements meant that for the first time research could differentiate between peripheral and central processes within movement integration strategies. Reaction times were significantly shorter in the single task compared to the two target tasks. More importantly, movement times to the first target were significantly shorter in the single target task compared to all two target tasks (reflecting the so-called one target advantage), except when the second movement was a reversal movement with the same hand. These findings demonstrate for the first time the contrasting effects of movement integration at central and peripheral levels.

This study examined the ability of participants to strategically adapt their level of response preparation to the predictive value of preparatory cues. Participants performed the finger-precuing task under three levels of cue validity: 100, 75 and 50% valid. Response preparation was indexed by means of reaction time (RT) and pupil dilation, the latter providing a psychophysiological index of invested effort. Results showed a systematic increase in RT benefits (generated by valid cues) and RT costs (generated by invalid cues) with increments in the predictive value of cues. Converging with these behavioural effects, pupil dilation also increased systematically with greater cue validity during the cue-stimulus interval, suggesting more effortful response preparation with increases in cue validity. Together, these findings confirm the hypothesis that response preparation is flexible and that it can be strategically allocated in proportion to the relative frequency of valid/invalid preparatory cues.

Background: The loss of muscle mass with aging reduces muscle strength, impairs functional capacity, and increases the risk of developing chronic metabolic disease. It has been suggested that the development of type 2 diabetes results in a more rapid decline in muscle mass, strength, and functional capacity.Objective: To investigate the impact of type 2 diabetes on muscle mass, strength, and functional capacity in an older population.Methods: Muscle mass (DXA and muscle biopsies), strength (1-repetition maximum), functional capacity (sit-to-stand test and handgrip strength), and reaction time performance (computer task) were compared between 60 older men with type 2 diabetes (71 +/- 1 years) and 32 age-matched normoglycemic controls (70 +/- 1 years). Data were analyzed using ANCOVA to adjust for several potential confounders.Results: Leg lean mass and appendicular skeletal muscle mass were significantly lower in older men with type 2 diabetes (19.1 +/- 0.3 and 25.9 +/- 0.4 kg, respectively) compared with normoglycemic controls (19.7 +/- 0.3 and 26.7 +/- 0.5 kg, respectively). Additionally, leg extension strength was significantly lower in the group with type 2 diabetes (84 +/- 2 vs 91 +/- 2 kg, respectively). In agreement, functional performance was impaired in the men with type 2 diabetes, with longer sit-to-stand time (9.1 +/- 0.4 vs 7.8 +/- 0.3 seconds) and lower handgrip strength (39.5 +/- 5.8 vs 44.6 +/- 6.1 kg) when compared with normoglycemic controls. However, muscle fiber size and reaction time performance did not differ between groups.Conclusion: Older patients with type 2 diabetes show an accelerated decline in leg lean mass, muscle strength, and functional capacity when compared with normoglycemic controls. Exercise intervention programs should be individualized to specifically target muscle mass, strength, and functional capacity in the older population with type 2 diabetes. Copyright (C) 2013 - American Medical Directors Association, Inc.