scholarly journals The facilitative effects of glucose ingestion on memory retrieval in younger and older adults: is task difficulty or task domain critical?

2006 ◽  
Vol 95 (2) ◽  
pp. 414-420 ◽  
Author(s):  
Leigh M. Riby ◽  
Hazel McMurtrie ◽  
Jonathan Smallwood ◽  
Carrie Ballantyne ◽  
Andrew Meikle ◽  
...  
Keyword(s):  
Older Adults ◽  
Cognitive Load ◽  
Semantic Memory ◽  
Memory Retrieval ◽  
Repeated Measures ◽  
Task Difficulty ◽  
Enhancement Effect ◽  
Double Blind ◽  
Associate Learning ◽  
Glucose Ingestion

The ingestion of a glucose-containing drink has been shown to improve cognitive performance, particularly memory functioning. However, it remains unclear as to the extent to which task domain and task difficulty moderate the glucose enhancement effect. The aim of this research was to determine whether boosts in performance are restricted to particular classes of memory (episodic v. semantic) or to tasks of considerable cognitive load. A repeated measures (25g glucose v saccharin), counterbalanced, double-blind design was used with younger and older adults. Participants performed a battery of episodic (e.g. paired associate learning) and semantic memory (e.g. category verification) tasks under low and high cognitive load. Electrophysiological measures (heart rate and galvanic skin response) of arousal and mental effort were also gathered. The results indicated that whilst glucose appeared to aid episodic remembering, cognitive load did not exaggerate the facilitative effect. For semantic memory, there was little evidence to suggest that glucose can boost semantic memory retrieval even when the load was manipulated. One exception was that glucose facilitated performance during the difficult category fluency task. Regardless, the present findings are consistent with the domain-specific account in which glucose acts primarily on the hippocampal region, which is known to support episodic memory. The possible contribution of the hippocampus in semantic memory processing is also discussed.

scholarly journals The convergence and divergence of episodic and semantic functions across lateral parietal cortex

2020 ◽  
Author(s):  
Gina F. Humphreys ◽  
JeYoung Jung ◽  
Matthew A. Lambon Ralph
Keyword(s):  
White Matter ◽  
Semantic Memory ◽  
Parietal Cortex ◽  
Memory Retrieval ◽  
Task Difficulty ◽  
Structural Connectivity ◽  
Angular Gyrus ◽  
Episodic Retrieval ◽  
Semantic Retrieval ◽  
White Matter Connectivity

AbstractSeveral decades of neuropsychological and neuroimaging research have highlighted the importance of lateral parietal cortex (LPC) across a myriad of cognitive domains. Yet, despite the prominence of this region the underlying function of LPC remains unclear. Two domains that have placed particular emphasis on LPC involvement are semantic memory and episodic memory retrieval. From each domain, sophisticated models have been proposed as to the underlying function, as well as the more domain-general that LPC is engaged by any form of internally-directed cognition (episodic and semantic retrieval both being examples if this process). Here we directly address these alternatives using a combination of fMRI and DTI white-matter connectivity data. The results show that ventral LPC (angular gyrus) was positively engaged during episodic retrieval but disengaged during semantic memory retrieval. In addition, the level of activity negatively varied with task difficulty in the semantic task whereas episodic activation was independent of difficulty. In contrast, dorsal LPC (intraparietal sulcus) showed domain general activation that was positively correlated with task difficulty. In terms of structural connectivity, a dorsal-ventral and anterior-posterior gradient of connectivity was found to different processing networks (e.g., mid-angular gyrus (AG) connected with episodic retrieval). We propose a unifying model in which LPC as a whole might share a common underlying function (e.g., multimodal buffering) and variations across subregions arise due to differences in the underlying white matter connectivity.

scholarly journals Curcumin and cognition: a randomised, placebo-controlled, double-blind study of community-dwelling older adults

2016 ◽  
Vol 115 (12) ◽  
pp. 2106-2113 ◽  
Author(s):  
Stephanie R. Rainey-Smith ◽  
Belinda M. Brown ◽  
Hamid R. Sohrabi ◽  
Tejal Shah ◽  
Kathryn G. Goozee ◽  
...  
Keyword(s):  
Older Adults ◽  
Treatment Group ◽  
Repeated Measures ◽  
Community Dwelling ◽  
Blind Study ◽  
Double Blind Study ◽  
Cognitive Measures ◽  
Double Blind ◽  
Time Treatment ◽  
Community Dwelling Older Adults

AbstractCurcumin therapy in animals has produced positive cognitive and behavioural outcomes; results of human trials, however, have been inconsistent. In this study, we report the results of a 12-month, randomised, placebo-controlled, double-blind study that investigated the ability of a curcumin formulation to prevent cognitive decline in a population of community-dwelling older adults. Individuals (n 96) ingested either placebo or 1500 mg/d BiocurcumaxTM for 12 months. A battery of clinical and cognitive measures was administered at baseline and at the 6-month and 12-month follow-up assessments. A significant time×treatment group interaction was observed for the Montreal Cognitive Assessment (repeated-measures analysis; time×treatment; F=3·85, P<0·05). Subsequent analysis revealed that this association was driven by a decline in function of the placebo group at 6 months that was not observed in the curcumin treatment group. No differences were observed between the groups for all other clinical and cognitive measures. Our findings suggest that further longitudinal assessment is required to investigate changes in cognitive outcome measures, ideally in conjunction with biological markers of neurodegeneration.

Effect of Supplementation of a Whey Peptide Rich in β-Lactolin on Cognitive Performance in Healthy Adults: Randomized, Double-Blind, Placebo-Controlled Study

2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Tatsuhiro Ayabe ◽  
Masahiro Kita ◽  
Kuniaki Obara ◽  
Sumio Kondo ◽  
Satoshi Umeda ◽  
...  
Keyword(s):  
Older Adults ◽  
Placebo Group ◽  
Cognitive Decline ◽  
Cognitive Functions ◽  
Memory Retrieval ◽  
Verbal Fluency ◽  
Peptide Group ◽  
Double Blind ◽  
Double Blind Placebo ◽  
Fluency Test

IntroductionWith rapid increase of aging worldwide, the number of people suffering from cognitive decline and dementia has been rapidly increasing. Numerous epidemiological and clinical studies have shown that consumption of dairy products have beneficial effects on cognitive decline and dementia in elderly. Our previous demonstration using pharmacologically-induced amnesia model mice identified tryptophan-tyrosine-related peptides, especially glycine-threonine-tryptophan-tyrosine (GTWY) of lactotetrapeptide, b-lactolin, as responsible agents improving cognitive decline in whey digestions, and we have originally developed GTWY-rich whey peptide by a specific enzymatic digestion. However, the effect of GTWY-rich whey peptide on cognitive functions in human has not been investigated. The present study is the first clinical trial evaluating the effects of GTWY-rich whey peptide on cognitive functions in a randomized, double-blind, placebo-controlled design.MethodsHealthy middle to older adults, aged from 45 to 64 years, with a self-awareness of cognitive decline were recruited. 101 eligible subjects received either whey peptide tablets containing 1 g of the GTWY-rich whey peptide per day, which included 1.6 mg of GTWY, (N = 50) or placebo containing the same amount of maltodextrin (N = 51) for 12 weeks. Changes of cognitive functions from 0 week of the intervention were assessed using neuropsychological tests assessing memory functions (word recall, story recall and verbal fluency test) and attention and executive functions (stroop test, digit span, and paced auditory serial addition test) at 6 and 12 weeks.ResultsThe change of verbal fluency test (VFT) score evaluating long-term memory retrieval at 12 weeks in whey peptide group tended to be higher than that in placebo group. Subgroup analysis showed that in the subjects with high-level of subjective fatigue measured by visual-analog scale, the changes of VFT, stroop test evaluating inhibition of executive functions and subjective memory function test at 6 weeks in whey peptide group were significantly higher than those in placebo group. The change of VFT score was also significantly higher in subjects with high fatigue measured by profile of mood status.Discussion and ConclusionsThe present study suggests that consumption of GTWY-rich whey peptide improve cognitive functions, especially memory retrieval and executive function, in healthy middle to older adults, with high subjective fatigue. It is also suggested that prefrontal cortex functions, especially dorsolateral prefrontal cortex is associated with the effects of the whey peptide. Consumptions of 1 g GTWY-rich whey peptide in daily life are safe and easy, which might be a practical approach to support cognitive function.

scholarly journals Influence of Aging on the Neural Correlates of Autobiographical, Episodic, and Semantic Memory Retrieval

2011 ◽  
Vol 23 (12) ◽  
pp. 4150-4163 ◽  
Author(s):  
Marie St-Laurent ◽  
Hervé Abdi ◽  
Hana Burianová ◽  
Cheryl L. Grady
Keyword(s):  
Older Adults ◽  
Episodic Memory ◽  
Semantic Memory ◽  
Memory Retrieval ◽  
Memory Task ◽  
Neural Correlates ◽  
Partial Least Square ◽  
Least Square ◽  
Younger Adults ◽  
Age Related

We used fMRI to assess the neural correlates of autobiographical, semantic, and episodic memory retrieval in healthy young and older adults. Participants were tested with an event-related paradigm in which retrieval demand was the only factor varying between trials. A spatio-temporal partial least square analysis was conducted to identify the main patterns of activity characterizing the groups across conditions. We identified brain regions activated by all three memory conditions relative to a control condition. This pattern was expressed equally in both age groups and replicated previous findings obtained in a separate group of younger adults. We also identified regions whose activity differentiated among the different memory conditions. These patterns of differentiation were expressed less strongly in the older adults than in the young adults, a finding that was further confirmed by a barycentric discriminant analysis. This analysis showed an age-related dedifferentiation in autobiographical and episodic memory tasks but not in the semantic memory task or the control condition. These findings suggest that the activation of a common memory retrieval network is maintained with age, whereas the specific aspects of brain activity that differ with memory content are more vulnerable and less selectively engaged in older adults. Our results provide a potential neural mechanism for the well-known age differences in episodic/autobiographical memory, and preserved semantic memory, observed when older adults are compared with younger adults.

Reliability of center of pressure measures of postural stability in healthy older adults: Effects of postural task difficulty and cognitive load

2011 ◽  
Vol 33 (4) ◽  
pp. 651-655 ◽  
Author(s):  
Mojgan Moghadam ◽  
Hassan Ashayeri ◽  
Mahyar Salavati ◽  
Javad Sarafzadeh ◽  
Keyvan Davatgaran Taghipoor ◽  
...  
Keyword(s):  
Older Adults ◽  
Cognitive Load ◽  
Postural Stability ◽  
Task Difficulty ◽  
Center Of Pressure ◽  
Healthy Older Adults ◽  
Postural Task

Normalization of mediotemporal and prefrontal activity, and mediotemporal-striatal connectivity, may underlie antipsychotic effects of cannabidiol in psychosis

2020 ◽  
pp. 1-11 ◽  
Author(s):  
Aisling O'Neill ◽  
Robin Wilson ◽  
Grace Blest-Hopley ◽  
Luciano Annibale ◽  
Marco Colizzi ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Repeated Measures ◽  
Block Design ◽  
Study Drug ◽  
Learning Task ◽  
Blood Oxygen Level Dependent ◽  
Antipsychotic Treatment ◽  
Blood Oxygen Level ◽  
Double Blind ◽  
Associate Learning

Abstract Background Recent evidence suggests that cannabidiol (CBD), a non-intoxicating ingredient present in cannabis extract, has an antipsychotic effect in people with established psychosis. However, the effect of CBD on the neurocognitive mechanisms underlying psychosis is unknown. Methods Patients with established psychosis on standard antipsychotic treatment were studied on separate days at least one week apart, to investigate the effects of a single dose of orally administered CBD (600 mg) compared to a matched placebo (PLB), using a double-blind, randomized, PLB-controlled, repeated-measures, within-subject cross-over design. Three hours after taking the study drug participants were scanned using a block design functional magnetic resonance imaging (fMRI) paradigm, while performing a verbal paired associate learning task. Fifteen psychosis patients completed both study days, 13 completed both scanning sessions. Nineteen healthy controls (HC) were also scanned using the same fMRI paradigm under identical conditions, but without any drug administration. Effects of CBD on brain activation measured using the blood oxygen level-dependent hemodynamic response fMRI signal were studied in the mediotemporal, prefrontal, and striatal regions of interest. Results Compared to HC, psychosis patients under PLB had altered prefrontal activation during verbal encoding, as well as altered mediotemporal and prefrontal activation and greater mediotemporal-striatal functional connectivity during verbal recall. CBD attenuated dysfunction in these regions such that activation under its influence was intermediate between the PLB condition and HC. CBD also attenuated hippocampal-striatal functional connectivity and caused trend-level symptom reduction in psychosis patients. Conclusions This suggests that normalization of mediotemporal and prefrontal dysfunction and mediotemporal-striatal functional connectivity may underlie the antipsychotic effects of CBD.

scholarly journals Functional connectivity of the anterior and posterior hippocampus: differential effects of glucose in younger and older adults

2018 ◽  
Author(s):  
Riccarda Peters ◽  
David J. White ◽  
Brian R. Cornwell ◽  
Andrew Scholey
Keyword(s):  
Older Adults ◽  
Functional Connectivity ◽  
Resting State ◽  
Cognitive Testing ◽  
Human Cognition ◽  
Glucose Regulation ◽  
Resting State Functional Connectivity ◽  
Double Blind ◽  
Navigation Task ◽  
Glucose Ingestion

Abstract:The hippocampus features structurally and functionally distinct anterior and posterior segments. Relatively few studies have examined how these change during aging or in response to pharmacological interventions. Alterations in hippocampal connectivity and changes in glucose regulation have each been associated with cognitive decline in aging. A distinct line of research suggests that administration of glucose can lead to a transient improvement in hippocampus-dependent memory.Here we probe age, glucose and human cognition with a special emphasis on resting state functional connectivity (rsFC) of the hippocampus along its longitudinal axis to the rest of the brain. Using a randomized, placebo-controlled, double-blind, crossover design thirty-two healthy adults (16 young and 16 older) ingested a drink containing 25g glucose or placebo across two counterbalanced sessions. They then underwent resting state functional magnetic resonance imaging and cognitive testing. There was a clear dissociation in the effects of glucose by age. In older participants rsFC between posterior hippocampus (pHPC) and medial prefrontal cortex (mPFC) increased after glucose ingestion, whereas in younger participants connectivity decreased. Magnitude change in rsFC from pHPC to mPFC was correlated with individual glucose regulation and gains in performance on a spatial navigation task. Our results demonstrate that glucose administration can attenuate cognitive performance deficits in older adults with impaired glucose regulation and suggest that increases in pHPC-mPFC rsFC are beneficial for navigation task performance in older participants. This study is the first to demonstrate the selective modulation of pHPC connectivity in the acute setting.

Cognitive Load Affects Speech Motor Performance Differently in Older and Younger Adults

2019 ◽  
Vol 62 (5) ◽  
pp. 1258-1277 ◽  
Author(s):  
Megan K. MacPherson
Keyword(s):  
Older Adults ◽  
Cognitive Load ◽  
Motor Performance ◽  
Age Groups ◽  
Incongruent Condition ◽  
Sentence Production ◽  
Movement Duration ◽  
Production Task ◽  
Younger Adults ◽  
Speech Motor

PurposeThe aim of this study was to determine the impact of cognitive load imposed by a speech production task on the speech motor performance of healthy older and younger adults. Response inhibition, selective attention, and working memory were the primary cognitive processes of interest.MethodTwelve healthy older and 12 healthy younger adults produced multiple repetitions of 4 sentences containing an embedded Stroop task in 2 cognitive load conditions: congruent and incongruent. The incongruent condition, which required participants to suppress orthographic information to say the font colors in which color words were written, represented an increase in cognitive load relative to the congruent condition in which word text and font color matched. Kinematic measures of articulatory coordination variability and movement duration as well as a behavioral measure of sentence production accuracy were compared between groups and conditions and across 3 sentence segments (pre-, during-, and post-Stroop).ResultsIncreased cognitive load in the incongruent condition was associated with increased articulatory coordination variability and movement duration, compared to the congruent Stroop condition, for both age groups. Overall, the effect of increased cognitive load was greater for older adults than younger adults and was greatest in the portion of the sentence in which cognitive load was manipulated (during-Stroop), followed by the pre-Stroop segment. Sentence production accuracy was reduced for older adults in the incongruent condition.ConclusionsIncreased cognitive load involving response inhibition, selective attention, and working memory processes within a speech production task disrupted both the stability and timing with which speech was produced by both age groups. Older adults' speech motor performance may have been more affected due to age-related changes in cognitive and motoric functions that result in altered motor cognition.

Effects of Aging on the Subcortical Encoding of Stop Consonants

2020 ◽  
Vol 29 (3) ◽  
pp. 391-403
Author(s):  
Dania Rishiq ◽  
Ashley Harkrider ◽  
Cary Springer ◽  
Mark Hedrick
Keyword(s):  
Older Adults ◽  
Repeated Measures ◽  
Mixed Model ◽  
Auditory Brainstem ◽  
Auditory Brainstem Responses ◽  
Aging Effects ◽  
Formant Frequency ◽  
Place Of Articulation ◽  
Second Formant ◽  
Effects Of Aging

Purpose The main purpose of this study was to evaluate aging effects on the predominantly subcortical (brainstem) encoding of the second-formant frequency transition, an essential acoustic cue for perceiving place of articulation. Method Synthetic consonant–vowel syllables varying in second-formant onset frequency (i.e., /ba/, /da/, and /ga/ stimuli) were used to elicit speech-evoked auditory brainstem responses (speech-ABRs) in 16 young adults ( M age = 21 years) and 11 older adults ( M age = 59 years). Repeated-measures mixed-model analyses of variance were performed on the latencies and amplitudes of the speech-ABR peaks. Fixed factors were phoneme (repeated measures on three levels: /b/ vs. /d/ vs. /g/) and age (two levels: young vs. older). Results Speech-ABR differences were observed between the two groups (young vs. older adults). Specifically, older listeners showed generalized amplitude reductions for onset and major peaks. Significant Phoneme × Group interactions were not observed. Conclusions Results showed aging effects in speech-ABR amplitudes that may reflect diminished subcortical encoding of consonants in older listeners. These aging effects were not phoneme dependent as observed using the statistical methods of this study.

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