The Effects of a Novel Non-catechol Dopamine Partial Agonist on Working Memory in the Aged Rhesus Monkey

Aged-related declines in cognition, especially working memory and executive function, begin in middle-age and these abilities are known to be mediated by the prefrontal cortex (PFC) and more specifically the dopamine (DA) system within the PFC. In both humans and monkeys, there is significant evidence that the PFC is the first cortical region to change with age and the PFC appears to be particularly vulnerable to age-related loss of dopamine (DA). Therefore, the DA system is a strong candidate for therapeutic intervention to slow or reverse age related declines in cognition. In the present study, we administered a novel selective, potent, non-catechol DA D1 R agonist PF-6294 (Pfizer, Inc.) to aged female rhesus monkeys and assessed their performance on two benchmark tasks of working memory – the Delayed Non-match to Sample Task (DNMS) and Delayed Recognition Span Task (DRST). The DNMS task was administered first with the standard 10 s delay and then with 5 min delays, with and without distractors. The DRST was administered each day with four trials with unique sequences and one trial of a repeated sequence to assess evidence learning and retention. Overall, there was no significant effect of drug on performance on any aspect of the DNMS task. In contrast, we demonstrated that a middle range dose of PF-6294 significantly increased memory span on the DRST on the first and last days of testing and by the last day of testing the increased memory span was driven by the performance on the repeated trials.

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The Effect of Working Memory Rehabilitation on Visual Memory and Memory Span

Elderly Health Journal ◽

10.18502/ehj.v6i2.5018 ◽

2020 ◽

Author(s):

Mansour Mahmoudi Aghdam ◽

Esmaeil Soleimani ◽

Ali Issa Zadegan

Keyword(s):

Working Memory ◽

Cognitive Decline ◽

Elderly People ◽

Cognitive Aging ◽

Visual Memory ◽

Memory Span ◽

Control Group ◽

Age Related ◽

Memory Rehabilitation ◽

The Mean

Introduction: Age-related cognitive decline or cognitive aging is largely the result of structural and functional decline in specific areas of the brain, but lifestyle also contributes to this cognitive decline. The aim of this study was to investigate the effect of working memory rehabilitation on visual memory and memory span in ageing. Methods: This was a quasi-experimental study with pretest-posttest design and a control group. The study population included all elderly people who lived in Bukan Nursing Home from April to July 2019 (N = 120). Among these individuals, 30 elderly people were selected by convenience sampling method and then randomly assigned to two experimental and control groups (two groups of 15 people). Kim Karad Visual Memory Test and Wechsler Memory Span Test were taken from the groups in pretest. The working memory rehabilitation was performed in 18 sessions (each sessions 60-minute) and after which the test was performed again. The data were analyzed by multivariate covariance test according to its assumptions. Results: The results showed that after the rehabilitation of working memory, in the experimental group, the mean of short, medium and long components of visual memory were 12.00, 10.8 and 12.33, respectively, and the direct and inverse of memory span were 11.66 and 9.66, respectively. In the control group, the average of short, medium and long components of visual memory is 7.00, 6.70 and 9.00, respectively, and direct and inverse of memory span is 8.33 and 6.46, respectively. The difference in the mean scores between the two groups in the components of visual memory and memory span after the intervention was significant (p < 0.001). Conclusion: The results showed that working memory rehabilitation can improve visual memory and memory span, and it is recommended that this rehabilitation method be used to improve the cognitive functions of the elderly.

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Delayed recognition memory span in HIV-1 infection

Journal of the International Neuropsychological Society ◽

10.1017/s1355617700000710 ◽

1995 ◽

Vol 1 (6) ◽

pp. 575-580 ◽

Cited By ~ 21

Author(s):

Eileen M. Martin ◽

David L. Pitrak ◽

Kenneth J. Pursell ◽

Kathleen M. Mullane ◽

Richard M. Novak

Keyword(s):

Substance Abuse ◽

Working Memory ◽

Substance Abusers ◽

Memory Span ◽

Memory Function ◽

Memory Task ◽

Basal Ganglia Disease ◽

History Of ◽

Delayed Recognition ◽

Hiv Seropositive

AbstractWe administered a spatial version of the Delayed Recognition Span Test (DRST), a working memory task performed abnormally by patients with basal ganglia disease, to a group of 96 HIV-seropositive and 83 seronegative subjects with a high prevalence of substance abuse. For comparison purposes, we also administered the Symbol-Digit Modalities Test (SDMT) and the Trail Making Test (TMT), measures which detect HIV-related mental slowing efficiently in gay men but are nonspecifically impaired in subjects with a history of substance abuse. As predicted, scores on the TMT and the SDMT did not discriminate the groups, but HIV-seropositive subjects had significantly shorter spatial spans (p < .007) and DRST total scores (p < .005). These effects could not be attributed to differences in age, education, estimated intelligence, or psychological distress, because the groups were well matched on these variables. The DRST is a promising measure of HIV-related cognitive dysfunction in substance abusers, who are often nonspecifically impaired on psychomotor tasks. These preliminary data also indicate that working memory function should be studied further in HIV-seropositive subjects. (JINS, 1995, 1, 575–580.)

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Does predictive cueing of encoding stimulus duration modulate alpha power and facilitate visual working memory performance in younger and older adults?

10.31234/osf.io/3c27r ◽

2021 ◽

Author(s):

Sabrina Sghirripa ◽

Lynton Graetz ◽

Nigel Rogasch ◽

John Semmler ◽

Mitchell Goldsworthy

Keyword(s):

Older Adults ◽

Working Memory ◽

Visual Working Memory ◽

Memory Performance ◽

Age Groups ◽

Alpha Power ◽

Retention Period ◽

Match To Sample ◽

Age Related ◽

Oscillatory Power

Both selective attention and visual working memory (WM) performance are vulnerable to age related decline. Older adults perform worse on, and are less able to modulate oscillatory power in the alpha frequency range (8-12 Hz) than younger adults in WM tasks involving predictive cues about ‘where’ or ‘when’ a stimulus will be present. However, no study has investigated whether alpha power is modulated by cues predicting ‘how long’ an encoding duration will be. To test this, we recorded electroencephalography (EEG) while 24 younger (aged 18-33 years) and 23 older (aged 60-77 years) adults completed a modified delay match-to-sample task where participants were cued to the duration (either 0.1 s or 0.5 s) of an encoding stimulus consisting of 4 coloured squares. We found: (1) predictive cues increased WM capacity, but long encoding duration trials led to reduced WM capacity in both age groups, compared to short encoding duration trials; (2) no evidence for differences in preparatory alpha power between predictive and neutral cues for either short or long encoding durations, but preparatory alpha suppression was weaker in older adults; (3) retention period oscillatory power differed between short and long encoding duration trials, but these differences were no longer present when comparing the trial types from the onset of the encoding stimulus; and (4) oscillatory power in the preparatory and retention periods were not related to task performance. Our results suggest that preparatory alpha power is not modulated by predictive cues towards encoding duration during visual WM, however, reductions in alpha/beta oscillatory power during visual WM retention may be linked to the encoding stimulus, rather than a process specific to WM retention.

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Working Memory and Reading: A Life-span Perspective

International Journal of Behavioral Development ◽

10.1177/016502549401700107 ◽

1994 ◽

Vol 17 (1) ◽

pp. 109-124 ◽

Cited By ~ 126

Author(s):

Linda S. Siegel

Keyword(s):

Working Memory ◽

Reading Skills ◽

Short Term Memory ◽

Memory Span ◽

Memory Task ◽

Older Individuals ◽

Short Term ◽

Term Memory ◽

Age Related ◽

Rehearsal Strategies

The relationships among working memory, memory span, and reading skills were studied in 1266 individuals, aged 6-49. They were administered tests of word recognition, pseudoword decoding, reading comprehension, a working memory (listening span) task that required the simultaneous processing of syntax and the recall of linguistic information, and a short-term memory task that required the recall of rhyming or nonrhyming letters presented visually. The results indicated that there is a gradual growth in the development of working memory skills from ages 6 to 19 and a gradual decline after adolescence. The short-term memory task did not show a decline in performance among older individuals. On both of these memory tasks and at most of the age levels, individuals with a reading disability performed at significantly lower levels than individuals with normal reading skills. An important component of the development of reading skills appears to be memory for verbal information. Age-related declines in memory appear to be related to the processing demands of the task, which may affect the degree to which rehearsal strategies are possible within the task.

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EFFECTS OF BILINGUALISM ON INHIBITORY CONTROL AND WORKING MEMORY: A STUDY WITH EARLY AND LATE BILINGUALS

Gragoatá ◽

10.22409/gragoata.v20i38.33312 ◽

2015 ◽

Vol 20 (38) ◽

Cited By ~ 3

Author(s):

Rossana Kramer ◽

Mailce Borges Mota

Keyword(s):

Working Memory ◽

Inhibitory Control ◽

Executive Control ◽

Memory Span ◽

Dense Body ◽

Brazilian Portuguese ◽

Younger Adults ◽

Age Related ◽

Bilingual Group ◽

Late Bilinguals

A dense body of research shows that cognitive functions change with age. More recently, studies have provided evidence that bilingualism aids in offsetting age-related losses in executive function (Bialystok, Craik, Klein & Viswanathan, 2004; Salvatierra, 2010). The present study investigates the performances of early bilinguals (Brazilian Portuguese/Hunsrückisch), late bilinguals (Brazilian Portuguese/English), and monolinguals (Brazilian Portuguese) on executive control and working memory tasks. Participants (N = 104) performed an executive control task (Simon) and a working memory (Alpha Span) task. Statistical analyses showed significant age-related effects on executive functions: younger adults outperformed older adults in the tasks. Furthermore, early bilinguals presented more efficient inhibitory processes showing smaller Simon effect costs and higher working memory span than monolinguals. As for the late bilingual group, their performance on inhibitory control tasks was significantly faster than that of their peer monolingual group. Results suggest that bilingualism, regardless of the context and age of acquisition, has an effect on inhibitory control and working memory.

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