Overview of age-related changes in psychomotor and cognitive functions in a prosimian primate, the gray mouse lemur (Microcebus murinus): Recent advances in risk factors and antiaging interventions

Aging is not homogeneous in humans and the determinants leading to differences between subjects are not fully understood. Impaired glucose homeostasis is a major risk factor for cognitive decline in middle-aged humans, pointing at the existence of early markers of unhealthy aging. The gray mouse lemur (Microcebus murinus), a small lemuriform Malagasy primate, shows relatively slow aging with decreased psychomotor capacities at middle-age (around 5-year old). In some cases (∼10%), it spontaneously leads to pathological aging. In this case, some age-related deficits, such as severe cognitive decline, brain atrophy, amyloidosis, and glucoregulatory imbalance are congruent with what is observed in humans. In the present review, we inventory the changes occurring in psychomotor and cognitive functions during healthy and pathological aging in mouse lemur. It includes a summary of the cerebral, metabolic, and cellular alterations that occur during aging and their relation to cognitive decline. As nutrition is one of the major nonpharmacological antiaging strategies with major potential effects on cognitive performances, we also discuss its role in brain functions and cognitive decline in this species. We show that the overall approach of aging studies in the gray mouse lemur offers promising ways of investigation for understanding, prevention, and treatments of pathological aging in humans.

Moderators of the Impact of (Poly)Phenols Interventions on Psychomotor Functions and BDNF: Insights from Subgroup Analysis and Meta-Regression

BACKGROUND

Recent anti-aging interventions have shown contradictory impacts of (poly)phenols regarding the prevention of cognitive decline and maintenance of brain function. These discrepancies have been linked to between-study differences in supplementation protocols. This subgroup analysis and meta-regression aimed to (i) examine differential effects of moderator variables related to participant characteristics and supplementation protocols and (ii) identify practical recommendations to design effective (poly)phenol supplementation protocols for future anti-aging interventions.

METHODS

Multiple electronic databases (Web of Science; PubMed) searched for relevant intervention published from inception to July 2019. Using the PICOS criteria, a total of 4303 records were screened. Only high-quality studies (n = 15) were included in the final analyses. Random-effects meta-analysis was used, and we calculated standard differences in means (SDM), effect size (ES), and 95% confidence intervals (CI) for two sufficiently comparable items (i.e., psychomotor function and brain-derived neurotrophic factor (BDNF)). When significant heterogeneity was computed (I² > 50%), a subgroup and meta-regression analysis were performed to examine the moderation effects of participant characteristics and supplementation protocols.

RESULTS

The reviewed studies support the beneficial effect of (poly)phenols-rich supplementation on psychomotor functions (ES = -0.677, p = 0.001) and brain plasticity (ES = 1.168, p = 0.028). Subgroup analysis revealed higher beneficial impacts of (poly)phenols (i) in younger populations compared to older (SDM = -0.89 vs. -0.47 for psychomotor performance, and 2.41 vs. 0.07 for BDNF, respectively), (ii) following an acute compared to chronic supplementation (SDM = -1.02 vs. -0.43 for psychomotor performance), and (iii) using a phenolic compound with medium compared to low bioavailability rates (SDM = -0.76 vs. -0.68 for psychomotor performance and 3.57 vs. 0.07 for DBNF, respectively). Meta-regressions revealed greater improvement in BDNF levels with lower percentages of female participants (Q = 40.15, df = 6, p < 0.001) and a skewed scatter plot toward a greater impact using higher (poly)phenols doses.

CONCLUSION

This review suggests that age group, gender, the used phenolic compounds, their human bioavailability rate, and the supplementation dose as the primary moderator variables relating to the beneficial effects of (poly)phenol consumption on cognitive and brain function in humans. Therefore, it seems more advantageous to start anti-aging (poly)phenol interventions in adults earlier in life using medium (≈500 mg) to high doses (≈1000 mg) of phenolic compounds, with at least medium bioavailability rate (≥9%).

Impact of At Least 2 Years of Synthetic Cannabinoid Use on Cognitive and Psychomotor Functions Among Treatment-Seeking Male Outpatients

Introduction: Synthetic cannabinoid (SC) use, an important public health problem, is becoming increasingly widespread and leads to many medical and psychiatric problems. This study aimed to evaluate the impact of SC use on cognitive and psychomotor functions of patients. Materials and Methods: The participants (30 outpatients with SC use disorder and 33 healthy controls) were administered the Montreal Cognitive Assessment (MOCA) test, the Edinburgh Handedness Inventory (EHI), the Finger-Tapping Test (FTT), and the Adult Memory and Information Processing Battery-B form (AMIPB-B). Results: The SC users scored lower in AMIPB-B, MOCA. and FTT compared to the healthy controls. Conclusion: These findings suggest that SC might impair both cognitive and psychomotor functions. Therefore, outpatients with SC use disorder should be carefully evaluated for cognitive and psychomotor functions since neurological examinations and interventions may also be required in treatment programs for these cases.

It's all in the mime: Actions speak louder than words when teaching the cranial nerves

Cranial nerve (CN) knowledge is essential for students in health professions. Gestures and body movements (e.g., mime) have been shown to improve cognition and satisfaction with anatomy teaching. The aim of this pilot study was to compare the effectiveness of didactic lecturing with that of miming lecturing for student learning of the CNs. The research design involved exposure of the same group of students to didactic followed by miming lecturing of CNs. The effectiveness of each lecturing strategy was measured via pre- and post-testing. Student perceptions of these strategies were measured by a survey. As an example of miming, gestures for CN VII included funny faces for muscles of facial expression, kangaroo vocalization for taste, spitting action for saliva production, and crying for lacrimal gland production. Accounting for extra duration of the miming lecture, it was shown that pre- to post-test improvement was higher for the miming presentation than for the didactic (0.47 ± 0.03 marks/minute versus 0.33 ± 0.03, n = 39, P < 0.005). Students perceived that the miming lecture was more interactive, engaging, effective, and motivating to attend (mean on five-point Likert scale: 4.62, 4.64, 4.56, 4.31, respectively) than the didactic lecture. In the final examination, performance was better (P < 0.001, n = 39) on the CN than on the non-CN questions-particularly for students scoring ≤60%. While mediating factors need elucidation (e.g., learning due to repetition of content), this study's findings support the theory that gestures and body movements help learners to acquire anatomical knowledge.

The recovery time of sevoflurane and desflurane and the effects of anesthesia on mental and psychomotor functions and pain

Background:

Inhalation anesthetics have many advantages for outpatient general anesthesia, such as minimal postoperative side-effects and rapid and full recovery. The aim of this randomized study was to compare the postoperative recovery time of sevoflurane and desflurane and to observe the effects of anesthesia on mental, psychomotor and cognitive functions and pain in outpatients undergoing arthroscopic surgery.

Patients and Methods:

This study included 40 American Society of Anesthesiologists I-II patients who were divided into two groups via sealed envelopes. For maintenance of anesthesia, a mixture of 66% N₂O and 33% O₂ and 4–7% desflurane was used in Group D, and a mixture of 66% N₂O and 33% O₂ and 1–2.5% sevoflurane was used in Group S. The modified Aldrete score (MAS) was evaluated postoperatively at time points determined previously. An MAS of 8 or higher was considered to indicate alertness. Mental and psychomotor functions of the patients were evaluated using the short cognitive examination (SCE), and postoperative pain levels were evaluated using the visual analogue scale (VAS).

Results:

There was no difference between the groups in terms of demographic data (P > 0.05). The mean time to reach MAS 8, eye-opening, and orientation were higher in Group S as compared to Group D (P < 0.01). The mean MAS initially and at 5 and 10 min was higher in Group D as compared to Group S (P < 0.001). The mean SCE at 5 and 15 min was higher in Group D as compared to Group S (P < 0.01). There was no significant difference between the groups in terms of VAS scores (P > 0.05).

Conclusion:

It has been determined that desflurane provided better quality and more rapid recovery than sevoflurane, and the return of cognitive functions in the early postoperative period was faster. In conclusion, both agents can apparently be used safely in outpatient anesthetic procedures.