Effects of the Acute and Chronic Administration of Cannabidiol on Cognition in Humans and Animals: A Systematic Review.

Introduction: The effects of cannabidiol (CBD) on cognition has been investigated in recent years to determine the therapeutic potential of this cannabinoid for a broad gamut of medical conditions, including neuropsychiatric disorders. The aim of the present study was to perform a systematic review of studies that analyzed the effects of the acute and chronic administration of CBD on cognition in humans and animals both to assess the cognitive safety of CBD and to determine a beneficial potential of CBD on cognition. Methods: The PubMed, Web of Science, PsycINFO, and Scopus databases were searched in December of 2022 for relevant articles using the following combinations of keywords: ("cannabidiol" OR "CBD") AND ("cognition" OR "processing cognitive" OR "memory" OR "language" OR "attention" OR "executive function" OR "social cognition" OR "perceptual motor ability" OR "processing speed"). Results: Fifty-nine articles were included in the present review (36 preclinical and 23 clinical trials). CBD seems not to have any negative effect on cognitive processing in rats. The clinical trials confirmed these findings in humans. One study found that repeated dosing with CBD may improve cognitive in people who use cannabis heavily but not individuals with neuropsychiatric disorders. Considering the context of neuropsychiatric disorders in animal models, CBD seems to reverse the harm caused by the experimental paradigms, such that the performance of these animals becomes similar to that of control animals. Conclusions: The results demonstrate that the chronic and acute administration of CBD seems not to impair cognition in humans without neuropsychiatric disorders. In addition, preclinical studies report promising results regarding the effects of CBD on the cognitive processing of animals. Future double-blind, placebo-controlled, randomized clinical trials with larger, less selective samples, with standardized tests, and using different doses of CBD in outpatients are of particular interest to elucidate the cognitive effects of CBD.

Are facial emotion recognition tasks adequate for assessing social cognition in older people? A review of the literature.

OBJECTIVE: Facial emotion recognition (FER) is a component of social cognition and important to interpersonal relations. Therefore, tasks have been developed to assess this skill in different population. Regarding older people, even healthy individuals have a poorer performance compared to rate of correct answers commonly used to assess such tasks. Perform a systematic review to analyze studies addressing the performance of healthy older adults on FER tasks compared to the 70% correct response rate commonly used for the creation of stimulus banks. MATERIAL AND METHODS: Searches were conducted up to May 2019 in the Pubmed, PsycInfo, Web of Science, and Scopus databases using the keywords ("faces" OR "facial") AND ("recognition" OR "expression" OR "emotional") AND ("elderly" OR "older adults"). RESULTS: Twenty-seven articles were included in the present review. In 16 studies (59.2%), older people had correct response rates on FER lower than 70% on at least one of the emotions evaluated. Among the studies that evaluated each emotion specifically, 62.5% found correct response rates lower than 70% for the emotion fear, 50% for surprise, 50% for sadness, 37.5% for anger, 21.4% for disgust, and 5.9% for happiness. Moreover, the studies that evaluated the level of intensity of the emotions demonstrated a lower rate of correct responses when the intensity of the facial expression was low. CONCLUSION: That studies employ methods and facial stimuli that may not be adequate for measuring this skill in older people. Thus, it is important to create adequate tasks for assessing the skill in this population.

Acute effects of oxytocin in music performance anxiety: a crossover, randomized, placebo-controlled trial.

RATIONALE: Individuals with music performance anxiety (MPA) present physical, behavioral, and cognitive manifestations of anxiety, in addition to information processing deficits, especially in facial emotion recognition (FER). OBJECTIVES: To assess the effects of a single dose of intranasal oxytocin (24 IU) on FER in a sample of musicians with high and low MPA (primary outcome), as well as indicators of mood/anxiety and self-assessed performance (secondary outcomes). METHODS: Crossover, randomized, double-blind, placebo-controlled trial involving 43 male musicians with different levels of MPA. Participants completed a static facial emotion recognition task and self-rated mood and performance scales. Data were analyzed using ANOVA 2 × 0 for crossover trials and the Omnibus test (measure of separability between intervention and carryover effects). RESULTS: Only musicians with high MPA treated with oxytocin had a higher accuracy in the recognition of happiness (p < 0.03; d > 0.72). No effects of oxytocin were found on mood indicators or on self-perceived performance, regardless of MPA level. CONCLUSIONS: The results indicate possible benefits of the acute treatment with oxytocin in MPA, which may improve the management of this common and disabling condition that affects professional musicians. The appropriate perception of positive feedback may increase confidence and feelings of social acceptance, reducing symptoms associated with the condition. The lack of effects on mood/anxiety and cognition may be explained by the context-dependent characteristic of the effects of oxytocin, since the experiment did not represent an actual situation of social threat. TRIAL REGISTRATION: Brazilian Clinical Trials Registry (Registro Brasileiro de Ensaios Clínicos): No. RBR-9cph2q.

Frailty and cognitive decline.

Frailty and cognitive impairment are among the 2 most common geriatric syndromes. Their presence poses major risks to the elderly including greater disability, reduced quality of life, and higher morbi-mortality. Recent evidence suggest that frailty can be a risk factor for incident dementia. The opposite is also true since subjects with Alzheimer's disease and other dementia also present with more severe frailty measures. The mechanisms for the association between frailty and cognitive impairment is not clear, but possibly involves abnormalities in biological processes related to aging. Here, we will review the current evidence of the association between frailty and cognitive impairment. We will also review the possible biological mechanistic links between the 2 conditions. Finally, we will address potential therapeutic targets and interventions that can mitigate both conditions.

Diagnostic criteria and prevalence of mild cognitive impairment in older adults living in the community: a systematic review and meta-analysis

Abstract Background Mild Cognitive Impairment (MCI) is a disorder in which the patient presents a cognitive decline, but without negative impact on the activities of daily living. Objective To carry out a systematic review of published studies that analyzed the prevalence of Mild Cognitive Impairment (MCI) in older adults living in the community, and the criteria used for the diagnosis of this disorder. Methods A search was carried out in May 2017 using the descriptors: "epidemiology" or "prevalence", "mild cognitive impairment", and "community" in the PubMed, PsycInfo, SciELO, Web of Science, and Scopus databases. Two independent researchers extracted and documented the data. We used a random effect model to calculate pooled prevalence of MCI for overall studies and for each subgroup divided by diagnostic criteria. Results We found initially 1996 articles, and we selected 35 studies. The prevalence of MCI in the selected studies ranged from 0.5% to 41.8%. The overall pooled prevalence of MCI was 17.3% (CI 95%, 13.8-20.8), with significant heterogeneity between estimates (I2 = 99.6%). Discussion The standardization of the diagnostic criteria for MCI, as well as the tests used in the cognitive evaluation, could allow the comparison between the studies and would be an important step in the researches of this area.

Facial Recognition of Happiness Is Impaired in Musicians with High Music Performance Anxiety.

INTRODUCTION: Music performance anxiety (MPA) can be defined as a lasting and intense apprehension connected with musical performance in public. Studies suggest that MPA can be regarded as a subtype of social anxiety. Since individuals with social anxiety have deficits in the recognition of facial emotion, we hypothesized that musicians with high levels of MPA would share similar impairments. OBJECTIVE: The aim of this study was to compare parameters of facial emotion recognition (FER) between musicians with high and low MPA. METHODS: 150 amateur and professional musicians with different musical backgrounds were assessed in respect to their level of MPA and completed a dynamic FER task. The outcomes investigated were accuracy, response time, emotional intensity, and response bias. RESULTS: Musicians with high MPA were less accurate in the recognition of happiness (p = 0.04; d = 0.34), had increased response bias toward fear (p = 0.03), and increased response time to facial emotions as a whole (p = 0.02; d = 0.39). CONCLUSION: Musicians with high MPA displayed FER deficits that were independent of general anxiety levels and possibly of general cognitive capacity. These deficits may favor the maintenance and exacerbation of experiences of anxiety during public performance, since cues of approval, satisfaction, and encouragement are not adequately recognized.

Factors associated with happiness in the elderly persons living in the community.

OBJECTIVE: The aim of the present study was to evaluate factors associated with happiness in a sample of Brazilian older adults. METHODS: A study was conducted with 263 elderly people in the area of coverage of a family health unit located in the state of São Paulo, Brazil. The Subjective Happiness Scale was used to measure happiness, the final score of which determined one of three outcomes: not happy, intermediate, and happy. Disability, sociodemographic characteristics, and psychological, cognitive, and physical factors were considered for the multinomial logistic regression analysis. RESULTS: Statistically significant differences were found among the three groups regarding satisfaction with life, disability, social phobia, anxiety, depression, and frailty (p≤0.05). In the multinomial regression analysis, being "not happy" was significantly associated with satisfaction with life (RRR: 0.53), depression (RRR: 1.46), social phobia (RRR: 1.24), and age (RRR: 1.06). CONCLUSION: The present findings indicate that psychological factors and age influence the levels of happiness in older adults living in the community. Furthermore, better screening, diagnosis, and treatment of mental health disorders could increase the feeling of happiness among older adults.

Can anxiety increase tremors in patients with Parkinson's disease? An experimental model

Abstract Background Among non-motor symptoms of Parkinson's disease (PD), anxiety occurs in up to 67% of patients. Clinically, PD patients report worsening of tremors in anxiogenic situations. Objective The aim of this study was to evaluate the association between motor symptoms and anxiety in PD patients and compare their performances with those of healthy volunteers. Methods Fifteen volunteers with PD and 15 healthy volunteers without clinically significant psychiatric disorders were evaluated. Both groups were subjected to a simulated public speaking test (SPST). The following parameters were measured: visual analog mood scale (VAMS), items related to tremors of UPDRS, bradykinesia tests, blood pressure, and heart rate. Results Results of repeated measures ANOVA indicated a significant effect on group × phase interaction (F3.7,105.6 = 2.56; p = 0.046) for VAMS anxiety factor. Regarding tremors, ANOVA indicated significant differences in group × phase interaction (F4.5,121 = 2.88; p = 0.021) and between the groups (F1,27 = 45.88, p < 0.001), with differences in the anticipatory phase, performance, and post-speech, compared with those in the baseline. There were no significant differences between the groups with regard to other factors of VAMS, physiological measurements, and bradykinesia. Discussion Worsening of tremors occurred during SPST, particularly in phases with higher anxiety scores.