Sex Differences in Brain and Cognition in de novo Parkinson's Disease

Background and Objective: Brain atrophy and cognitive impairment in neurodegenerative diseases are influenced by sex. We aimed to investigate sex differences in brain atrophy and cognition in de novo Parkinson's disease (PD) patients.Methods: Clinical, neuropsychological and T1-weighted MRI data from 205 PD patients (127 males: 78 females) and 69 healthy controls (40 males: 29 females) were obtained from the PPMI dataset.Results: PD males had a greater motor and rapid eye movement sleep behavior disorder symptomatology than PD females. They also showed cortical thinning in postcentral and precentral regions, greater global cortical and subcortical atrophy and smaller volumes in thalamus, caudate, putamen, pallidum, hippocampus, and brainstem, compared with PD females. Healthy controls only showed reduced hippocampal volume in males compared to females. PD males performed worse than PD females in global cognition, immediate verbal recall, and mental processing speed. In both groups males performed worse than females in semantic verbal fluency and delayed verbal recall; as well as females performed worse than males in visuospatial function.Conclusions: Sex effect in brain and cognition is already evident in de novo PD not explained by age per se, being a relevant factor to consider in clinical and translational research in PD.

Intergenerational Education and Late-life Cognitive Decline among Latinos and Non-Hispanic Whites

Latinos face a growing burden of Alzheimer’s Disease and related dementia (ADRD). Although education has been established as a strong predictor of ADRD, evidence to date is primarily for non-Latino cohorts. Few studies have assessed the relationship between intergenerational education and one’s cognitive decline. Using the US Health and Retirement Study (N=20,860) we evaluated the joint effect of parental and own educational attainment on immediate and delayed verbal memory scores (range 0-10) from 1998 to 2016. The exposure was a 4-category variable based on parents’ (highest of mother’s or father’s) and participant’s own high school attainment: first-generation (parents’ education <12; own ≥12); multi-generation (both ≥12: REF); neither graduated high school (both <12) and parent(s) graduated high school but not respondent (parents ≥12; own <12). Linear mixed effects models with subject-specific random intercepts and random slopes were stratified by race/ethnicity and tested for a 3-way interaction term (exposure x Latino x time). Models controlled for age, sex, place of birth and retest effects. Baseline verbal memory scores did not differ for first-generation compared to multi-generation high school graduates. Verbal memory decline was faster for first- compared to multi-generation high school graduates among non-Hispanic whites (e.g., β=-0.04; 95% CI: -0.05, -0.03, delayed verbal recall); among Latinos, first and multi-generation high school graduates had similar rates of decline (e.g. β=0.00; 95% CI: -0.03, 0.04, delayed verbal recall; p<0.001 for three-way interaction). Our findings suggest social and economic policies that facilitate educational achievement, particularly for important population subgroups, may reduce ADRD risk.

Hands-on learning: The influence of hand gestures on children's recall of scientific information

<p>When people speak they typically also gesture. Gesture and speech form an integrated communication system, with speech conveying information in a rule-bound and sequential manner (i.e. one word follows the other in accordance with grammatical rules) while gesture conveys information holistically in a visuospatial representation. These gestural hand movements not only aid the process of speaking, but also convey important information to the listener. While observing gesture during learning can facilitate children’s understanding and remembering of novel and isolated information (e.g.(Cook, Duffy, & Fenn, 2013), observing gesture may also support children in recalling complex, discursive content. This thesis examined the role observing gesture may play in supporting children’s learning and recall of narrative, scientific content. The 7- to 9-year-old children, who participated in this program of research, learnt about the solar system either with or without accompanying gestures. Children’s recall was assessed via interviews, both at short delays (one day) and long delays (two weeks or seven months after learning). It was hypothesised that gesture would improve children’s recall by grounding the abstract scientific ideas in a physical representation, disambiguating novel terms, and providing an additional representation for children to process, store, and retrieve. In Study 1, the influence of observing gesture in supporting children’s learning and recall was examined in combination with adult initiated wh-questions. The study was also conducted in the presence of visual aids. Results indicated that observing gesture only had a limited effect on children’s recall in Study 1 (both independently and in combination with wh-questions), so Study 2 examined the role of observing gesture in the absence of additional visual and verbal supports. Children’s recall was assessed both the next day and seven months later. Study 3 then manipulated both the gesture children observed at learning and the gesture children performed during recall the next day (i.e. instructed, allowed or restricted from gesturing). Finally, Study 4 examined children’s recall of spatial terms across the three studies. The overarching results revealed that children who observed gesture during learning tended to report more spatial terms, but did not show improved recall of the facts and concepts taught. When children observed gesture they did, however, produce a greater rate of representational gestures during recall. In particular, children who observed gesture were more likely to mimic the gestures they had observed, and in doing so improve their verbal recall both within the same interview and across interviews. The instruction to produce gesture did not appear to be effective in augmenting the influence of children’s gesture production, but restricting children from gesturing was found to hinder recall. Observing gesture was only indirectly effective in supporting children’s recall. One possible explanation for this findings may be that children found it difficult to integrate the gestural and verbal information into a cohesive message. Perhaps it was only when children produced gesture that they were able to non-verbally access the encoded gestural content and convert it into speech. While children’s own gesture appears to be the driving force in improving children’s learning and recall, adults must be aware of the way they move their hands during educational lessons, as these gestures likely set the stage for how children themselves will gesture.</p>

Hands-on learning: The influence of hand gestures on children's recall of scientific information

<p>When people speak they typically also gesture. Gesture and speech form an integrated communication system, with speech conveying information in a rule-bound and sequential manner (i.e. one word follows the other in accordance with grammatical rules) while gesture conveys information holistically in a visuospatial representation. These gestural hand movements not only aid the process of speaking, but also convey important information to the listener. While observing gesture during learning can facilitate children’s understanding and remembering of novel and isolated information (e.g.(Cook, Duffy, & Fenn, 2013), observing gesture may also support children in recalling complex, discursive content. This thesis examined the role observing gesture may play in supporting children’s learning and recall of narrative, scientific content. The 7- to 9-year-old children, who participated in this program of research, learnt about the solar system either with or without accompanying gestures. Children’s recall was assessed via interviews, both at short delays (one day) and long delays (two weeks or seven months after learning). It was hypothesised that gesture would improve children’s recall by grounding the abstract scientific ideas in a physical representation, disambiguating novel terms, and providing an additional representation for children to process, store, and retrieve. In Study 1, the influence of observing gesture in supporting children’s learning and recall was examined in combination with adult initiated wh-questions. The study was also conducted in the presence of visual aids. Results indicated that observing gesture only had a limited effect on children’s recall in Study 1 (both independently and in combination with wh-questions), so Study 2 examined the role of observing gesture in the absence of additional visual and verbal supports. Children’s recall was assessed both the next day and seven months later. Study 3 then manipulated both the gesture children observed at learning and the gesture children performed during recall the next day (i.e. instructed, allowed or restricted from gesturing). Finally, Study 4 examined children’s recall of spatial terms across the three studies. The overarching results revealed that children who observed gesture during learning tended to report more spatial terms, but did not show improved recall of the facts and concepts taught. When children observed gesture they did, however, produce a greater rate of representational gestures during recall. In particular, children who observed gesture were more likely to mimic the gestures they had observed, and in doing so improve their verbal recall both within the same interview and across interviews. The instruction to produce gesture did not appear to be effective in augmenting the influence of children’s gesture production, but restricting children from gesturing was found to hinder recall. Observing gesture was only indirectly effective in supporting children’s recall. One possible explanation for this findings may be that children found it difficult to integrate the gestural and verbal information into a cohesive message. Perhaps it was only when children produced gesture that they were able to non-verbally access the encoded gestural content and convert it into speech. While children’s own gesture appears to be the driving force in improving children’s learning and recall, adults must be aware of the way they move their hands during educational lessons, as these gestures likely set the stage for how children themselves will gesture.</p>

The Influence of Embedded Music on the Memorization of Mandarin Chinese

The purpose of this study is to determine how embedded music affects verbal memory in the language of Mandarin Chinese. For this purpose, an experiment was conducted where 40 college students were recruited as the participants. Specifically, they were first randomly allocated into four groups, namely the ‘Reading Group’, the ‘Ambient-music Group’, the ‘Embedded-music Group’, and the ‘Finger-tapping Group’. They were then tested for verbal recall of a lyric in terms of both short-term memory and long-term memory. The results showed that the ‘Ambient-music Group’ scored the highest, followed by the ‘Reading Group’, while the ‘Finger-tapping Group’ ranked the third, and the ‘Embedded-music Group’ was at the bottom. The results that the sung version of a lyric was recalled worse than the spoken version conforms to the recent findings, as compared with traditional notions that music can facilitate the memory of language.

How Does Dementia Begin to Manifest in Bipolar Disorder? A Description of Prodromal Clinical and Cognitive Changes

Background: Older adults with bipolar disorder (BD) have increased dementia risk, but signs of dementia are difficult to detect in the context of pre-existing deficits inherent to BD. Objective: To identify the emergence of indicators of early dementia in BD. Methods: One hundred and fifty-nine non-demented adults with BD from the National Alzheimer Coordinating Center (NACC) data repository underwent annual neuropsychological assessment up to 14 years (54.0 months average follow-up). Cognitive performance was examined longitudinally with linear mixed-effects models, and yearly differences between incident dementia and controls cases were examined in the six years prior to diagnosis. Results: Forty participants (25.2%) developed dementia over the follow-up period (‘incident cases’). Alzheimer’s disease was the most common presumed etiology, though this was likely a result of sampling biases within NACC. Incident cases showed declining trajectories in memory, language, and speeded attention two years prior to dementia onset. Conclusion: In a sample of BD patients enriched for Alzheimer’s type dementia, prodromal dementia in BD can be detected up to two years before onset using the same cognitive tests used in psychiatrically-healthy older adults (i.e., measures of verbal recall and fluency). Cognition in the natural course of BD is generally stable, and impairment or marked decline on measures of verbal episodic memory or semantic retrieval may indicate an early neurodegenerative process.

EXPRESS: Investigating the underlying mechanisms of the Enactment Effect: The role of action-object bindings in aiding immediate memory performance

Previous research has established that enacted action-object phrases lead to superior immediate memory performance compared to purely verbal memory. In the current investigation, Experiment 1 examined how enactment separately affects immediate memory for actions and objects in 24 adults by presenting action-object phrases and asking participants to recall either the actions or the objects presented in correct serial order. The results showed that when employed at presentation, enactment led to superior recall performance compared to verbal repetition, but this effect was significant only for memory for actions and not objects. Enactment during immediate recall did not lead to better memory performance compared to verbal recall for either actions or objects. In order to examine whether the lack of an enactment at recall was due to the splitting of action-object phrases at retrieval, Experiment 2 (n=24) examined memory for whole action-object phrases under enactment at recall. The results showed a typical enactment at recall benefit. Furthermore, a novel binding analysis showed that enactment recall increased the likelihood of action features being remembered in a bound pair rather than alone. Together these findings suggest that action-object bindings play a crucial role in the manifestation of the enactment effect in immediate recall, especially when enactment is employed at the recall phase.

EEG biomarkers of free recall

Brain activity in the moments leading up to successful verbal recall provide a window into the cognitive processes underlying memory retrieval. But these same recordings also subsume neural signals unrelated to mnemonic retrieval, such as response-related motor activity. Here we examined spectral EEG biomarkers of successful recall under an extreme manipulation of mnemonic demands: subjects either recalled items after a few seconds or several days. This manipulation isolated EEG components specifically re- lated to episodic retrieval. Theta and gamma power (4-8 Hz and 40-128 Hz respectively) increased immediately prior to long-delay recall, whereas 8-20 Hz power decreased. A direct comparison of long-delay and immediate recall revealed a nearly identical pattern, indicating that these spectral biomarkers of successful retrieval reflect memory-specific processes. Ruling out a confound of motor related activity, these results identify theta and gamma activity as biomarkers of successful episodic memory retrieval.

Lowered cognitive function and the risk of the first events of cardiovascular diseases: findings from a cohort study in Lithuania

Background The purpose of this prospective cohort study was to examine whether the level of cognitive function at the baseline expressed as a cognitive function composite score and score of specific domains predict the risk of first cardiovascular disease (CVD) events in middle-aged and older populations. Methods Seven thousand eighty-seven participants, men and women aged 45–72 years, were assessed in the baseline survey of the Health Alcohol Psychosocial Factors in Eastern Europe (HAPIEE) study in 2006–2008 in the city of Kaunas, Lithuania. During 10 years of follow-up, the risk of first non-fatal events of CVD and death from CVD (excluding those participants with a documented history of CVD and/or ischemic heart disease (IHD) diagnosed at the baseline survey) was evaluated. Cox proportional hazards regression models were applied to examine how cognitive function predicts the first events of CVD. Results During the follow-up, there were 156 deaths from CVD (49 women and 107 men) and 464 first non-fatal CVD events (195 women and 269 men) registered. The total number of first CVD events was 620 (11.5%). After adjustment for sociodemographic factors, biological and lifestyle risk factors and illnesses, a decrease per 1 standard deviation in different cognitive function scores significantly increased the risk of a first event of CVD (immediate verbal recall score - by 17% in men and 32% in women; delayed verbal recall score – by 17% in men and 24% in women; and a composite score of cognitive function – by 15% in men and 29% in women). Kaplan-Meier survival curves for the probability of a first cardiovascular event according to the categories of a composite score of cognitive function, revealed that a lowered cognitive function predicts a higher probability of the events compared to normal cognitive function (p < 0.05). Conclusions The findings of this follow-up study suggest that men and women with lower cognitive functions have an increased risk for a first event of CVD compared to participants with a higher level of cognitive functions.