B vitamins and cognitive performance in older adults: Review

A copious amount of scientific scrutiny has been dedicated to documenting typical and atypical human ageing, with a substantial body of work focusing upon the impact of lifestyle choices. One such lifestyle choice is that of diet and, in particular, micronutrient ingestion. Epidemiological studies have reported positive associations between B vitamin status and cognitive function, including negative associations between biological markers (i.e., homocysteine) of dysregulated one-carbon metabolism and cognitive function. This has led to a surge of randomised control trials (RCTs) investigations into B vitamin therapy. However, results have continuingly failed to show beneficial behavioural effects. Despite this, results reliably show treatment-related increases in B vitamin level and decreases in homocysteine level—both of which have been identified as risk factors for atypical ageing. In this paper we argue that it would be premature to conclude that B vitamin therapy has no potential and that more research is needed to systematically investigate the optimal dose, the therapeutic “window,” and individual differences in therapy responders and nonresponders. We start with a brief look at one-carbon metabolism and then consider the evidence from epidemiological studies and RCTs in relation to three specific B vitamins: folic acid (B9), pyridoxine (B6), and cobamides (B12)

Stranger Danger Awareness in Williams Syndrome

Background: The developmental disorder Williams syndrome (WS) is characterised by a distinctive cognitive profile and an intriguing social phenotype. Individuals with the disorder are often highly social engaging with familiar and unfamiliar people and once in an interaction they often show subtle abnormalities of social behaviour. Atypically increased approach to unfamiliar people is widely reported in the existing literature for both children and adults. Parents frequently report interactions with unfamiliar people as a major concern. Methods: In this study we aimed to evaluate ‘stranger danger’ awareness using a video vignette task with individuals who had WS. When linked to other components of the WS phenotype (e.g. reduced intellectual ability, increased social approach) an awareness of stranger danger is particularly important. Results: Qualitative and quantitative data showed that young people with WS have difficulties making judgements about whether or not to trust and engage in conversation with unfamiliar people. Qualitative data showed that individuals with WS often suggested that they would engage in an interaction with an unfamiliar person. Conclusions: The findings have substantial implications for the safety of young people with the disorder and emphasise the need for intervention regarding this behaviour

Social approach in preschool children with Williams syndrome: The role of the face.

Background Indiscriminate social approach behaviour is a salient aspect of the Williams syndrome (WS) behavioural phenotype. The present study examines approach behaviour in preschoolers with WS and evaluates the role of the face in WS social approach behaviour. Method Ten preschoolers with WS (aged 3-6 years) and two groups of typically developing children, matched to the WS group on chronological or mental age, participated in an observed play session. The play session incorporated social and non-social components including two components that assessed approach behaviour towards strangers, one in which the stranger’s face could be seen and one in which the stranger’s face was covered. Results In response to the non-social aspects of the play session, the WS group behaved similarly to both control groups. In contrast, the preschoolers with WS were significantly more willing than either control group to engage with a stranger, even when the stranger’s face could not be seen. Conclusion The findings challenge the hypothesis that an unusual attraction to the face directly motivates social approach behaviour in individuals with WS

Attentional Lapse and Inhibition Control in Adults with Williams Syndrome

Research exploring cognitive processing associated with Williams Syndrome (WS) has suggested that executive functioning deficits exist across the developmental spectrum. Such executive functions include problem solving, planning, dividing attention and inhibiting responses. Within a framework of executive functions, the aim of the current study was to explore attentional lapse and inhibition skills in older adults with WS (n = 20; aged 36–61 yr) and consider the implications of deficits within this group. Participants with WS were compared to typical adults of the same chronological age and typical older adults (aged 65+ yr) to consider attentional changes seen in the ageing process. The study employed a sustained attention to response task known to assess inhibition and attentional lapse but which had not previously been used with this population. Compared to both groups of typical matches, the results indicated atypicalities of attention and inhibition in adults with WS. Specifically, compared to the typical matches, adults with WS failed to withhold a response (showing inhibition deficits), had problems re-engaging attentional control processes after making an error and showed a generalised deficit of concentration and task engagement. We conclude that further attention should be paid to the cognitive capacity of older individuals with WS in order to consider the everyday challenges faced by this group and to provide adequate intervention and support for daily living

Face processing in Williams Syndrome and autism

Individuals with Williams syndrome (WS) have been characterised as hyper-sociable, showing an extreme compulsion to engage in communication with other people, whilst the opposite has been cited regarding autism. The most important social cue in our environment is the human face, which must be successfully recognised and interpreted for communicative signals. Although clear differences are apparent in social skills, individuals with WS and autism have been described as showing similarly atypical face processing styles. The present research addressed issues of face perception in Williams syndrome and autism to gain further insights into social abilities of individuals with these developmental disorders. Importantly, the research was grounded in typical face perception methods. The investigation began with a large-scale exploration of face skills, probing identity, eye gaze, expressions of emotion and lip reading to ask how these two disorders uniquely impact upon performance. Participants with WS and autism could be dissociated from those with general developmental delay and from each other primarily on the basis of eye gaze ability. Participants with WS showed strong eye gaze abilities whilst participants with autism had extreme difficulties. Although interpretation of expressions of emotion also showed a difference between groups, autism and WS did not uniquely impact upon the processing of identity or lip reading. The exploration also allowed the consideration of models of face perception; characterised by a typical modular structure in WS but a lack of modularity in autism. The second line of inquiry considered identity processing and firstly asked whether participants were more accurate at matching faces from internal or external features. Participants with WS showed an atypical use of internal features for matching unfamiliar faces, which may be linked to an atypical interaction style and exaggerated interest in unfamiliar people. Participants with autism used the same strategy to match faces of familiar and unfamiliar people and hence familiarity did not impact upon processing style. Subsequent chapters probed feature salience (eyes .v. mouth) and structural encoding. Across paradigms typically developing participants and those with WS showed greater accuracy using the eye than mouth region, a pattern not evident in autism. Regarding structural encoding, individuals with WS showed use of configural cues under the task demands implemented in this thesis, where individuals with autism were only able to interpret featural cues. Previous evidence of similar face processing styles in WS and autism were not supported. Taken together the findings provide further insights into face perception and social functioning in WS and autism. The research used the same participants across paradigms, considered level of functioning on the autistic spectrum and included investigations of WS and autism in the same research programme. Additional to the main experimental studies, pilot data is provided to open a new line of investigation into physiological arousal associated with holding eye contact in WS. Therefore, on the basis of the experiments conducted here, a number of suggestions are made to carry the research forward in future investigations. Throughout the thesis as a whole, comparisons are made between individuals with WS and autism that further our understanding of the links between face processing and social expertise.ESRC funde

Retrieval and monitoring processes during visual working memory: An ERP study of the benefit of visual semantics

In this study we examined electrophysiological indices of episodic remembering whilst participants recalled novel shapes, with and without semantic content, within a visual working memory paradigm. The components of interest were the parietal episodic (PE; 400-800ms) and late posterior negativity (LPN; 500-900ms), as these have previously been identified as reliable markers of recollection and post retrieval monitoring, respectively. Fifteen young adults completed a visual matrix patterns task, assessing memory for low and high semantic visual representations. Matrices with either low semantic or high semantic content (containing familiar visual forms) were briefly presented to participants for study (1500ms), followed by a retention interval (6000ms) and finally a same/different recognition phase. The event-related potentials of interest were tracked from the onset of the recognition test stimuli. Analyses revealed equivalent amplitude for the earlier PE effect for the processing of both low and high semantic stimulus types. However, the LPN was more negative-going for the processing of the low semantic stimuli. These data are discussed in terms of relatively ‘pure’ retrieval of high semantic items, where support can readily be recruited from semantic memory. However, for the low semantic items additional executive resources, as indexed by the LPN, are recruited when memory monitoring and uncertainty exist in order to recall previously studied items more effectively

Glucose enhancement of human memory: A comprehensive research review of the glucose memory facilitation effect

The brain relies upon glucose as its primary fuel. In recent years, a rich literature has developed from both human and animal studies indicating that increases in circulating blood glucose can facilitate cognitive functioning. This phenomenon has been termed the ‘glucose memory facilitation effect’. The purpose of this review is to discuss a number of salient studies which have investigated the influence of glucose ingestion on neurocognitive performance in individuals with (a) compromised neurocognitive capacity, as well as (b) normally functioning individuals (with a focus on research conducted with human participants). The proposed neurocognitive mechanisms purported to underlie the modulatory effect of glucose on neurocognitive performance will also be considered. Many theories have focussed upon the hippocampus, given that this brain region is heavily implicated in learning and memory. Further, it will be suggested that glucose is a possible mechanism underlying the phenomenon that enhanced memory performance is typically observed for emotionally laden stimuli

Perfectionism and PERMA: The Benefits of Other-Oriented Perfectionism

The two-factor theory of perfectionism differentiates between positive and negative forms, yet some researchers still argue that perfectionism, as a whole, is detrimental to wellbeing. To this end, the present study investigated the relationship between the tripartite model of perfectionism and the PERMA model of wellbeing, with specific attention given to the relationship each form of perfectionism had with each element of wellbeing. Ninety-two participants (M age= 24.99) completed online self-report measures of perfectionism (self-oriented, other-oriented, and socially prescribed) and PERMA (positive emotion, engagement, relationships, meaning and accomplishment). Results showed that perfectionism accounted for a substantial amount of variance in all elements of wellbeing. A series of multiple regressions showed that socially prescribed perfectionism negatively predicted all PERMA elements. Self-oriented perfectionism positively predicted positive emotion, engagement, meaning and accomplishment. Other-oriented perfectionism positively predicted meaning and accomplishment. As for overall wellbeing, socially prescribed perfectionism was a negative predictor whereas self-oriented and other-oriented perfectionism were positive predictors. The findings indicate that self-oriented perfectionism is an adaptive form of perfectionism conducive to flourishing whereas socially prescribed perfectionism is a maladaptive form which undermines it. As for other-oriented perfectionism, the findings indicate it is an adaptive form and challenge the view that this “dark” form of perfectionism cannot enhance wellbeing

The development of analytical procedures using ICP-OES and ICP-MS for the analysis of trace metals in pharmaceutical formulations

New regulations regarding elemental impurities in pharmaceuticals will be implemented in January 2018 and the guidelines include the use of inductively coupled plasma optical emission spectroscopy (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). In this work, a method using each instrument was developed for the analysis of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), cobalt (Co), nickel (Ni) and vanadium (V) and validated to meet the international conference of harmonisation (ICH Q3D) guidelines. Liquid and solid samples were prepared using microwave assisted acid digestion method that was developed using reverse aqua regia. The results obtained from the validation showed good linearity (R2>0.995) with low limits of detections (LODs) and limits of quantifications (LOQs). The percentage recoveries for both the standard reference material (SRM) and the spiked samples were between 95-105% with relative standard deviation (RSD) of less than 5. Cold symptoms relief products were purchased and analysed. Levels of Pb and Cd in certain products were found to exceed the permitted daily exposure limit (PDE) when the maximum dose was taken

Effects of three different biochars on aggregate stability, organic carbon mobility and micronutrient bioavailability

Previous studies have demonstrated both beneficial and detrimental effects on soil properties from biochar incorporation. Several biochars, with different feedstock origins, were evaluated for their effectiveness at improving soil quality of a sandy agricultural soil. A pot trial was used to investigate aggregate stability and microbial activity, pore water trace element mobility and micronutrient concentrations in grain of spring wheat after incorporation of three biochars. The feedstocks for biochar production were selected because they were established UK waste products, namely oversize woody material from green waste composting facilities, and rhododendron and soft wood material from forest clearance operations. Biochars were incorporated into the soil at a rate of 5% v/v. Aggregate stability was improved following addition of oversize biochar whilst microbial activity increased in all treatments. Dissolved organic carbon (DOC) concentrations in soil pore water from biochar-treated soils were raised, whilst micronutrient concentrations in wheat grain grown in the treated soils were significantly reduced. It was concluded that incorporation of biochar to temperate agricultural soils requires caution as it may result in reductions of essential grain micronutrients required for human health, whilst the effect on aggregate stability may be linked to organic carbon functional groups on biochar surfaces and labile carbon released from the char into the soil system