Correlation between disease severity and brain electric LORETA tomography in Alzheimer's disease

OBJECTIVE To compare EEG power spectra and LORETA-computed intracortical activity between Alzheimer's disease (AD) patients and healthy controls, and to correlate the results with cognitive performance in the AD group. METHODS Nineteen channel resting EEG was recorded in 21 mild to moderate AD patients and in 23 controls. Power spectra and intracortical LORETA tomography were computed in seven frequency bands and compared between groups. In the AD patients, the EEG results were correlated with cognitive performance (Mini Mental State Examination, MMSE). RESULTS AD patients showed increased power in EEG delta and theta frequency bands, and decreased power in alpha2, beta1, beta2 and beta3. LORETA specified that increases and decreases of power affected different cortical areas while largely sparing prefrontal cortex. Delta power correlated negatively and alpha1 power positively with the AD patients' MMSE scores; LORETA tomography localized these correlations in left temporo-parietal cortex. CONCLUSIONS The non-invasive EEG method of LORETA localized pathological cortical activity in our mild to moderate AD patients in agreement with the literature, and yielded striking correlations between EEG delta and alpha1 activity and MMSE scores in left temporo-parietal cortex. SIGNIFICANCE The present data support the hypothesis of an asymmetrical progression of the Alzheimer's disease.

Dyadic action control in overweight and obese couples: Effectiveness of a randomized controlled trial to promote physical activity.

BACKGROUND: Enhancing physical activity in overweight and obese individuals is an important means to promote health in this target population. The Health Action Process Approach (HAPA), which was the theoretical framework of this study, focuses on individual self-regulation variables for successful health behavior change. One key self-regulation variable of this model is action control with its three subfacets awareness of intentions, self-monitoring and regulatory effort. The social context of individuals, however, is usually neglected in common health behavior change theories. In order to integrate social influences into the HAPA, this randomized controlled trial investigated the effectiveness of a dyadic conceptualization of action control for promoting physical activity. METHODS/DESIGN: This protocol describes the design of a single-blind randomized controlled trial, which comprises four experimental groups: a dyadic action control group, an individual action control group and two control groups. Participants of this study are overweight or obese, heterosexual adult couples who intend to increase their physical activity. Blocking as means of a gender-balanced randomization is used to allocate couples to conditions and partners to either being the target person of the intervention or to the partner condition. The ecological momentary intervention takes place in the first 14 days after baseline assessment and is followed by another 14 days diary phase without intervention. Follow-ups are one month and six months later. Subsequent to the six-months follow-up another 14 days diary phase takes place.The main outcome measures are self-reported and accelerometer-assessed physical activity. Secondary outcome measures are Body Mass Index (BMI), aerobic fitness and habitual physical activity. DISCUSSION: This is the first study examining a dyadic action control intervention in comparison to an individual action control condition and two control groups applying a single-blind randomized control trial. Challenges with running couples studies as well as advantages and disadvantages of certain design-related decisions are discussed. This RCT was funded by the Swiss National Science Foundation (PP00P1_133632/1) and was registered on 27/04/2012 at http://www.isrctn.com/ISRCTN15705531.

Sports after Busy Work: Work-Related Cognitive Failure Corresponds to Risk Bearing Behaviors and Athletic Injury

Although employees are encouraged to take exercise after work to keep physically fit, they should not suffer injury. Some sports injuries that occur after work appear to be work-related and preventable. This study investigated whether cognitive failure mediates the influence of mental work demands and conscientiousness on risk-taking and risky and unaware behaviour during after-work sports activities. Participants were 129 employees (36% female) who regularly took part in team sports after work. A structural equation model showed that work-related cognitive failure significantly mediated the influence of mental work demands on risky behaviour during sports (p < .05) and also mediated the directional link between conscientiousness and risky behaviour during sports (p < .05). A path from risky behaviour during sports to sports injuries in the last four weeks was also significant (p < .05). Performance constraints, time pressure, and task uncertainty are likely to increase cognitive load and thereby boost cognitive failures both during work and sports activities after work. Some sports injuries after work could be prevented by addressing the issue of work redesign.

Autocatalytic activity and substrate specificity of the pestivirus N-terminal protease Npro.

Pestivirus N(pro) is the first protein translated in the viral polypeptide, and cleaves itself off co-translationally generating the N-terminus of the core protein. Once released, N(pro) blocks the host׳s interferon response by inducing degradation of interferon regulatory factor-3. N(pro׳)s intracellular autocatalytic activity and lack of trans-activity have hampered in vitro cleavage studies to establish its substrate specificity and the roles of individual residues. We constructed N(pro)-GFP fusion proteins that carry the authentic cleavage site and determined the autoproteolytic activities of N(pro) proteins containing substitutions at the predicted catalytic sites Glu22 and Cys69, at Arg100 that forms a salt bridge with Glu22, and at the cleavage site Cys168. Contrary to previous reports, we show that N(pro׳)s catalytic activity does not involve Glu22, which may instead be involved in protein stability. Furthermore, N(pro) does not have specificity for Cys168 at the cleavage site even though this residue is conserved throughout the pestivirus genus.

Digital Personal Assistant for Cognitive Cities: A Paper Prototype

This chapter presents an evaluation and initial testing of a meta-application (meta-app) for enhanced communication and improved interaction (e.g., appointment scheduling) between stakeholders (e.g., citizens) in cognitive cities. The underlying theoretical models as well as the paper prototype are presented to ensure the comprehensibility of the user interface. This paper prototype of the meta-app was evaluated through interviews with various experts in different fields (e.g., a strategic consultant, a small and medium-sized enterprises cofounder in the field of online marketing, an IT project leader, and an innovation manager). The results and implications of the evaluation show that the idea behind this meta-app has the potential to improve the living standards of citizens and to lead to a next step in the realization and maturity of the meta-app. The meta-app helps citizens more effectively manage their time and organize their personal schedules and thus allows them to have more leisure time and take full advantage of it to ensure a good work-life balance to enable them to be the most efficient and productive during their working time.

Acute S100B in serum is associated with cognitive symptoms and memory performance 4 months after paediatric mild traumatic brain injury

OBJECTIVE This study explored whether acute serum marker S100B is related with post-concussive symptoms (PCS) and neuropsychological performance 4 months after paediatric mild traumatic brain injury (mTBI). RESEARCH DESIGN AND METHODS This prospective short-term longitudinal study investigated children (aged 6-16 years) with mTBI (n = 36, 16 males) and children with orthopaedic injuries (OI, n = 27, 18 males) as a control group. S100B in serum was measured during the acute phase and was correlated with parent-rated PCS and neuropsychological performance 4 months after the injury. MAIN OUTCOMES AND RESULTS The results revealed no between-group difference regarding acute S100B serum concentration. In children after mTBI, group-specific significant Spearman correlations were found between S100B and post-acute cognitive PCS (r = 0.54, p = 0.001) as well as S100B and verbal memory performance (r = -0.47, p = 0.006). In children after OI, there were insignificant positive relations between S100B and post-acute somatic PCS. In addition, insignificant positive correlations were found between neuropsychological outcome and S100B in children after OI. CONCLUSIONS S100B was not specific for mild brain injuries and may also be elevated after OI. The group-specific association between S100B and ongoing cognitive PCS in children after mTBI should motivate to examine further the role of S100B as a diagnostic biomarker in paediatric mTBI.

Combining qualitative and quantitative methods to analyze serious games outcomes: A pilot study for a new cognitive screening tool

Computer games for a serious purpose - so called serious games can provide additional information for the screening and diagnosis of cognitive impairment. Moreover, they have the advantage of being an ecological tool by involving daily living tasks. However, there is a need for better comprehensive designs regarding the acceptance of this technology, as the target population is older adults that are not used to interact with novel technologies. Moreover given the complexity of the diagnosis and the need for precise assessment, an evaluation of the best approach to analyze the performance data is required. The present study examines the usability of a new screening tool and proposes several new outlines for data analysis.

Effects of stereotypic behaviour and chronic mild stress on judgement bias in laboratory mice

Cognitive processes are influenced by underlying affective states, and tests of cognitive bias have recently been developed to assess the valence of affective states in animals. These tests are based on the fact that individuals in a negative affective state interpret ambiguous stimuli more pessimistically than individuals in a more positive state. Using two strains of mice we explored whether unpredictable chronic mild stress (UCMS) can induce a negative judgement bias and whether variation in the expression of stereotypic behaviour is associated with variation in judgement bias. Sixteen female CD-1 and 16 female C57BL/6 mice were trained on a tactile conditional discrimination test with grade of sandpaper as a cue for differential food rewards. Once they had learned the discrimination, half of the mice were subjected to UCMS for three weeks to induce a negative affective state. Although UCMS induced a reduced preference for the higher value reward in the judgement bias test, it did not affect saccharine preference or hypothalamic–pituitary–adrenal (HPA) activity. However, UCMS affected responses to ambiguous (intermediate) cues in the judgement bias test. While control mice showed a graded response to ambiguous cues, UCMS mice of both strains did not discriminate between ambiguous cues and tended to show shorter latencies to the ambiguous cues and the negative reference cue. UCMS also increased bar-mouthing in CD-1, but not in C57BL/6 mice. Furthermore, mice with higher levels of stereotypic behaviour made more optimistic choices in the judgement bias test. However, no such relationship was found for stereotypic bar-mouthing, highlighting the importance of investigating different types of stereotypic behaviour separately.

An Exploration Based Cognitive Bias Test for Mice: Effects of Handling Method and Stereotypic Behaviour

Behavioural tests to assess affective states are widely used in human research and have recently been extended to animals. These tests assume that affective state influences cognitive processing, and that animals in a negative affective state interpret ambiguous information as expecting a negative outcome (displaying a negative cognitive bias). Most of these tests however, require long discrimination training. The aim of the study was to validate an exploration based cognitive bias test, using two different handling methods, as previous studies have shown that standard tail handling of mice increases physiological and behavioural measures of anxiety compared to cupped handling. Therefore, we hypothesised that tail handled mice would display a negative cognitive bias. We handled 28 female CD-1 mice for 16 weeks using either tail handling or cupped handling. The mice were then trained in an eight arm radial maze, where two adjacent arms predicted a positive outcome (darkness and food), while the two opposite arms predicted a negative outcome (no food, white noise and light). After six days of training, the mice were also given access to the four previously unavailable intermediate ambiguous arms of the radial maze and tested for cognitive bias. We were unable to validate this test, as mice from both handling groups displayed a similar pattern of exploration. Furthermore, we examined whether maze exploration is affected by the expression of stereotypic behaviour in the home cage. Mice with higher levels of stereotypic behaviour spent more time in positive arms and avoided ambiguous arms, displaying a negative cognitive bias. While this test needs further validation, our results indicate that it may allow the assessment of affective state in mice with minimal training— a major confound in current cognitive bias paradigms.