Interhemispheric distribution of Alzheimer disease and vascular pathology in brain aging

BACKGROUND AND PURPOSE: Most of the neuropathological studies in brain aging were based on the assumption of a symmetrical right-left hemisphere distribution of both Alzheimer disease and vascular pathology. To explore the impact of asymmetrical lesion formation on cognition, we performed a clinicopathological analysis of 153 cases with mixed pathology except macroinfarcts. METHODS: Cognitive status was assessed prospectively using the Clinical Dementia Rating scale; neuropathological evaluation included assessment of Braak neurofibrillary tangle and Ass deposition staging, microvascular pathology, and lacunes. The right-left hemisphere differences in neuropathological scores were evaluated using the Wilcoxon signed rank test. The relationship between the interhemispheric distribution of lesions and Clinical Dementia Rating scores was assessed using ordered logistic regression. RESULTS: Unlike Braak neurofibrillary tangle and Ass deposition staging, vascular scores were significantly higher in the left hemisphere for all Clinical Dementia Rating scores. A negative relationship was found between Braak neurofibrillary tangle, but not Ass staging, and vascular scores in cases with moderate to severe dementia. In both hemispheres, Braak neurofibrillary tangle staging was the main determinant of cognitive decline followed by vascular scores and Ass deposition staging. The concomitant predominance of Alzheimer disease and vascular pathology in the right hemisphere was associated with significantly higher Clinical Dementia Rating scores. CONCLUSIONS: Our data show that the cognitive impact of Alzheimer disease and vascular lesions in mixed cases may be assessed unilaterally without major information loss. However, interhemispheric differences and, in particular, increased vascular and Alzheimer disease burden in the right hemisphere may increase the risk for dementia in this group.

Evaluation of self-esteem before and after preceptorship experience for student nurses

seventy-eight diploma nursing students participated (from a class of 112 students) in completing the Coopersmith Self-Esteem Inventory administered by mailed questionnaire before and at the end of the preceptorship. Also a rating form was completed by 70 preceptors to determine how the observed level of self-confidence compared to self-reported self-esteem at the end of the preceptorship program. As well, four preceptors and five preceptees completed weekly diaries and six preceptors and six preceptees participated in weekly phone interviews with the investigator. Overall, self-esteem went up after the preceptorship. A comparison was made between the pretest and posttest using the t-test (dependent paired samples). Significant difference (p=.05) was demonstrated. Self-confidence ratings by preceptors were inaccurate as they had no relation to the self-reported self-esteem level of students. The diaries and interviews of preceptors and preceptees were a rich source of data as well.

Physical activity of children with developmental coordination disorder in the presence of attention deficit hyperactivity disorder : does gender matter?

Baerg, S., Cairney, J., Hay, J., Rempel, L. and Faught, B.E. (2009). Physical Activity of Children with Developmental Coordination Disorder in the Presence of Attention Deficit Hyperactivity Disorder: Does Gender Matter? Brock University, St. Catharines, Ontario, CANADA. Children with Developmental Coordination Disorder (DCD) have difficulties in motor coordination. Attention-deficit hyperactive disorder (ADHD) is considered the condition most co-morbid with DCD at approximately 50%. Children with DCD are generally less physically active (PA) than their peers, while children with ADHD are often considered more physically active. It is not known if the physical activity patterns of children with DCD-ADHD resemble those of children with primarily DCD or that of their healthy peers. The primary objective of this research was to contrast physical activity patterns between children with DCD, DCD-ADHD, and healthy controls. Since boys are generally reported as more physically active than girls, a secondary objective was to determine if gender moderated the association between groups and physical activity. A sample of males (n=66) and females (n=44) were recruited from the Physical Health Activity Study Team (PHAST) longitudinal study. The Movement Assessment Battery for Children (2nd Ed.) was used to identify probable cases of DCD, and Connor's Revised Parent Rating Scale- Short Version to identify ADHD. Subjects (mean age=12.8±.4 yrs) were allocated to three groups; DCD (n=32), DCD-ADHD (n=30) and control (n=48). Physical activity was monitored for seven days with the Actical® accelerometer (activity count, step count and energy expenditure). Children completed the Participation Questionnaire (PQ) during the in-school session of data collection for the PHAST study. Height, weight and body mass index (BMI) were also determined. Analysis of variance showed significant group differences for activity count (F(2,56)=5.36, p=.007) and PQ (F(2,44 )=6. 71, p=.003) in males, while a significant group difference for step count (F(2,37)=3.55, p=.04) was found in females. Post hoc comparison tests (Tukey) identified significantly lower PQ and activity count between males with OCD and controls (p=.004) and males with DCD-ADHD and controls (p=.003). Conversely, females with DCD-ADHD had significantly more step counts than their controls (p=.01). Analysis of covariance demonstrated a gender by DCD groups negative interaction for males (activity count) (F(2,92):;:3.11, p=.049) and a positive interaction for females (step count) (F(1,92)=4.92, p=.009). Hyperactivity in females with DCD-ADHD appears to contribute to more physical activity, whereas DCD may contribute to decreased activity in males with DCD and DCDADHD. Further research is needed to examine gender differences in physical activity within the context of DCD and ADHD.

Problem children with and without communication delays : the changes in their parents' report of challenging behaviour, parental hassles and family conflict over a two -year period

The goal of this study was to examine the change, over a two year period, in mothers' reports of children's challenging behaviour and family conflict as they relate to change in parenting hassles (stress) among families who have preschool children with and without communication delays. Forty-four parent-child dyads participated in this Family Resource Project study that was funded by the Canadian Language and Literacy Research Network. Thirty-one ofthese families had preschool children with communication delays and 13 children were identified as not having communication delays. Child behaviour was evaluated using the Oppositional Subscale and ADHD Index of the Conners Parent Rating Scale (CPRS-R:S), the Conflict Subscale ofthe Family Environment Scale was used to examine family conflict, and the Parent Hassles Scale was used to examine parental stress. Results showed that change in mothers' daily hassles was influenced by change in their preschool children's ADHD behaviour and change in family conflict. Change in child oppositional behaviour did not predict change in mothers' hassles scores.

The Informational Value of Corporate Credit Ratings

This thesis examines the quality of credit ratings issued by the three major credit rating agencies - Moody’s, Standard and Poor’s and Fitch. If credit ratings are informative, then prices of underlying credit instruments such as fixed-income securities and credit default insurance should change to reflect the new credit risk information. Using data on 246 different major fixed income securities issuers and spanning January 2000 to December 2011, we find that credit default swaps (CDS) spreads do not react to changes in credit ratings. Hence credit ratings for all three agencies are not price informative. CDS prices are mostly determined by historical CDS prices while ratings are mostly determined by historical ratings. We find that credit ratings are marginally more sensitive to CDS than CDS are sensitive to ratings.

Hot cognition and activation of the medial prefrontal cortex: Self-regulating in contexts involving motivational pressures

The medial prefrontal cortex (mPFC) is involved in performance-monitoring and has been implicated in the generation of several electrocortical responses associated with self-regulation. The error-related negativity (ERN), the inhibitory Nogo N2 (N2), and the feedback-related negativity (FRN) are event-related potential (ERP) components which reflect mPFC activity associated with feedback to behavioural (ERN, N2) and environmental (FRN) consequences. Our main goal was to determine whether or not rnPFC activation varies as a function of motivational context (e.g., those involving performance-related incentives) or the use of internally versus externally generated feedback signals (i.e., errors). Additionally, we assessed medial prefrontal activity in relation to individual differences in personality and temperament. Participants completed a combination of tasks in which performance-related incentives were associated with task performance and feedback generated from internal versus external responses. MPFC activity was indexed using both ERP scalp voltage peaks and intracerebral current source density (CSD) of dorsal and ventral regions. Additionally, participants completed several questionnaires assessing personality and temperament styles. Given previous studies have shown that enhanced mPFC activity to loss (or negative) feedback, we expected that activity in the mPFC would generally be greater during the Loss condition relative to the Win condition for both the ERN and N2. Also, due to the evidence that the (vmPFC) is engaged in arousing contexts, we hypothesized that activity in the ventromedial prefrontal cortex (vmPFC) would be greater than activity in the dorsomedial prefrontal cortex (dmPFC), especially in the Loss condition of the GoNogo task (ERN). Similarly, loss feedback in the BART (FRN) was expected to engage the vmPFC more than the dmPFC. Finally, we predicted that persons rating themselves as more willing to engage in approach-related behaviours or to exhibit rigid cognitive styles would show reduced activity of the mPFC. Overall, our results emphasize the role of affective evaluations of behavioural and environmental consequences when self-regulating. Although there were no effects of context on brain activity, our data indicate that, during the time of the ERN and N2 on the MW Go-Nogo task and the FRN on the BART, the vrnPFC was more active compared to the dmPFC. Moreover, regional recruitment in the mPFC was similar across internally (ERN) and externally (FRN) generated errors signals associated with loss feedback, as reflected by relatively greater activity in the vmPFC than the dmPFC. Our data also suggest that greater activity in the mPFC is associated with better inhibitory control, as reflected by both scalp and CSD measures. Additionally, deactivation of the subgenual anterior cingulate cortex (sgACC) and lower levels of self-reported positive affect were both related to increased voluntary risk-taking on the BART. Finally, persons reporting higher levels of approach-related behaviour or cognitive rigidity showed reduced activity of the mPFC. These results are in line with previous research emphasizing that affect/motivation is central to the processes reflected by mediofrontal negativities (MFNs), that the vmPFC is involved in regulating demands on motivational/affective systems, and that the underlying mechanisms driving these functions vary across both individuals and contexts.

Genetic and Electrophysiological Correlates of Self-Regulation in Adolescence

Self-regulation is considered a powerful predictor of behavioral and mental health outcomes during adolescence and emerging adulthood. In this dissertation I address some electrophysiological and genetic correlates of this important skill set in a series of four studies. Across all studies event-related potentials (ERPs) were recorded as participants responded to tones presented in attended and unattended channels in an auditory selective attention task. In Study 1, examining these ERPs in relation to parental reports on the Behavior Rating Inventory of Executive Function (BRIEF) revealed that an early frontal positivity (EFP) elicited by to-be-ignored/unattended tones was larger in those with poorer self-regulation. As is traditionally found, N1 amplitudes were more negative for the to-be-attended rather than unattended tones. Additionally, N1 latencies to unattended tones correlated with parent-ratings on the BRIEF, where shorter latencies predicted better self-regulation. In Study 2 I tested a model of the associations between selfregulation scores and allelic variations in monoamine neurotransmitter genes, and their concurrent links to ERP markers of attentional control. Allelic variations in dopaminerelated genes predicted both my ERP markers and self-regulatory variables, and played a moderating role in the association between the two. In Study 3 I examined whether training in Integra Mindfulness Martial Arts, an intervention program which trains elements of self-regulation, would lead to improvement in ERP markers of attentional control and parent-report BRIEF scores in a group of adolescents with self-regulatory difficulties. I found that those in the treatment group amplified their processing of attended relative to unattended stimuli over time, and reduced their levels of problematic behaviour whereas those in the waitlist control group showed little to no change on both of these metrics. In Study 4 I examined potential associations between self-regulation and attentional control in a group of emerging adults. Both event-related spectral perturbations (ERSPs) and intertrial coherence (ITC) in the alpha and theta range predicted individual differences in self-regulation. Across the four studies I was able to conclude that real-world self-regulation is indeed associated with the neural markers of attentional control. Targeted interventions focusing on attentional control may improve self-regulation in those experiencing difficulties in this regard.

DONATION DECISIONS: THE ROLES OF FINANCIAL AND EMOTIONAL INFORMATION

This paper investigates the impact of personal affinity toward a charity and information regarding financial management of potential recipient charitable organizations on decisions to donate. Using an experiment, the study examines how personal donation decisions differ from corporate donation decisions made by managers and how the emotional intelligence of donors affects donation decisions. The results indicate that threshold and financial information on charities assembled by the Better Business Bureau, a charity rating agency, made a significant impact on corporate donation decisions. The study also shows that emotional intelligence plays an important role that aids both individual donors and managers to regulate their donation decisions.

Moderators of the Relationship between Family Caregiver Proxy-Ratings and Person with Dementia Self-Ratings of Quality of Life

As the dementia spectrum lacks any viable cure, quality of life is typically regarded as an essential measure of assessing the clinical course and evaluating interventions. With caregivers typically providing this rating to health professionals, the literature has noted inconsistencies between caregiver and person with dementia (PwD) ratings of quality of life and suggested several factors may moderate the rating relationship. To investigate this, an intraclass correlation coefficient was calculated to observe rating agreement and moderator regression analysis was conducted to explore potential moderators. Potential moderators of caregiver burden, caregiver age, caregiver income, PwD IADLs/ADLs, PwD education, PwD cognitive impairment, PwD depressive symptom severity, PwD behavioural symptom severity, as well as relationship between caregiver and PwD. Utilizing secondary data from 107 recruited dyads, analyses conducted found fair agreement between caregivers and those with dementia while none of the hypothesized factors were found to moderate the rating relationship.

Estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell

Estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell, contractors, on sections 1, 2, and 3 ending at St. Catharines during the month ending Aug. 31, 1854.

Estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell

Estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell, contractors, on sections 1, 2, and 3 ending at St. Catharines during the month of August, 1854, signed by S.D. Woodruff, Sept. 1854.

Memorandum of expenses for work done and materials provided by Messrs. Brown and McDonell

Memorandum of expenses for work done and materials provided by Messrs. Brown and McDonell, contractors for the Port Dalhousie and Thorold Railway to Sept. 1, 1854, signed by S.D. Woodruff, Sept. 2, 1854.

Estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell

Estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell, contractors, on sections 1, 2, and 3 ending at St. Catharines during the month ending Sept. 30, 1854.

Chart of estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell

Chart of estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell, contractors, on sections 1, 2, and 3 ending at St. Catharines for the month of Jan. 1855, signed by S.D. Woodruff, Feb. 1855.

Chart of estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell

Chart of estimate of work done on the Port Dalhousie and Thorold Railway by Messrs. Brown and McDonell, contractors, on sections 1, 2, and 3 ending at St. Catharines for the months of Feb. and March, 1855, signed by S.D. Woodruff, Apr. 1855.