Brandy L. Callahan

Smooth pursuit in schizophrenia: A meta-analytic review of research since 1993

Abnormal smooth pursuit eye-tracking is one of the most replicated deficits in the psychophysiological literature in schizophrenia [Levy, D. L., Holzman, P. S., Matthysse, S., & Mendell, N. R. (1993). Eye tracking dysfunction and schizophrenia: A critical perspective. Schizophrenia Bulletin, 19, 461-505]. We used meta-analytic procedures to quantify patient-control differences in eye-tracking and to evaluate potential moderators of effect size including patient and target characteristics and characteristics of the control population (matched or not). The magnitude of patient-control differences in pursuit depended on the measure. Global measures had large effect sizes. Among specific measures, maintenance gain and leading saccades yielded large effect sizes, with gain also yielding the narrowest confidence interval. Effect sizes associated with specific measures of smooth pursuit vs. specific measures of intrusive saccades did not clearly implicate one system over the other. Patient demographics and target characteristics generally had little influence on effect sizes. However, studies that failed to sex-match patients and controls tended to have smaller effect sizes for maintenance gain and catch-up saccade rate. Average effect sizes and confidence limits for global measures of pursuit and for maintenance gain place these measures alongside the very strongest neurocognitive measures in the literature [Heinrichs, R. W. (2004). Meta-analysis, and the science of schizophrenia: Variant evidence or evidence of variants? Neuroscience and Biobehavioral Reviews, 28, 379-394] for distinguishing between patients with schizophrenia and controls.

Liberal bias mediates emotion recognition deficits in frontal traumatic brain injury

It is well-known that patients having sustained frontal-lobe traumatic brain injury (TBI) are severely impaired on tests of emotion recognition. Indeed, these patients have significant difficulty recognizing facial expressions of emotion, and such deficits are often associated with decreased social functioning and poor quality of life. As of yet, no studies have examined the response patterns which underlie facial emotion recognition impairment in TBI and which may lend clarity to the interpretation of deficits. Therefore, the present study aimed to characterize response patterns in facial emotion recognition in 14 patients with frontal TBI compared to 22 matched control subjects, using a task which required participants to rate the intensity of each emotion (happiness, sadness, anger, disgust, surprise and fear) of a series of photographs of emotional and neutral faces. Results first confirmed the presence of facial emotion recognition impairment in TBI, and further revealed that patients displayed a liberal bias when rating facial expressions, leading them to associate intense ratings of incorrect emotional labels to sad, disgusted, surprised and fearful facial expressions. These findings are generally in line with prior studies which also report important facial affect recognition deficits in TBI patients, particularly for negative emotions.

Development of cognitive screening test for the severely hearing impaired: Hearing-impaired MoCA

To develop a version of the Montreal Cognitive Assessment (MoCA) to be administered to the severely hearing impaired (HI‐MoCA), and to assess its performance in two groups of cognitively intact adults over the age of 60.

Normative Data for the Rey–Osterrieth and the Taylor Complex Figure Tests in Quebec-French People

The Rey-Osterrieth (ROCF) and Taylor (TCF) complex figure tests are widely used to assess visuospatial and constructional abilities as well as visual/non-verbal memory. Normative data adjusted to the cultural and linguistic reality of older Quebec-French individuals is still nonexistent for these tests. In this article, we report the results of two studies that aimed to establish normative data for Quebec-French people (aged at least 50 years) for the copy, immediate recall, and delayed recall trials of the ROCF (Study 1) and the TCF (Study 2). For both studies, the impact of age, education, and sex on test performance was examined. Moreover, the impact of copy time on test performance, the impact of copy score on immediate and delayed recall score, and the impact of immediate recall score on delayed recall performance were examined. Based on regression models, equations to calculate Z scores for copy and recall scores are provided for both tests.

Subjective sleep quality in non‐demented older adults with and without cognitive impairment

Sleep problems are prevalent among older adults who are at risk of developing dementia. Until now, there have been relatively few studies investigating subjective sleep quality in these individuals. The first objective of this study was to compare seniors with cognitive impairment no dementia (CIND) and older adults without cognitive impairment (non‐CIND) on several subjective sleep measures. The second objective was to verify whether sleep parameters associated with CIND differ between men and women.

Impact of Depressive Symptoms on Memory for Emotional Words in Mild Cognitive Impairment and Late-Life Depression

BACKGROUND Amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) are associated with increased risk of Alzheimers disease (AD). This is also true for aMCI with concomitant depressive symptoms (aMCI/D+), but few studies have investigated this syndrome. OBJECTIVES We aimed to clarify the association between cognitive and depressive symptoms in individuals at risk for AD by examining episodic memory for emotional stimuli in aMCI, aMCI/D+, and LLD. METHODS Participants were 34 patients with aMCI, 20 patients with aMCI/D+, 19 patients with LLD, and 28 healthy elderly adults. In an implicit encoding task, participants rated the emotional valence of 12 positive, 12 negative, and 12 neutral words. Immediately and 20 minutes later, participants recalled as many words as possible. They were also asked to identify previously presented words during a yes/no recognition trial. RESULTS At immediate recall, aMCI participants displayed better recall of emotional words, particularly positive words. aMCI/D+ and control participants displayed better recall of positive and negative words compared to neutral words. LLD participants recalled more negative than neutral words. At delayed recall, emotional words were generally better-remembered than neutral words by all groups. At recognition, all subjects responded more liberally to emotional than to neutral words. CONCLUSION We find that the type of emotional information remembered by aMCI patients at immediate recall depends on the presence or absence of depressive symptoms. These findings contribute to identifying sources of heterogeneity in individuals at risk for AD, and suggest that the cognitive profile of aMCI/D+ is different from that of aMCI and LLD. Future studies should systematically consider the presence of depressive symptoms in elderly at-risk individuals.

Semantic Memory Impairment for Biological and Man-Made Objects in Individuals With Amnestic Mild Cognitive Impairment or Late-Life Depression

Objective: Amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) both increase the risk of developing Alzheimer disease (AD). Very little is known about the similarities and differences between these syndromes. The present study addresses this issue by examining the nature of semantic memory impairment (more precisely, object-based knowledge) in patients at risk of developing AD. Methods: Participants were 17 elderly patients with aMCI, 18 patients with aMCI plus depressive symptoms (aMCI/D+), 15 patients with LLD, and 29 healthy controls. All participants were aged 55 years or older and were administered a semantic battery designed to assess semantic knowledge for 16 biological and 16 man-made items. Results: Overall performance of aMCI/D+ participants was significantly worse than the 3 other groups, and performance for questions assessing knowledge for biological items was poorer than for questions relating to man-made items. Conclusion: This study is the first to show that aMCI/D+ is associated with object-based semantic memory impairment. These results support the view that semantic deficits in aMCI are associated with concomitant depressive symptoms. However, depressive symptoms alone do not account exclusively for semantic impairment, since patients with LLD showed no semantic memory deficit.

Normative data for the Dementia Rating Scale-2 in the French-Quebec population.

The Dementia Rating Scale-2 is used to measure cognitive status of adults with cognitive impairment, especially of the degenerative type, by assessing five cognitive functions, namely attention, initiation/perseveration, construction, conceptualization, and memory. The present study aimed to establish normative data for this test in the elderly French-Quebec population. A total of 432 French-speaking elders from the province of Quebec (Canada), aged 50 to 85 years, were administered the Dementia Rating Scale-2. Age and education were found to be associated with the total score on the test, while gender was not. Percentile ranks were then calculated for age- and education-stratified groups. Previous studies have shown that cultural background can affect performance on the DRS and the development of culture-specific norms for French-speaking Quebecers could be very useful to clinicians and researchers working with this population.

Antihypertensive Treatment is associated with MRI-Derived Markers of Neurodegeneration and Impaired Cognition: A Propensity-Weighted Cohort Study

BACKGROUND Hypertension is an important risk factor for Alzheimers disease (AD) and cerebral small vessel disease. Angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are common anti-hypertensive treatments, but have differential effects on cortical amyloid. OBJECTIVE The objective of this study was to evaluate associations between anti-hypertensive treatment, brain volume, and cognition, using a propensity-weighted analysis to account for confounding by indication. METHODS We identified a cohort of normal elderly adults and individuals with mild cognitive impairment (MCI) or AD (N = 886; mean age = 75.0) from the Alzheimers Disease Neuroimaging Initiative. Primary outcomes were brain parenchymal fraction, total hippocampal volume, and white matter hyperintensity (WMH) volume. Secondary outcomes were standardized scores on neuropsychological tests. Propensity-weighted adjusted multivariate linear regression was used to estimate associations between anti-hypertensive treatment class and MRI volumes and cognition. RESULTS Individuals treated with ARBs showed larger hippocampal volumes (R2 = 0.83, p = 0.05) and brain parenchymal fraction (R2 = 0.83, p = 0.01) than those treated with ACEIs. When stratified by diagnosis, this effect remained only in normal elderly adults and MCI patients, and a significant association between ARBs and lower WMH volume (R2 = 0.83, p = 0.03) emerged for AD patients only. ARBs were also associated with significantly better performance on tests of episodic and verbal memory, language, and executive function (all p < 0.05). CONCLUSIONS Findings are consistent with evidence for a neuroprotective effect of treatment with ARBs for brain structure and cognition. This study has potential implications for the treatment of hypertension, particularly in elderly adults at risk of cognitive decline and AD.

Functional Reserve: Experience Participating in Instrumental Activities of Daily Living is Associated with Gender and Functional Independence in Mild Cognitive Impairment

BACKGROUND Gender differences in instrumental activities of daily living (IADLs) in mild cognitive impairment (MCI) and Alzheimers disease may be explained by gender differences in IADL involvement. OBJECTIVE We introduce a novel theoretical construct, termed functional reserve, and empirically examine gender differences in IADL experience as a proxy of this reserve. METHODS We cross-sectionally examined men (n = 502) and women (n = 340) with MCI from the Alzheimers Disease Neuroimaging Initiative (ADNI). Demographic factors, depressive symptoms, neuropsychological scores, and IADL experience were included as independent variables and total Functional Activities Questionnaire (FAQ) scores as the dependent variable. Regression analyses were performed on the full cohort and stratified by gender to identify differential predictive relationships for men and women. RESULTS Gender was associated with total FAQ (p < 0.05) until adjusting for IADL experience. Furthermore, the combination of cognitive measures accounted for the most variance in functional dependence (12% explained, p < 0.001), although IADL experience was the most important single variable (4.8% explained, p < 0.001). Stratification by gender revealed that IADL experience accounted for 6.6% of the variance in FAQ score in men (p < 0.001) but only 2.4% in women (p = 0.001); however, the interaction between gender and experience was not statistically significant. DISCUSSION A small effect of men showing greater functional dependence in MCI may be explained by lower IADL experience. Additionally, IADL experience was associated with superior functioning in all analyses, potentially through increased functional reserve. This concept of functional reserve may have implications for identifying individuals at risk for IADL dependence, preventing or delaying decline, and potentially treating functional impairment.