Clarifying Observed Relationships Between Protective Behavioral Strategies and Alcohol Outcomes: The Importance of Response Options

Protective behavioral strategies (PBS), or harm-reduction behaviors that can potentially reduce alcohol consumption or associated problems, have been assessed in varied ways throughout the literature. Existing scales vary in focus (i.e., broad vs. narrow), and importantly, in response options (i.e., absolute frequency vs. contingent frequency). Absolute frequency conflates PBS use with number of drinking occasions, resulting in inconsistencies in the relationship between PBS use and alcohol outcomes, whereas contingent frequency is less precise, which could reduce power. The current study proposes the use of absolute frequencies to maximize precision, with an adjustment for number of drinking days to extricate PBS use from drinking occasions, resulting in a contingent score. Study 1 examined the associations between PBS subscales using the Strategy Questionnaire (Sugarman & Carey, 2007) and alcohol outcomes, finding that in raw score form the association between PBS and typical alcohol outcomes varied greatly from significantly positive to significantly negative, but adjusted score relationships were all consistent with harm reduction perspectives. In addition, curvilinear relationships with typical alcohol use were eliminated using the score adjustment, resulting in linear associations. Study 2 confirmed the findings from Study 1 with a more precise timeframe, additional alcohol assessments, and heavier college drinkers. The relationships between alcohol outcomes and PBS in raw score form were again varied, but became consistently negative using the score adjustment. Researchers examining PBS and related constructs should consider modifying current scales to include a precise frequency response scale that is adjusted to account for number of drinking occasions

Defining and Characterizing Differences in College Alcohol Intervention Efficacy: A Growth Mixture Modeling Application

Objective: While college alcohol misuse remains a pervasive issue, individual-level interventions are among the most efficacious methodologies to reduce alcohol-related harms. Growth mixture modeling (GMM) was used as an exploratory moderation analysis to determine how many types of college drinkers exist with regard to intervention efficacy over a 12-month period. Method: Data from 3 randomized controlled trials were combined to yield a sample of 1,040 volunteer and mandated college students who were given 1 of 3 interventions: a brief motivational intervention, Alcohol Edu for Sanctions, or Alcohol 101 Plus. Participants were assessed at baseline, and 1, 6, and 12 months post intervention. Results: Through the examination of heavy drinking behaviors, piecewise GMM identified 6 subpopulations of drinkers. Most of the sample (76%) was lighter drinkers who demonstrated a strong intervention response, but returned to baseline behaviors over the subsequent 12 months. In contrast, 11% of the sample reported no significant change over the 12-month period. Four minority subpopulations were also identified. In sum, 82% of the sample responded to intervention, but 84% of the sample reported intervention decay over the subsequent 12 months. Female gender, being an, upperclassmen, beginning drinking later in life, not engaging in drinking games, and lower norms predicted a greater likelihood of responding to intervention. Conclusion: Individual-level interventions are successful at effecting change in most college students, but these effects tend to decay to baseline behaviors by 12 months. These results suggest intervention efforts need to find ways to engage freshmen men and those who play drinking games. Public Health Significance: This study suggests that there are distinct subgroups of college students defined by how they respond to alcohol intervention, and that interventions need to target freshmen men and those who play drinking games. Although most students initially response to intervention effects, most also show intervention decay over the next 12 months, which suggests that we need to determine ways of improving the long-term effects of alcohol interventions

Concordance Among Extension Workers, Researchers, and Professional Arborists in Rating Landscape Trees

Formulas developed to determine the monetary value of landscape trees require a species rating value. Polling Extension professionals, researchers, and arborists is a common procedure to derive species rating value. Due to differences in professional training and background, and the variability of landscapes in any given area, professional agreement on the rating of a species is difficult to reach but is necessary to be useful. The Delphi method and W criterion were used to determine the strength of concordance among extension professionals. We hope that other Extension professionals can use this method in developing species rating in their respective areas

Separating vascular and neuronal effects of age on fMRI BOLD signals.

Accurate identification of brain function is necessary to understand the neurobiology of cognitive ageing, and thereby promote well-being across the lifespan. A common tool used to investigate neurocognitive ageing is functional magnetic resonance imaging (fMRI). However, although fMRI data are often interpreted in terms of neuronal activity, the blood oxygenation level-dependent (BOLD) signal measured by fMRI includes contributions of both vascular and neuronal factors, which change differentially with age. While some studies investigate vascular ageing factors, the results of these studies are not well known within the field of neurocognitive ageing and therefore vascular confounds in neurocognitive fMRI studies are common. Despite over 10 000 BOLD-fMRI papers on ageing, fewer than 20 have applied techniques to correct for vascular effects. However, neurovascular ageing is not only a confound in fMRI, but an important feature in its own right, to be assessed alongside measures of neuronal ageing. We review current approaches to dissociate neuronal and vascular components of BOLD-fMRI of regional activity and functional connectivity. We highlight emerging evidence that vascular mechanisms in the brain do not simply control blood flow to support the metabolic needs of neurons, but form complex neurovascular interactions that influence neuronal function in health and disease. This article is part of the theme issue 'Key relationships between non-invasive functional neuroimaging and the underlying neuronal activity'.This work is supported by the British Academy (PF160048), the Guarantors of Brain (G101149), the Wellcome Trust (103838), the Medical Research Council (SUAG/051 G101400; and SUAG/046 G101400), European Union’s Horizon 2020 (732592) and the Cambridge NIHR Biomedical Research Centre

Neurophysiological and brain structural markers of cognitive frailty differs from Alzheimer’s disease

AbstractWith increasing life span, there is growing importance of understanding the mechanisms of successful cognitive ageing. In contrast, cognitive frailty has been proposed to be a precursor to Alzheimer’s disease. Here we test the hypothesis that cognitively frail adults represent a branch of healthy ageing, distinct from latent dementia. We used electro-magnetoencephalography and magnetic resonance imaging to investigate the structural and neurophysiological features of cognitive frailty in relation to healthy aging, and clinical presentations of mild cognitive impairment and Alzheimer’s disease. Cognitive performance of the cognitively frail group was similar to those with mild cognitive impairment. We used a novel cross-modal oddball task to induce mismatch responses to unexpected stimuli. Both controls and cognitively frail showed stronger mismatch responses and larger temporal grey matter volume, compared to people with mild cognitive impairment and Alzheimer’s disease. Our results suggest that cognitively frail represents a spectrum of normal ageing rather than incipient or undiagnosed Alzheimer’s disease. Lower cognitive reserve, hearing impairment and medical comorbidity might contribute to the aetiology of cognitive impairment.The study was supported by the Medical Research Council [SUAG/004 RG91365, SUAG/046 RG101400; SUAG/051 RG101400], the Wellcome Trust [103838], the Dementias Platform UK [MR/L023784/1 & MR/L023784/2], Alzheimer’s Research UK [ARUK-PG2017B-19], a Holt Fellowship, and NIHR Cambridge Biomedical Research Centre (BRC-1215-20014). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. For the purpose of open access, the author has applied a CC BY public copyright license to any Author Accepted Manuscript version arising from this submission

Effect of apolipoprotein E polymorphism on cognition and brain in the Cambridge Centre for Ageing and Neuroscience cohort.

Polymorphisms in the apolipoprotein E (APOE) gene have been associated with individual differences in cognition, brain structure and brain function. For example, the ε4 allele has been associated with cognitive and brain impairment in old age and increased risk of dementia, while the ε2 allele has been claimed to be neuroprotective. According to the 'antagonistic pleiotropy' hypothesis, these polymorphisms have different effects across the lifespan, with ε4, for example, postulated to confer benefits on cognitive and brain functions earlier in life. In this stage 2 of the Registered Report - https://osf.io/bufc4, we report the results from the cognitive and brain measures in the Cambridge Centre for Ageing and Neuroscience cohort (www.cam-can.org). We investigated the antagonistic pleiotropy hypothesis by testing for allele-by-age interactions in approximately 600 people across the adult lifespan (18-88 years), on six outcome variables related to cognition, brain structure and brain function (namely, fluid intelligence, verbal memory, hippocampal grey-matter volume, mean diffusion within white matter and resting-state connectivity measured by both functional magnetic resonance imaging and magnetoencephalography). We found no evidence to support the antagonistic pleiotropy hypothesis. Indeed, Bayes factors supported the null hypothesis in all cases, except for the (linear) interaction between age and possession of the ε4 allele on fluid intelligence, for which the evidence for faster decline in older ages was ambiguous. Overall, these pre-registered analyses question the antagonistic pleiotropy of APOE polymorphisms, at least in healthy adults

Neurophysiological signatures of Alzheimer's disease and frontotemporal lobar degeneration : pathology versus phenotype

The disruption of brain networks is characteristic of neurodegenerative dementias. However, it is controversial whether changes in connectivity reflect only the functional anatomy of disease, with selective vulnerability of brain networks, or the specific neurophysiological consequences of different neuropathologies within brain networks. We proposed that the oscillatory dynamics of cortical circuits reflect the tuning of local neural interactions, such that different pathologies are selective in their impact on the frequency spectrum of oscillations, whereas clinical syndromes reflect the anatomical distribution of pathology and physiological change. To test this hypothesis, we used magnetoencephalography from five patient groups, representing dissociated pathological subtypes and distributions across frontal, parietal and temporal lobes: amnestic Alzheimer's disease, posterior cortical atrophy, and three syndromes associated with frontotemporal lobar degeneration. We measured effective connectivity with graph theory-based measures of local efficiency, using partial directed coherence between sensors. As expected, each disease caused large-scale changes of neurophysiological brain networks, with reductions in local efficiency compared to controls. Critically however, the frequency range of altered connectivity was consistent across clinical syndromes that shared a likely underlying pathology, whilst the localization of changes differed between clinical syndromes. Multivariate pattern analysis of the frequency-specific topographies of local efficiency separated the disorders from each other and from controls (accuracy 62% to 100%, according to the groups' differences in likely pathology and clinical syndrome). The data indicate that magnetoencephalography has the potential to reveal specific changes in neurophysiology resulting from neurodegenerative disease. Our findings confirm that while clinical syndromes have characteristic anatomical patterns of abnormal connectivity that may be identified with other methods like structural brain imaging, the different mechanisms of neurodegeneration also cause characteristic spectral signatures of physiological coupling that are not accessible with structural imaging nor confounded by the neurovascular signalling of functional MRI. We suggest that these spectral characteristics of altered connectivity are the result of differential disruption of neuronal microstructure and synaptic physiology by Alzheimer's disease versus frontotemporal lobar degeneration.Peer reviewe