The Functional Field of View of Older Adults is Associated With Contrast Discrimination in the Magnocellular not Parvocellular Pathway.

OBJECTIVES: As we age, the functional field of view (FFOV) declines and these declines predict falls and motor vehicle accidents in older adults (Owsley, C. (2013). Visual processing speed. Vision Research, 90, 52-56. doi:10.1016/j.visres.2012.11.014). To increase understanding of possible causes of this decline, the current study explored whether the FFOV in older adults is associated with the sensitivity of the magnocellular and parvocellular sub-cortical pathways. METHOD: Forty-four younger (M = 27.18, SD = 5.40 years) and 44 older (M = 72.18, SD = 5.82 years) adults completed an FFOV test and the steady- and pulsed-pedestal paradigms of Pokorny and Smith (Pokorny, J., & Smith, V. C. (1997). Psychophysical signatures associated with magnocellular and parvocellular pathway contrast gain. Journal of the Optical Society of America. A, Optics, Image Science, and Vision, 14, 2477-2486. doi:10.1364/josaa.14.002477) as measures of magnocellular and parvocellular pathways, respectively. RESULTS: Older adults made more FFOV errors and had higher contrast discrimination thresholds in both the steady- and pulsed-pedestal paradigms, than younger adults. FFOV errors in the younger group were not related to contrast discrimination thresholds. In multiple regression, older group FFOV errors showed a strong unique association with contrast discrimination thresholds mediated via the magnocellular, but not the parvocellular pathway. DISCUSSION: We infer that reduced magnocellular pathway contrast sensitivity may contribute to reduced functional vision in older adults.

Tactical and strategic driving behaviour in older drivers: The importance of readiness to change.

The aim of this study was to explore the way in which reports of strategic and tactical driving self-regulation are influenced by readiness to change driving behaviour in older men and women, either reporting or not reporting modification of driving behaviour for health-related reasons, and/or increased driving difficulty. Current Australian drivers aged over 60 years (N = 258) responded to a self-report questionnaire. Hierarchical regression analyses indicated increased use of tactical behaviours were associated with greater driving difficulty, more readiness to change and male gender (R2 = 23.2%) . These effects were moderated by a significant association between readiness to change, driving modifications for health reasons and age (R2chg = 2.9%). Greater readiness to change was associated with increased use of tactical behaviours for older drivers who did not modify driving for health reasons, independent of ageIndependent of age. This association was also found for younger old drivers with health difficulties, but not for older old drivers with health difficulties. Hierarchical regression indicated that greater readiness to change, increased driving difficulty, female gender and modification of driving for health reasons were associated with reports of increased strategic self-regulation (R2 = 50.8%). These effects were moderated by readiness to change and age, and readiness to change and gender (R2chg = 2.1%). The association between readiness to change and strategic self-regulation was stronger for women than men, and the strength of this association became substantially stronger with increasing age. It was concluded that readiness to change driving behaviour may promote different forms of driving self-regulation for different individuals, and that older drivers may use the different forms of driving self-regulation independently of one another.

Perceived Parental Rearing in Paediatric Obsessive-Compulsive Disorder: Examining the Factor Structure of the EMBU Child and Parent Versions and Associations with OCD Symptoms.

Parental rearing behaviours characterised by high levels of rejection and overprotection have been implicated in the development and maintenance of child psychopathology, including paediatric obsessive-compulsive disorder (OCD). The Egna Minnen Beträffande Uppfostran (EMBU) is a commonly used measure of perceived parental rearing. Using confirmatory factor analysis, the factor structure of the EMBU child and parent versions were examined in a sample of children and youth with OCD (n = 176), and their mothers (n = 162). Associations between rearing and clinical correlates of OCD were explored. For parents, a 4-factor model provided the best fit. For children, a higher order model was the best fit. Greater parent and child perceived negative rearing behaviours and lower perceived positive behaviours were associated with greater OCD severity, comorbid symptoms and impairment. The EMBU has a conceptually meaningful factor structure and provides a useful measure for assessing perceived rearing behaviours within paediatric OCD.

Inflated Responsibility Beliefs in Paediatric OCD: Exploring the Role of Parental Rearing and Child Age.

Cognitive-behavioural models of obsessive-compulsive disorder (OCD) propose that inflated responsibility beliefs are central to the maintenance of the disorder and are proposed to originate during early childhood via experiences of harsh and/or controlling parenting. The current study aimed to examine the associations between perceived parental rearing behaviours, inflated responsibility/threat beliefs, and OCD severity and impairment in children (aged 7-12 years) and adolescents (aged 13-17 years) with OCD (n = 136). Results indicated that for younger children, greater child perceptions of overprotection and anxious rearing were each associated with increased inflated responsibility beliefs. For older children, these positive associations remained, and furthermore, inflated responsibility beliefs mediated the association between perceived maternal anxious rearing and OCD impairment. Results highlight the role of the family in the development of inflated responsibility bias and OCD-related impairment.

Relational thinking in later adulthood.

The research addressed the role of relational processing capacity in cognitive aging focusing on (a) age-differences in complex relational processing, (b) the domain-generality of complex relational processing, and (c) associations of complex relational processing with other processes. Participants were 125 adults in three groups with mean ages of 30.55 (younger), 53.43 (middle), and 74.41 years (older). Each relational processing task (sentence comprehension, n-term premise integration, Latin square) included items at three complexity levels. Accuracy was lower on more complex items and relational complexity had a greater effect in the older group. Confirmatory factor analyses confirmed a single complex relational processing factor, consistent with a domain-general capacity. Relational processing was related to other executive processes. This relationship was stronger in the older than younger and middle groups, possibly reflecting dedifferentiation or neural noise. In structural models with planning (Tower of London) and class reasoning as outcome variables, complex relational processing had a significant impact (ß = .455, p < .001 and ß = .661, p < .001, respectively) over and above age, processing speed, working memory, task switching, response inhibition, and Stroop interference. In the structural model with fluid intelligence (matrix reasoning) as the outcome variable, age had a significant impact (ß = -.222, p < .001), over and above all other variables, suggesting that the processes underpinning age-related declines in matrix reasoning are more diverse than those assessed in the current research. Complex relational processing is an important factor in cognitive aging, possibly reflecting its reliance on prefrontal brain regions. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

A Comparison of Two Chronic Skin Conditions: Atopic Dermatitis and Psoriasis.

Atopic dermatitis (eczema) and psoriasis are two common chronic skin diseases that affect many people, including active- duty military Servicemembers and their families. Both conditions have significant psychosocial impacts and can lead to substantial morbidity if undiagnosed and left untreated. We compare and contrast atopic dermatitis and psoriasis in terms of epidemiology, etiology, presentation, diagnosis, and treatment. The goal is to help military medical providers distinguish between the two diseases and provide practical steps for treatment and long-term management.

Identifying compensatory driving behavior among older adults using the situational avoidance questionnaire.

INTRODUCTION: Driving self-regulation is considered a means through which older drivers can compensate for perceived declines in driving skill or more general feelings of discomfort on the road. One form of driving self-regulation is situational avoidance, the purposeful avoidance of situations perceived as challenging or potentially hazardous. This study aimed to validate the Situational Avoidance Questionnaire (SAQ, Davis, Conlon, Ownsworth, & Morrissey, 2016) and identify the point on the scale at which drivers practicing compensatory avoidance behavior could be distinguished from those whose driving is unrestricted, or who are avoiding situations for other, non-compensatory reasons (e.g., time or convenience). METHOD: Seventy-nine Australian drivers (Mage=71.48, SD=7.16, range: 55 to 86years) completed the SAQ and were classified as a compensatory-restricted or a non-restricted driver based on a semi-structured interview designed to assess the motivations underlying avoidance behavior reported on the SAQ. RESULTS: Using receiver-operator characteristic (ROC) analysis, the SAQ was found to have high diagnostic accuracy (sensitivity: 85%, specificity: 82%) in correctly classifying the driver groups. Group comparisons confirmed that compensatory-restricted drivers were self-regulating their driving behavior to reduce the perceived demands of the driving task. This group had, on average, slower hazard perception reaction times, and reported greater difficulty with driving, more discomfort when driving due to difficulty with hazard perception skills, and greater changes in cognition over the past five years. CONCLUSIONS: The SAQ is a psychometrically sound measure of situational avoidance for drivers in baby boomer and older adult generations. PRACTICAL APPLICATIONS: Use of validated measures of driving self-regulation that distinguish between compensatory and non-compensatory behavior, such as the SAQ, will advance our understanding of the driving self-regulation construct and its potential safety benefits for older road users.

Bioluminescence imaging of G protein-coupled receptor activation in living mice.

G protein-coupled receptors (GPCRs), a superfamily of cell-surface receptors involved in virtually all physiological processes, are the major target class for approved drugs. Imaging GPCR activation in real time in living animals would provide a powerful way to study their role in biology and disease. Here, we describe a mouse model that enables the bioluminescent detection of GPCR activation in real time by utilizing the clinically important GPCR, sphingosine-1-phosphate receptor 1 (S1P1). A synthetic S1P1 signaling pathway, designed to report the interaction between S1P1 and ß-arrestin2 via the firefly split luciferase fragment complementation system, is genetically encoded in these mice. Upon receptor activation and subsequent ß-arrestin2 recruitment, an active luciferase enzyme complex is produced, which can be detected by in vivo bioluminescence imaging. This imaging strategy reveals the dynamics and spatial specificity of S1P1 activation in normal and pathophysiologic contexts in vivo and can be applied to other GPCRs.

The influence of age-related health difficulties and attitudes toward driving on driving self-regulation in the baby boomer and older adult generations.

Our study aimed to determine how age- and disease-related difficulties were associated with attitudes and beliefs about driving self-regulation in men and women in the baby boomer and older generations. Three hundred and ninety-nine men (n=204) and women (n=195) aged between 48 and 91 years participated in a cross-sectional study of Australian drivers. Demographic characteristics and measures of driving confidence, driving difficulty and driving self-regulation; perceptions of visual, physical and cognitive capacity; and attitudes and beliefs about driving were obtained. Driving self-regulation in men and women was explained by different mechanisms. For men, self-report of visual and cognitive difficulties and poor driving confidence predicted driving self-regulation. For women, negative attitudes toward driving mediated the associations found between health-related difficulties and driving self-regulation. Barriers to driving self-regulation were not associated with the driving self-regulatory practices of men or women. Regardless of generation, women reported poorer driving confidence, greater driving difficulty and more driving self-regulation than men. We concluded that age- and disease-related difficulties are related to increasing driving self-regulation in mature men and women. These results indicate that different pathways are needed in models of driving self-regulation for men and women regardless of generational cohort.

Perceptual processing deficits underlying reduced FFOV efficiency in older adults.

Older adults are known to perform more poorly on measures of the functional field of view (FFOV) than younger adults. Specific contributions by poor bottom-up and or top-down control of visual attention to the reduced FFOV of older adults were investigated. Error rates of older and younger adults were compared on a FFOV task in which a central identification task, peripheral localization task, and peripheral distractors were presented in high and low contrast. Older adults made more errors in all conditions. The effect of age was independent of the contrast of the peripheral target or distractors. The performance cost of including the central task was measured and found to be negligible for younger adults. For older adults performance costs were present in all conditions, greater with distractors than without, and greater for a low rather than high contrast central stimulus when the peripheral target was high contrast. These results are consistent with older adults compensating for reduced sensory input or bottom-up capture of attention by relying more heavily on top-down control for which they are resource limited.

The Impact of Older Age and Sex on Motion Discrimination.

Background/Study Context: Reports of age-related differences on motion discrimination tasks have produced inconsistent findings concerning the influence of sex. Some studies have reported that older women have higher thresholds than older men, with others finding that women have higher motion thresholds regardless of age group. Reports of the age at which declines in motion discrimination first occur also differ, with some studies reporting declines only in groups aged over 70 years, with others reporting that age-related decline occurs at a younger age. The current study aimed to determine whether the sex differences found occur because relative to men, women have greater difficulty extracting motion signals from noise (Experiment 1) or have greater difficulty making use of the available motion cues (Experiment 2) in these complex moving stimuli. In addition, the influence of these manipulations on groups aged under and over 70 years was explored. METHODS: Motion discrimination measures were obtained using 39 older adults aged between 60 and 85 years (21 women) and 40 younger adults aged between 20 and 45 years (20 women). In Experiment 1, coherent motion and relative motion displacement thresholds were obtained. In Experiment 2, coherent motion thresholds were obtained for stimuli containing either 150 or 600 dots. RESULTS: In Experiment 1, the older group had significantly higher thresholds on the relative motion displacement and coherent motion tasks than a younger group. No differences in motion sensitivity were found in the older groups aged under or over 70 years. Women regardless of age group had significantly higher thresholds than men on both tasks. In Experiment 2, the older group had higher coherence thresholds than the younger group, and the number of dots presented had no influence on thresholds, for the older group or older women specifically. In the younger group, women had higher coherence thresholds than men with presentation of 150 but not 600 dots. There were 51% of the older group who showed evidence of age-related decline on all the motion coherence tasks conducted, with half of these in each the group aged under and over 70 years. CONCLUSION: Difficulties with noise exclusion failed to explain the sex differences found. The increased number of motion cues present when a larger number of dots were included was sufficient to reduce coherence thresholds in younger women but not older men or women. In addition to age, developmental history and sex may provide further predictors in older individuals of decline on measures of motion discrimination.

Comorbidity in Emetophobia (Specific Phobia of Vomiting).

BACKGROUND: Emetophobia (fear of vomiting) is an anxiety disorder in which individuals report clinical levels of fear that they may vomit or be exposed to the vomit of others. The prevalence of comorbidity of emetophobia with other conditions has previously only been investigated using self-report instruments. METHOD: Sixty-four adults with emetophobia participated in an online structured clinical diagnostic interview assessing the presence of emetophobia and other conditions. RESULTS: Higher comorbidity for depression, generalized anxiety disorder, panic disorder, social anxiety disorder and obsessive-compulsive disorder were found in participants compared with general population norms. CONCLUSIONS: Emetophobia is commonly comorbid with other anxiety and depressive disorders. Comorbidity rates, when assessed using a structured clinical interview, were lower than previously reported using self-report alone. Copyright © 2015 John Wiley & Sons, Ltd. Key Practitioner Message Emetophobia (specific phobia of vomiting) is a clinical fear of vomiting. Individuals with emetophobia show high comorbidity with other anxiety and mood disorders. The most common comorbid conditions were generalized anxiety disorder, panic disorder, hypochondriasis and obsessive-compulsive disorder. Clinicians should ensure that they assess for the presence of comorbid conditions when treating emetophobia.

One session treatment for pediatric blood-injection-injury phobia: A controlled multiple baseline trial.

The present study evaluated the effectiveness of a modified One Session Treatment (OST), which included an e-therapy homework maintenance program over 4 weeks for Blood-Injection-Injury (BII) phobia in children and adolescents. Using a single case, non-concurrent multiple-baseline design, 24 children and adolescents (8-18 years; 7 males, 17 females) with a primary diagnosis of BII phobia were randomly assigned to a one, two or three week baseline prior to receiving OST. Primary outcome measures included diagnostic severity, diagnostic status, and child and parent fear ratings. Secondary outcome measures included avoidance during behavioural avoidance tasks (BAT), global functioning and self and parent reported anxiety, fear and depression. Efficacy was assessed at post-treatment, 1-month, and 3-month follow-up. BII symptoms and diagnostic severity remained relatively stable during the baseline periods and then significantly improved following implementation of the intervention. Treatment response was supported by changes across multiple measures, including child, parent and independent clinician ratings. At post-treatment 8 of the 24 (33.33%) children were BII diagnosis free. Treatment gains improved at follow-ups with 14 (58.33%) children diagnosis free at 1-month follow-up and 15 (62.5%) diagnosis free at 3-month follow-up. Preliminary findings support the effectiveness of a modified OST approach for BII phobic youth with treatment outcomes improving over follow-up intervals.

Do older individuals have difficulty processing motion or excluding noise? Implications for safe driving.

This study aimed to determine if difficulties extracting signal from noise explained poorer coherent motion thresholds in older individuals, particularly women. In four experimental conditions the contrast of the signal and noise dots used in a random dot kinematogram was manipulated. Coherence thresholds were highest when the signal dots were of a lower contrast than the noise dots and lowest when the signal dots were of a higher contrast than the noise dots. In all conditions the older group had higher coherence thresholds than the younger group, and women had higher thresholds than men. Significant correlations were found between coherence thresholds and self-reported driving difficulties in conditions in which the signal dots had to be extracted from noise only. The results indicate that older individuals have difficulties extracting signal from noise in cluttered visual environments. The implications for safe driving are discussed.

Why do adults with dyslexia have poor global motion sensitivity?

Two experiments aimed to determine why adults with dyslexia have higher global motion thresholds than typically reading controls. In Experiment 1, the dot density and number of animation frames presented in the dot stimulus were manipulated because of findings that use of a high dot density can normalize coherence thresholds in individuals with dyslexia. Dot densities were 14.15 and 3.54 dots/deg(2). These were presented for five (84 ms) or eight (134 ms) frames. The dyslexia group had higher coherence thresholds in all conditions than controls. However, in the high dot density, long duration condition, both reader groups had the lowest thresholds indicating normal temporal recruitment. These results indicated that the dyslexia group could sample the additional signals dots over space and then integrate these with the same efficiency as controls. In Experiment 2, we determined whether briefly presenting a fully coherent prime moving in either the same or opposite direction of motion to a partially coherent test stimulus would systematically increase and decrease global motion thresholds in the reader groups. When the direction of motion in the prime and test was the same, global motion thresholds increased for both reader groups. The increase in coherence thresholds was significantly greater for the dyslexia group. When the motion of the prime and test were presented in opposite directions, coherence thresholds were reduced in both groups. No group threshold differences were found. We concluded that the global motion processing deficit found in adults with dyslexia can be explained by undersampling of the target motion signals. This might occur because of difficulties directing attention to the relevant motion signals in the random dot pattern, and not a specific difficulty integrating global motion signals. These effects are most likely to occur in the group with dyslexia when more complex computational processes are required to process global motion.

The influence of contrast on coherent motion processing in dyslexia.

The aim of the experiments was to investigate how manipulating the contrast of the signal and noise dots in a random dot kinematogram (RDK), influenced on motion coherence thresholds in adults with dyslexia. In the first of two experiments, coherent motion thresholds were measured when the contrasts of the signal and noise dots in an RDK were manipulated. A significantly greater processing benefit was found for the group with dyslexia than a control group when the signal dots were of higher contrast than the noise dots. However, a significant processing disadvantage was found for the group with dyslexia relative to the control group when the signal dots were of lower contrast than the noise dots. These findings were interpreted as supporting evidence for the noise exclusion hypothesis of dyslexia. In Experiment 2, the effect on coherent motion thresholds of presenting a cue that alerted observers to which stimuli, high or low contrast contained the signals dots was investigated. When the cue directed attention to low contrast signal dots presented in high contrast noise, coherent motion thresholds were only enhanced for the group with dyslexia. This manipulation produced equivalent coherent motion thresholds in the reader groups. In other conditions, the group with dyslexia had significantly higher coherent motion thresholds than the control group. It was concluded that adults with dyslexia who show evidence of a coherent motion deficit (37% of the dyslexia group in each experiment), have a specific difficulty in noise exclusion. This appears to occur as consequence of a sensory processing deficit in the magnocellular or dorsal stream.

Visual search deficits are independent of magnocellular deficits in dyslexia.

The aim of this study was to investigate the theory that visual magnocellular deficits seen in groups with dyslexia are linked to reading via the mechanisms of visual attention. Visual attention was measured with a serial search task and magnocellular function with a coherent motion task. A large group of children with dyslexia (n = 70) had slower serial search times than a control group of typical readers. However, the effect size was small (η(p)(2) = 0.05) indicating considerable overlap between the groups. When the dyslexia sample was split into those with or without a magnocellular deficit, there was no difference in visual search reaction time between either group and controls. The data suggest that magnocellular sensitivity and visual spatial attention weaknesses are independent of one another. They also provide more evidence of heterogeneity in response to psychophysical tasks in groups with dyslexia. Alternative explanations for poor performance on visual attention tasks are proposed along with avenues for future research.

Does a sensory processing deficit explain counting accuracy on rapid visual sequencing tasks in adults with and without dyslexia?

The experiments conducted aimed to investigate whether reduced accuracy when counting stimuli presented in rapid temporal sequence in adults with dyslexia could be explained by a sensory processing deficit, a general slowing in processing speed or difficulties shifting attention between stimuli. To achieve these aims, the influence of the inter-stimulus interval (ISI), stimulus duration, and sequence length were evaluated in two experiments. In the first that used skilled readers only, significantly more errors were found with presentation of long sequences when the ISI or stimulus durations were short. Experiment 2 used a wider range of ISIs and stimulus durations. Compared to skilled readers, a group with dyslexia had reduced accuracy on two-stimulus sequences when the ISI was short, but not when the ISI was long. Although reduced accuracy was found on all short and long sequences by the group with dyslexia, when performance on two-stimulus sequences was used as an index of sensory processing efficiency and controlled, group differences were found with presentation of stimuli of short duration only. We concluded that continuous, repetitive stimulation to the same visual area can produce a capacity limitation on rapid counting tasks in all readers when the ISIs or stimulus durations are short. While reduced accuracy on rapid sequential counting tasks can be explained by a sensory processing deficit when the stimulus duration is long, slower processing speed in the group with dyslexia explains the greater inaccuracy found as sequence length is increased when the stimulus duration is short.

Auditory and visual processing in children with dyslexia.

This study investigated the temporal stability and longitudinal replicability of visual and auditory sensory processes found to be poor in children with dyslexia. Seventy children with dyslexia and 52 normal readers were tested twice, 9 months apart, on measures of visual and auditory sensory processing and on phonological and orthographic skills. About 30% of children with dyslexia were found to have sensory deficits. Associations were found between sensory and cognitive skills. Based on analyses of agreement, the temporal stability of the sensory tasks was poor. Future research should develop sensory measures with high temporal stability that can control for maturation.

Relationships between global motion and global form processing, practice, cognitive and visual processing in adults with dyslexia or visual discomfort.

The aim of the first of two experiments was to investigate the effect of practice on sensitivity to global motion and global form in a group of adults with dyslexia, a group of normal readers with visual discomfort, a group with dyslexia and visual discomfort, and a control group. In comparison to the control group, and regardless of the effect of practice, the group with dyslexia was significantly less sensitive to global motion. No differences in global motion sensitivity were found when individuals with dyslexia, with or without visual discomfort, were compared. The normal reading group with visual discomfort was less sensitive to global motion than the control group at baseline, but not when a second estimate of motion sensitivity was obtained. About 30% of the group with dyslexia had a global motion deficit on each threshold estimate. In contrast, there were no significant effects of practice or group on sensitivity to global form. In Experiment 2, performance on a number of cognitive and visual processing tasks was measured in four groups: two with dyslexia; one with and one without a global motion deficit, a normal reading group with visual discomfort, and a control group. The group with visual discomfort had reduced visual processing speed only. Regardless of whether a global motion processing deficit was present or absent in individuals with dyslexia, reduced accuracy was found on the language and visual processing measures, and on a rapid temporal sequencing task. Individuals with dyslexia and a global motion deficit had poorer accuracy than individuals with dyslexia and no motion deficit on the phonological processing and verbal short term memory tasks. We concluded that some adults with dyslexia have a persistent deficit when processing global motion but not global form. This is consistent with reports of a magnocellular pathway deficit in this group. Individuals with visual discomfort do not have a magnocellular processing deficit, but have perceptual difficulties when performing complex visual processing tasks.