Visual Distraction: An Altered Aiming Spatial Response in Dementia

Background/Aims: Healthy individuals demonstrate leftward bias on visuospatial tasks such as line bisection, which has been attributed to right brain dominance. We investigated whether this asymmetry occurred in patients with probable dementia of the Alzheimer type (pAD) which is associated with neurodegenerative changes affecting temporoparietal regions. Methods: Subjects with pAD and matched controls performed a line bisection task in near and far space under conditions of no distraction, left-sided visual distraction and right-sided visual distraction. Results: Participants with pAD manifested different motor-preparatory ‘aiming’ spatial bias than matched controls. There were significantly greater rightward ‘aiming’ motor-intentional errors both without distraction and with right-sided distraction. Conclusion: ‘Aiming’ motor-preparatory brain activity may be induced by distraction in pAD subjects as compared to typical visual-motor function in controls

Factors associated with remission of post-traumatic brain injury fatigue in the years following traumatic brain injury (TBI): a TBI model systems module study

Post-traumatic brain injury fatigue (PTBIF) is a major problem in the years after traumatic brain injury (TBI), yet little is known about its persistence and resolution. The objective of the study was to identify factors related to PTBIF remission and resolution. TBI Model System registrants at five centres participated in interviews at either one and two years post-injury (Y1-2 Cohort), or two and five years post-injury (Y2-5 Cohort). Characteristics of participants with PTBIF remission were compared to those with PTBIF persistence. Variables studied included the presence of and changes in disability, sleep dysfunction, mood, and community participation. The Functional Independence Measure did not differ significantly between groups or over time. In the Y1-2 Cohort the Fatigue Resolved group scored significantly better on the Disability Rating Scale and Pittsburgh Sleep Quality Index. In the Y2-5 Cohort the Fatigue Resolved group scored significantly higher on a measure of community participation. It was concluded that fewer than half of the sample in each cohort experienced a remission of PTBIF between time points. Persistence of PTBIF 1–2 years post-injury is associated with disability, sleep disturbance, and depression while persistence of fatigue beyond 2 years post-injury appears to be related to participation level, underscoring the potential impact of effective surveillance, assessment, and treatment of this condition in optimising life after TBI. Differences in fatigue progression may point to the presence of different types of PTBIF

Race/Ethnicity and Retention in Traumatic Brain Injury Outcomes Research: A Traumatic Brain Injury Model Systems National Database Study

Objective: To investigate the contribution of race/ethnicity to retention in traumatic brain injury (TBI) research at 1 to 2 years post-injury. Setting: Community. Participants: 5548 Whites, 1347 Blacks, and 790 Hispanics enrolled in the Traumatic Brain Injury Model Systems National Database with dates of injury between October 1, 2002 and March 31, 2013. Design: Retrospective database analysis. Main Measure: Retention, defined as completion of at least one question on the follow-up interview by the person with TBI or a proxy. Results: Retention rates 1-2 years post-TBI were significantly lower for Hispanic (85.2%) than for White (91.8%) or Black participants (90.5%) and depended significantly on history of problem drug or alcohol use. Other variables associated with low retention included older age, lower education, violent cause of injury, and discharge to an institution versus private residence. Conclusions: The findings emphasize the importance of investigating retention rates separately for Blacks and Hispanics rather than combining them or grouping either with other races or ethnicities. The results also suggest the need for implementing procedures to increase retention of Hispanics in longitudinal TBI researc

Relationship Between Hispanic Nativity, Residential Environment, and Productive Activity Among Individuals With Traumatic Brain Injury: A TBI Model Systems Study

Objective: To examine the influence of nativity and residential characteristics on productive activity among Hispanics at 1 year after traumatic brain injury (TBI). Setting: Acute rehabilitation facilities and community follow-up. Participants: A total of 706 Hispanic individuals in the TBI Model Systems National Database. Design: Secondary data analysis from a multicenter longitudinal cohort study. Main Measures: Nativity (foreign born or US native), productive activity derived from interview questions regarding employment status, and other demographic information. Census data were extracted by zip code to represent residential characteristics of aggregate household income and proportion of foreign language speakers (FLS). Results: Among foreign-born individuals with TBI, those living in an area with a higher proportion of FLS were 2.8 times more likely to be productive than those living in areas with a lower proportion of FLS. Among individuals living in an area with a lower proportion of FLS, US-born Hispanics were 2.7 times more likely to be productive compared with Hispanic immigrants. Conclusion: The relationship between nativity and productive activity at 1 year post-TBI was moderated by the residential proportion of FLS. Findings underscore the importance of considering environmental factors when designing vocational rehabilitation interventions for Hispanics after TBI

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale