A longitudinal analysis of factors associated with post traumatic growth after acquired brain injury.

ABSTRACTPost-Traumatic Growth (PTG) is a form of positive psychological change that occurs for some individuals following traumatic experiences. High levels of PTG have been reported among survivors of acquired brain injury (ABI). Yet it remains unclear why some survivors of ABI develop PTG and others do not. The present study investigated early and late factors that are associated with long-term PTG in people with moderate to severe ABIs. Participants (n = 32, Mage = 50.59, SD = 12.28) completed self-report outcome measures at two time-points seven years apart (one-year and eight-years post-ABI). Outcome measures assessed emotional distress, coping, quality of life and ongoing symptoms of brain injury, as well as PTG at the later timepoint. Multiple regression analyses indicated that one-year post-ABI, fewer symptoms of depression, more symptoms of anxiety, and use of adaptive coping strategies accounted for a significant amount of variance in later PTG. At eight years post-ABI, fewer symptoms of depression, fewer ongoing symptoms of brain injury, better psychological quality of life and use of adaptive coping strategies explained a substantial amount of variance in PTG. For individuals with ABIs, PTG may be promoted by implementing long-term neuropsychological support which aims to facilitate use of adaptive coping strategies, supports psychological wellbeing and allows individuals to find meaning post-ABI.

Self-reported outcomes and patterns of service engagement after an acquired brain injury: a long-term follow-up study.

PRIMARY OBJECTIVE: To describe the clinical characteristics, self-reported outcomes in domains relating to activities of daily living and patterns of service engagement in the survivors of a moderate-to-severe acquired brain injury over seven years. RESEARCH DESIGN: A longitudinal research design was used. METHODS AND PROCEDURES: Thirty-two individuals who sustained a moderate-to-severe acquired brain injury completed a Sociodemographic and Support Questionnaire at one (t1) and seven years (t2) after completing a publicly funded inpatient neurorehabilitation program. MAIN OUTCOMES AND RESULTS: There were minimal changes in independent living, mobility, ability to maintain key relationships and in return to work in the interval between t1 and t2. Sixty-nine percent of participants engaged with two or more allied health professional services and 75% engaged with support services in the community over the seven years. CONCLUSIONS: There were minimal additional gains in outcomes relating to activities of daily-living and there was a high level of service need in the first decade postinjury. Young and middle-aged individuals who sustain an ABI may continue to live in the community for decades with some level of disability and may require ongoing access to services.

Validation of Raised Cord Blood Interleukin-16 in Perinatal Asphyxia and Neonatal Hypoxic-Ischaemic Encephalopathy in the BiHiVE2 Cohort.

The role of inflammation is an important factor in the progression of hypoxic-ischaemic encephalopathy (HIE). We have previously shown that interleukin-16 (IL-16) is increased in infants with moderate and severe HIE and relates to poor neurodevelopmental outcomes. We aimed to validate IL-16 as a cord blood-based biomarker for HIE and to examine its relationship to long-term outcomes. The study sample consisted of 105 full-term infants who experienced perinatal asphyxia (PA) (with and without an encephalopathy) along with healthy, gestational age-matched newborn controls. Umbilical cord blood serum was processed and biobanked at delivery. Infants were assigned a modified Sarnat score at 24 h. Analysis of IL-16 cytokine cord blood levels was performed using the sandwich-based enzyme-linked immunosorbent assay (ELISA) technique. Cord blood-based IL-16 was increased in infants with PA and HIE relative to controls (p = 0.025). IL-16 was also increased in the HIE group relative to controls (p = 0.042). There was no significant difference in IL-16 across grades of HIE or in those with abnormal outcomes at 2 years of age. This study validates findings that cord blood-based IL-16 levels are increased in infants with PA, including those who go on to develop HIE.

Feasibility of using touch screen technology for early cognitive assessment in children.

OBJECTIVE: To explore the feasibility of using a touch screen assessment tool to measure cognitive capacity in toddlers. DESIGN: 112 typically developing children with a median age of 31 months (IQR: 26-34) interacted with a touch screen cognitive assessment tool. We examined the sensitivity of the tool to age-related changes in cognition by comparing the number of items completed, speed of task completion and accuracy in two age groups; 24-29 months versus 30-36 months. RESULTS: Children aged 30-36 months completed more tasks (median: 18, IQR: 18-18) than those aged 24-29 months (median: 17, IQR: 15-18). Older children also completed two of the three working memory tasks and an object permanence task faster than their younger peers. Children became faster at completing the working memory items with each exposure and registered similar completion times on the hidden object retrieval items, despite task demands being twofold on the second exposure. A novel item required children to integrate what they had learnt on preceding items. The older group was more likely to complete this item and to do so faster than the younger group. CONCLUSIONS: Children as young as 24 months can complete items requiring cognitive engagement on a touch screen device, with no verbal instruction and minimal child-administrator interaction. This paves the way for using touch screen technology for language and administrator independent developmental assessment in toddlers.

Abstract and Effector-Selective Decision Signals Exhibit Qualitatively Distinct Dynamics before Delayed Perceptual Reports.

UNLABELLED: Electrophysiological research has isolated neural signatures of decision formation in a variety of brain regions. Studies in rodents and monkeys have focused primarily on effector-selective signals that translate the emerging decision into a specific motor plan, but, more recently, research on the human brain has identified an abstract signature of evidence accumulation that does not appear to play any direct role in action preparation. The functional dissociations between these distinct signal types have only begun to be characterized, and their dynamics during decisions with deferred actions with or without foreknowledge of stimulus-effector mapping, a commonly studied task scenario in single-unit and functional imaging investigations, have not been established. Here we traced the dynamics of distinct abstract and effector-selective decision signals in the form of the broad-band centro-parietal positivity (CPP) and limb-selective ß-band (8-16 and 18-30 Hz) EEG activity, respectively, during delayed-reported motion direction decisions with and without foreknowledge of direction-response mapping. With foreknowledge, the CPP and ß-band signals exhibited a similar gradual build-up following evidence onset, but whereas choice-predictive ß-band activity persisted up until the delayed response, the CPP dropped toward baseline after peaking. Without foreknowledge, the CPP exhibited identical dynamics, whereas choice-selective ß-band activity was eliminated. These findings highlight qualitative functional distinctions between effector-selective and abstract decision signals and are of relevance to the assumptions founding functional neuroimaging investigations of decision-making. SIGNIFICANCE STATEMENT: Neural signatures of evidence accumulation have been isolated in numerous brain regions. Although animal neurophysiology has largely concentrated on effector-selective decision signals that translate the emerging decision into a specific motor plan, recent research on the human brain has isolated abstract neural signatures of decision formation that are independent of specific sensory and motor requirements. Here, we examine the functional distinctions between the two distinct classes of decision variable signal during decisions with deferred actions with and without foreknowledge of stimulus-effector mapping. We find salient distinctions in the dynamics of abstract versus effector-selective decision signals in the human brain, in terms of sustainment through response delays and contingency on foreknowledge of stimulus-response mapping.

The classic P300 encodes a build-to-threshold decision variable.

The P300 component of the human event-related potential has been the subject of intensive experimental investigation across a five-decade period, owing to its apparent relevance to a wide range of cognitive functions and its sensitivity to numerous brain disorders, yet its exact contribution to cognition remains unresolved. Here, we carry out key analyses of the P300 elicited by transient auditory and visual targets to examine its potential role as a 'decision variable' signal that accumulates evidence to a decision bound. Consistent with the latter, we find that the P300 reaches a stereotyped amplitude immediately prior to response execution and that its rate of rise scales with target detection difficulty and accounts for trial-to-trial variance in RT. Computational simulations of an accumulation-to-bound decision process faithfully captured P300 dynamics when its parameters were set by model fits to the RT distributions. Thus, where the dominant explanatory accounts have conceived of the P300 as a unitary neural event, our data reveal it to be a dynamically evolving neural signature of decision formation. These findings place the P300 at the heart of a mechanistically principled framework for understanding decision-making in both the typical and atypical human brain.