Michelle Keightley

Distributed self in episodic memory: neural correlates of successful retrieval of self-encoded positive and negative personality traits

Words processed with reference to the self are generally better remembered than words processed in semantic terms. An account of this phenomenon, labeled the Self Reference Effect (SRE), is that the self promotes elaboration and organization of encoded information. Although a few neuroimaging studies associated self-referential encoding with activations of the medial prefrontal cortex, no previous study has investigated the neural correlates of remembering emotional words encoded in an SRE paradigm. The main goal of this study was to define with fMRI the neural correlates of the successful retrieval of negative and positive personality traits encoded in a self-referential mode. Functional MRI scans were acquired for 11 subjects as they recognized positive and negative emotional personality traits adjectives encoded in a self-referential condition, a semantic condition and in a phonemic condition. The correct recognition of self-encoded personality traits engaged dorso-medial prefrontal cortex and lateral prefrontal regions, premotor cortex, parietal and occipital cortex, caudate and cerebellum. The specific recognition of self-encoded negative personality traits involved greater neural activation in the right extra-striate region than the recognition of positive personality traits. Our fMRI findings suggest that specific processes may operate at both encoding and retrieval to subserve the SRE. Unlike self-encoding, the retrieval of personality traits is modulated by the valence of the stimuli with greater activation for negative words. Our results indicate that personally relevant words may signal important emotional clues and support the notion of a widely distributed set of brain regions involved in maintaining the concepts of self.

Age effects on social cognition : faces tell a different story

The authors administered social cognition tasks to younger and older adults to investigate age-related differences in social and emotional processing. Although slower, older adults were as accurate as younger adults in identifying the emotional valence (i.e., positive, negative, or neutral) of facial expressions. However, the age difference in reaction time was largest for negative faces. Older adults were significantly less accurate at identifying specific facial expressions of fear and sadness. No age differences specific to social function were found on tasks of self-reference, identifying emotional words, or theory of mind. Performance on the social tasks in older adults was independent of performance on general cognitive tasks (e.g., working memory) but was related to personality traits and emotional awareness. Older adults also showed more intercorrelations among the social tasks than did the younger adults. These findings suggest that age differences in social cognition are limited to the processing of facial emotion. Nevertheless, with age there appears to be increasing reliance on a common resource to perform social tasks, but one that is not shared with other cognitive domains.

Clinical Risk Score for Persistent Postconcussion Symptoms Among Children With Acute Concussion in the ED

IMPORTANCE Approximately one-third of children experiencing acute concussion experience ongoing somatic, cognitive, and psychological or behavioral symptoms, referred to as persistent postconcussion symptoms (PPCS). However, validated and pragmatic tools enabling clinicians to identify patients at risk for PPCS do not exist. OBJECTIVE To derive and validate a clinical risk score for PPCS among children presenting to the emergency department. DESIGN, SETTING, AND PARTICIPANTS Prospective, multicenter cohort study (Predicting and Preventing Postconcussive Problems in Pediatrics [5P]) enrolled young patients (aged 5-<18 years) who presented within 48 hours of an acute head injury at 1 of 9 pediatric emergency departments within the Pediatric Emergency Research Canada (PERC) network from August 2013 through September 2014 (derivation cohort) and from October 2014 through June 2015 (validation cohort). Participants completed follow-up 28 days after the injury. EXPOSURES All eligible patients had concussions consistent with the Zurich consensus diagnostic criteria. MAIN OUTCOMES AND MEASURES The primary outcome was PPCS risk score at 28 days, which was defined as 3 or more new or worsening symptoms using the patient-reported Postconcussion Symptom Inventory compared with recalled state of being prior to the injury. RESULTS In total, 3063 patients (median age, 12.0 years [interquartile range, 9.2-14.6 years]; 1205 [39.3%] girls) were enrolled (n = 2006 in the derivation cohort; n = 1057 in the validation cohort) and 2584 of whom (n = 1701 [85%] in the derivation cohort; n = 883 [84%] in the validation cohort) completed follow-up at 28 days after the injury. Persistent postconcussion symptoms were present in 801 patients (31.0%) (n = 510 [30.0%] in the derivation cohort and n = 291 [33.0%] in the validation cohort). The 12-point PPCS risk score model for the derivation cohort included the variables of female sex, age of 13 years or older, physician-diagnosed migraine history, prior concussion with symptoms lasting longer than 1 week, headache, sensitivity to noise, fatigue, answering questions slowly, and 4 or more errors on the Balance Error Scoring System tandem stance. The area under the curve was 0.71 (95% CI, 0.69-0.74) for the derivation cohort and 0.68 (95% CI, 0.65-0.72) for the validation cohort. CONCLUSIONS AND RELEVANCE A clinical risk score developed among children presenting to the emergency department with concussion and head injury within the previous 48 hours had modest discrimination to stratify PPCS risk at 28 days. Before this score is adopted in clinical practice, further research is needed for external validation, assessment of accuracy in an office setting, and determination of clinical utility.

Studies of altered social cognition in neuropsychiatric disorders using functional neuroimaging

In this paper, we review studies using functional neuroimaging to examine cognition in neuropsychiatric disorders. The focus is on social cognition, which is a topic that has received increasing attention over the past few years. A network of brain regions is proposed for social cognition that includes regions involved in processes relevant to social functioning (for example, self reference and emotion). We discuss the alterations of activity in these areas in patients with autism, depression, schizophrenia, and posttraumatic stress disorder in relation to deficits in social behaviour and symptoms. The evidence to date suggests that there may be some specificity of the brain regions involved in these 4 disorders, but all are associated with dysfunction in the amygdala and dorsal cingulate gyrus. Although there is much work remaining in this area, we are beginning to understand the complex interactions of brain function and behaviour that lead to disruptions of social abilities.

Personality influences limbic-cortical interactions during sad mood induction

The current study examined limbic-cortical activation under transient emotional stress as a function of personality style. A ventral cingulate (Cg25)-centred limbic-cortical network was identified using positron emission tomography (PET) measures of regional cerebral blood flow (rCBF) during a sad mood challenge that demonstrated differences for individuals selected for specific patterns of Negative and Positive emotional traits, indexed by the NEO Personality Inventory-Revised. Healthy subjects scoring both low on the dispositional Depression facet of Neuroticism (N3) and high on the Positive Emotions facet of Extraversion (E6) were compared to those scoring high on the Depression facet (N3) and low on Positive Emotions (E6), a combination of traits previously linked to normal variations in mood reactivity. Scan analyses were designed to further characterize known variations in Cg25 activity previously reported in studies of negative mood in both healthy subjects and depressed patients. A multivariate technique, partial least squares (PLS) demonstrated a divergent Cg25-mediated network that differentiated temperamentally negative (NAS) from temperamentally positive (PAS) subjects providing a potential neural link between these specific combinations of trait affective styles and vulnerability to depression.

The effect of age on memory for emotional faces.

Prior studies of emotion suggest that young adults should have enhanced memory for negative faces and that this enhancement should be reduced in older adults. Several studies have not shown these effects but were conducted with procedures different from those used with other emotional stimuli. In this study, researchers examined age differences in recognition of faces with emotional or neutral expressions, using trial-unique stimuli, as is typically done with other types of emotional stimuli. They also assessed the influence of personality traits and mood on memory. Enhanced recognition for negative faces was found in young adults but not in older adults. Recognition of faces was not influenced by mood or personality traits in young adults, but lower levels of extraversion and better emotional sensitivity predicted better negative face memory in older adults. These results suggest that negative expressions enhance memory for faces in young adults, as negative valence enhances memory for words and scenes. This enhancement is absent in older adults, but memory for emotional faces is modulated in older adults by personality traits that are relevant to emotional processing.

Sensory Processing and Adaptive Behavior Deficits of Children Across the Fetal Alcohol Spectrum Disorder Continuum

BACKGROUND Prenatal alcohol exposure can have detrimental effects on a childs development of adaptive behaviors necessary for success in the areas of academic achievement, socialization, and self-care. Sensory processing abilities have been found to affect a childs ability to successfully perform adaptive behaviors. The current study explored whether significant differences in sensory processing abilities, adaptive behavior, and neurocognitive functioning are observed between children diagnosed with partial Fetal Alcohol Syndrome (pFAS), Alcohol-Related Neurodevelopmental Disorder (ARND), or children who were prenatally exposed to alcohol (PEA), but did not meet criteria for an FASD diagnosis. The influence of IQ on adaptive behavior as well as further exploration of the relationship between sensory processing and adaptive behavior deficits among these children was also examined. METHODS A secondary analysis was conducted on some of the Short Sensory Profile (SSP) scores, Adaptive Behavior Assessment System--Second Edition (ABAS-II) scores, and Wechsler Intelligence Scale--Fourth Edition/Wechsler Preschool and Primary Scale of Intelligence--Third Edition (WISC- IV/WPPSI-III) scores of 46 children between 3 and 14 years of age with pFAS, ARND, or who were PEA. RESULTS Greater sensory processing deficits were found in children with a diagnosis of pFAS and ARND compared to those in the PEA group. Children with an ARND diagnosis scored significantly worse on measures of adaptive behavior than the PEA group. Children with pFAS scored significantly lower than children with ARND or PEA on perceptual/performance IQ. No correlation was found between IQ scores and adaptive behaviors across the FASD diagnostic categories. A significant positive correlation was found between SSP and ABAS-II scores. CONCLUSIONS Regardless of the diagnosis received under the FASD umbrella, functional difficulties that could not be observed using traditional measures of intelligence were found, supporting guidelines that a broad range of standardized assessments be included when screening children for FASD.

After the crash: Research-based theater for knowledge transfer

Introduction: The aim of this project was to develop and evaluate a research‐based dramatic production for the purpose of transferring knowledge about traumatic brain injury (TBI) to health care professionals, managers, and decision makers. Methods: Using results drawn from six focus group discussions with key stakeholders (consumers, informal caregivers, and health care practitioners experienced in the field of TBI) and relevant scientific literature, a 50‐minute play was produced for the purpose of conveying the experiences of TBI survivors, informal care providers, and health practitioners and best practice for TBI care. A self‐administered postperformance survey was distributed to audience members at the end of four performances in Ontario, Canada, to evaluate the plays efficacy. Two hundred ninety‐one questionnaires were completed. The questionnaire had five questions scored on a 5‐item Likert scale with space for open‐ended comments. Results: Consistently high mean scores from the questionnaires indicate that theater is a highly efficacious and engaging method of knowledge transfer, particularly for complex material that deals with human emotion and interpersonal relationships. Discussion: Responses supported the effectiveness of drama as a knowledge translation strategy and identified its potential to impact practice positively.

Systematic Review of the Clinical Course, Natural History, and Prognosis for Pediatric Mild Traumatic Brain Injury : Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis

OBJECTIVE To synthesize the best available evidence on prognosis after pediatric mild traumatic brain injury (MTBI). DATA SOURCES We searched MEDLINE, Embase, PsycINFO, CINAHL, and SPORTDiscus (2001-2012), as well as reference lists of eligible articles, and relevant systematic reviews and meta-analyses. STUDY SELECTION Controlled trials and cohort and case-control studies were selected according to predefined criteria. Studies had to have a minimum of 30 MTBI pediatric cases. After 77,914 records were screened for the entire review, 299 studies were eligible and assessed for scientific rigor. DATA EXTRACTION Eligible studies were critically appraised using the Scottish Intercollegiate Guidelines Network (SIGN) criteria. Two reviewers independently reviewed each study and extracted data from accepted articles into evidence tables. DATA SYNTHESIS Evidence from 25 accepted articles was synthesized qualitatively according to SIGN criteria, and prognostic information was prioritized according to design as exploratory or confirmatory. Most studies show that postconcussion symptoms and cognitive deficits resolve over time. Limited evidence suggests that postconcussion symptoms may persist in those with lower cognitive ability and intracranial pathology on neuroimaging. Preliminary evidence suggests that the risk of epilepsy is increased for up to 10 years after MTBI; however, there is insufficient high-quality evidence at this time to support this link. CONCLUSIONS Common post-MTBI symptoms and deficits in children are not specific to MTBI and appear to resolve with time; however, limited evidence suggests that children with intracranial pathology on imaging may experience persisting symptoms or deficits. Well-designed, long-term studies are needed to confirm these findings.

Age-related differences in brain activity underlying identification of emotional expressions in faces

We used fMRI to explore brain activity in young and old adults, while they viewed and labeled faces expressing different emotions as well as neutral expressions. Older adults had significantly greater difficulty identifying expressions of sadness, anger and disgust than young adults. Both groups performed at ceiling for happy expressions. The functional neuroimaging data revealed that both young and old adults recruited a pattern of activity that distinguished happy expressions from all other expressions, but the patterns were age-specific. Older adults showed increased activity in ventromedial prefrontal cortex, lingual gyrus and premotor cortex for happy expressions, whereas younger adults recruited a more widely distributed set of regions including the amgydala, ventromedial prefrontal cortex, lateral prefrontal regions and bilateral inferior parietal and superior temporal areas. Conversely, younger adults showed more activity in the dorsal anterior cingulate for other types of expressions, and older adults had more activity in dorsal cingulate, as well as middle and inferior frontal gyri, somatosensory cortex, insula and middle temporal regions. These results support previous research demonstrating age differences in brain activity during emotional processing, and suggest possible age-related differences in cognitive strategy during identification of happy faces, despite no effect of age on this ability.