Executive Function Profiles in Pediatric Traumatic Brain Injury.

Traumatic brain injury (TBI) results in heterogeneous patterns of neuropsychological impairment. This study investigated heterogeneity in executive function (EF) using the Comprehensive Trail Making Test (CTMT) to evaluate 121 children and adolescents with TBI and 121 matched normal controls. The TBI group performed approximately two standard deviations below controls. Cluster analyses indicated that a three-cluster solution best classified the TBI group and a four-cluster solution best classified controls. Greater impairment in EF was associated with lower intellectual, achievement, and neuropsychological test performance in the TBI group. Results suggest that EF deficits reflected in CTMT performance may be useful for classifying severity of TBI.

A cure is possible: a study of 10-year survivors of brain metastases.

Little is known on the natural history, recurrence patterns, neurocognitive outcomes and prognostic factors associated with survival in long-term survivors (≥10 years) from brain metastasis (BM). In this study, the records of 1953 patients who underwent treatment for BM with a potential for ≥10 years of follow-up were reviewed. Cox regression analysis identified factors predictive for overall survival (OS). The median age at brain metastasis diagnosis was 60 years and the median OS was 6.4 months. The 1-year OS rate was 29.9, 12.1 % at 2 years, 3.0 % at 5 years, and 1.3 % at 10 years. On multivariable analysis, factors associated with worse OS included gender (males, HR 1.2), multiple brain metastases (HR 1.3), no surgery (HR 1.8), and no stereotactic radiosurgery (HR 1.8) (p < 0.0001 each). Fifty-six patients (2.9 %) survived ≥5 years; 23 patients (1.2 %) survived ≥10 years and the median survival for ≥10 year survivors was 18.5 years. Six of the 10-year survivors had an intracranial recurrence, five occurred within 11 years from the first treatment. Presence of a solitary lesion or single lesion at the time of brain metastasis diagnosis was associated with improved survival. Eight of the ≥10 year survivors (34.8 %) had no neurological symptoms at last follow-up; none of the 10-year survivors were documented to have a neurologic death. Our study demonstrates that patients with favorable prognostic features should undergo multimodality treatment. Albeit rare, patients who are alive 10 years after treatment for their brain metastases may be considered cured from their intracranial disease.

Negative symptoms in bipolar disorder and schizophrenia: A psychometric evaluation of the brief negative symptom scale across diagnostic categories.

Past studies have demonstrated that the Brief Negative Symptom Scale (BNSS) has excellent psychometric properties in patients with schizophrenia. In the current study, we extended this literature by examining psychometric properties of the BNSS in outpatients diagnosed with bipolar disorder (n=46), outpatients with schizophrenia (n=50), and healthy controls (n=27). Participants completed neuropsychological testing and a clinical interview designed to assess negative, positive, disorganized, mood, and general psychiatric symptoms. Results indicated differences among the 3 groups in the severity of all BNSS items, with SZ and BD scoring higher than CN; however, SZ and BD only differed on blunted affect and alogia items, not anhedonia, avolition, or asociality. BD patients with a history of psychosis did not differ from those without a history of psychosis on negative symptom severity. The BNSS had excellent internal consistency in SZ, BD, and CN groups. Good convergent and discriminant validity was apparent in SZ and BD groups, as indicated by relationships between the BNSS and other clinical rating scales. These findings support the validity of the BNSS in broadly defined serious mental illness populations.

Concurrent sound segregation impairments in schizophrenia: The contribution of auditory-specific and general cognitive factors.

The present study sought to test whether perceptual segregation of concurrently played sounds is impaired in schizophrenia (SZ), whether impairment in sound segregation predicts difficulties with a real-world speech-in-noise task, and whether auditory-specific or general cognitive processing accounts for sound segregation problems. Participants with SZ and healthy controls (HCs) performed a mistuned harmonic segregation task during recording of event-related potentials (ERPs). Participants also performed a brief speech-in-noise task. Participants with SZ showed deficits in the mistuned harmonic task and the speech-in-noise task, compared to HCs. No deficit in SZ was found in the ERP component related to mistuned harmonic segregation at around 150ms (the object-related negativity or ORN), but instead showed a deficit in processing at around 400ms (the P4 response). However, regression analyses showed that indexes of education level and general cognitive function were the best predictors of sound segregation difficulties, suggesting non-auditory specific causes of concurrent sound segregation problems in SZ.

Predicting psychosis across diagnostic boundaries: Behavioral and computational modeling evidence for impaired reinforcement learning in schizophrenia and bipolar disorder with a history of psychosis.

There is increasing evidence that schizophrenia (SZ) and bipolar disorder (BD) share a number of cognitive, neurobiological, and genetic markers. Shared features may be most prevalent among SZ and BD with a history of psychosis. This study extended this literature by examining reinforcement learning (RL) performance in individuals with SZ (n = 29), BD with a history of psychosis (BD+; n = 24), BD without a history of psychosis (BD-; n = 23), and healthy controls (HC; n = 24). RL was assessed through a probabilistic stimulus selection task with acquisition and test phases. Computational modeling evaluated competing accounts of the data. Each participant's trial-by-trial decision-making behavior was fit to 3 computational models of RL: (a) a standard actor-critic model simulating pure basal ganglia-dependent learning, (b) a pure Q-learning model simulating action selection as a function of learned expected reward value, and (c) a hybrid model where an actor-critic is "augmented" by a Q-learning component, meant to capture the top-down influence of orbitofrontal cortex value representations on the striatum. The SZ group demonstrated greater reinforcement learning impairments at acquisition and test phases than the BD+, BD-, and HC groups. The BD+ and BD- groups displayed comparable performance at acquisition and test phases. Collapsing across diagnostic categories, greater severity of current psychosis was associated with poorer acquisition of the most rewarding stimuli as well as poor go/no-go learning at test. Model fits revealed that reinforcement learning in SZ was best characterized by a pure actor-critic model where learning is driven by prediction error signaling alone. In contrast, BD-, BD+, and HC were best fit by a hybrid model where prediction errors are influenced by top-down expected value representations that guide decision making. These findings suggest that abnormalities in the reward system are more prominent in SZ than BD; however, current psychotic symptoms may be associated with reinforcement learning deficits regardless of a Diagnostic and Statistical Manual of Mental Disorders (5th Edition; American Psychiatric Association, 2013) diagnosis.

Radiographic skeletal survey for non-accidental injury: systematic review and development of a national New Zealand protocol.

INTRODUCTION: Clinically occult fractures from non-accidental injury (NAI) are best detected on radiographic skeletal survey. However, there are regional variations regarding the views included in such surveys. We undertook a systematic review of the evidence supporting skeletal survey protocols to design a protocol that could be implemented across New Zealand. METHODS: In June 2013, we searched Medline, Google Scholar, the Cochrane database, UpToDate and relevant reference lists for English-language publications on skeletal survey in NAI from 1946. We included publications that contained a protocol or reported evidence supporting including, or excluding, specific views in a skeletal survey. All included publications were critically appraised. Based on this systematic review, a draft protocol was developed and presented to an Australian and New Zealand Society for Paediatric Radiology NAI symposium in October 2013. Feedback from the symposium and later discussions was incorporated into the final protocol. RESULTS: We identified 2 guidelines for skeletal survey, 13 other protocols and 15 articles providing evidence for inclusion of specific images in a skeletal survey. The guidelines scored poorly on critical appraisal of several aspects of their methods. We found no studies that validate any of the protocols or compare their performance. Evidence supporting inclusion in a skeletal survey is limited to ribs, spine, pelvis, hands and feet, and long bone views. Our final protocol is a standardised, two-tiered protocol consisting of between 17 and 22 views. CONCLUSION: A standardised protocol for radiographic skeletal survey protocol has been developed in New Zealand. We present it here for consideration by others.

Preliminary evidence for reduced auditory lateral suppression in schizophrenia.

BACKGROUND: Well-documented auditory processing deficits such as impaired frequency discrimination and reduced suppression of auditory brain responses in schizophrenia (SZ) may contribute to abnormal auditory functioning in everyday life. Lateral suppression of non-stimulated neurons by stimulated neurons has not been extensively assessed in SZ and likely plays an important role in precise encoding of sounds. Therefore, this study evaluated whether lateral suppression of activity in auditory cortex is impaired in SZ. METHODS: SZ participants and control participants watched a silent movie with subtitles while listening to trials composed of a 0.5s control stimulus (CS), a 3s filtered masking noise (FN), and a 0.5s test stimulus (TS). The CS and TS were identical on each trial and had energy corresponding to the high energy (recurrent suppression) or low energy (lateral suppression) portions of the FN. Event-related potentials were recorded and suppression was measured as the amplitude change between CS and TS. RESULTS: Peak amplitudes of the auditory P2 component (160-260ms) showed reduced lateral but not recurrent suppression in SZ participants. CONCLUSIONS: Reduced lateral suppression in SZ participants may lead to overlap of neuronal populations representing different auditory stimuli. Such imprecise neural representations may contribute to the difficulties SZ participants have in discriminating complex stimuli in everyday life.

Concordance of the Montreal cognitive assessment with standard neuropsychological measures.

INTRODUCTION: The concordance of the Montreal cognitive assessment (MoCA) with more comprehensive neuropsychological measures remains unclear. This study examined the individual MoCA domains with more comprehensive and commonly used neuropsychological measures to determine the degree of overlap. METHODS: Data included individuals seen in an outpatient neurology clinic specializing in neurodegenerative disease who were administered the MoCA and also underwent neuropsychological assessment (n = 471). A principal component analysis with varimax rotation was completed using the MoCA domain scores and comprehensive neuropsychological evaluation measures. RESULTS: Four factors emerged accounting for 55.6% of the variance: (1) visuospatial/executive functioning; (2) memory; (3) attention; and (4) language. The individual MoCA domain scores demonstrated high factor loadings with standard neuropsychological measures purported to measure similar cognitive constructs. DISCUSSION: These findings provide empirical validation for the MoCA domain classifications, lending further support for the use of the MoCA as a cognitive screen that reflects similar constructs as those measured by a comprehensive battery.

Using negative feedback to guide behavior: impairments on the first 4 cards of the Wisconsin Card Sorting Test predict negative symptoms of schizophrenia.

Research has demonstrated that individuals with schizophrenia fail to appropriately use negative feedback to guide learning. These learning deficits are thought to arise from abnormalities in midbrain dopamine activity. Primary and enduring negative symptoms are also associated with abnormal dopamine activity and are expected to produce more severe deficits in learning when they present in individuals with schizophrenia. The current study examines this matter by comparing individuals with deficit syndrome schizophrenia, which is characterized by primary and enduring negative symptoms, to individuals with nondeficit syndrome schizophrenia and to normal controls in their use of positive feedback and negative feedback to guide learning on the first four cards of the WCST. Participants included 67 individuals with schizophrenia (15 deficit; 52 nondeficit syndrome) and 51 healthy controls. Accuracy data from the first 4 cards of the WCST and measures of global test performance were examined. Individuals with schizophrenia were significantly less accurate than controls in their performance on early (pre-shift) WCST trials, and this impairment was significantly greater in patients with deficit than nondeficit schizophrenia. Additionally, accuracy across the first 4 WCST cards significantly predicted the number of categories completed and percentage of perseverative errors across the entire test. These findings suggest that negative symptoms of schizophrenia are associated with difficulty using negative feedback to adaptively guide behavior, and are consistent with the notion that abnormal DA signaling contributes to the higher-order executive functioning impairments seen in schizophrenia with severe negative symptoms.

Ten-year review of intussusception at Starship Hospital: 1998-2007.

AIMS: To review the demographics, presenting features, rates of air enema reduction success, prevalence of pathological lead points and surgical intervention rates and outcomes in patients with intussusception at Starship Children's Hospital (Auckland, New Zealand). To use this data to guide management of children at a national level in New Zealand. METHOD: Retrospective case series. Patients discharged from Starship Children's Hospital between 1 January 1998 and 31 December 2007 with a diagnosis of intussusception were obtained from coding data. RESULTS: 189 patients were analysed. 30% presented with the classic triad of pain, rectal bleeding and mass. 150/189 proceeded to air enema reduction which was successful in 118 (78.7%) of cases with 2 perforations. 54/189 (28.6%) proceeded for operative reduction of which 26 patients required surgical resection. Clinical and radiological evidence of bowel obstruction and duration of symptoms were associated with failed enema and surgical resection. CONCLUSION: Intussusception only occasionally presents with the typical triad of abdominal pain, rectal bleeding and abdominal mass. Air enema reduction is successful at this institution with a low level of complication. Maori and Pacific patients had higher rates of failed enema reduction and need for surgery compared to European patients. Further research is needed from peripheral centres to evaluate outcomes of children treated in district hospitals to identify how and where these children are best managed.

Upper airway size while sucking on a pacifier in an infant with micrognathia.

In an infant with micrognathia, who was being evaluated after an apparent life-threatening event, respiration timed lateral radiographs showed an increase in the width of the middle airway space during inspiration from 2 mm without the pacifier to 9 mm while sucking on a pacifier. This observation is consistent with the hypothesis that the well-documented association between the pacifier use and reduced risk of sudden infant death syndrome may be at least in part related to changes in airway size.

Do radiographs requested from a paediatric emergency department in New Zealand need reporting?

OBJECTIVES: To ascertain whether plain radiographs interpreted by doctors working in a paediatric ED need reporting by radiologists. METHODS: Prospective observational study based in a paediatric teaching hospital. RESULTS: The overall disagreement rate was 26.1%. The clinically significant disagreement rate was 4.8%. There was no relationship between seniority or confidence of ED doctor, and likelihood of disagreement. Disagreement was more likely where radiographs were interpreted during normal working hours (P < 0.05). Chest films, then abdominal films, then skeletal films were more likely to result in disagreement (P < 0.0001). However, this relationship was reversed when considering rates of clinically significant disagreement (P < 0.05). The highest risk of disagreement was in chest films initially thought to be normal, and the lowest in skeletal films initially thought to be abnormal. CONCLUSION: All radiographs requested on patients discharged from the paediatric ED should be reported. Reporting need not be immediate.

Effect of sub-elite competitive running on bone density, body composition and sexual maturity of adolescent females.

The attainment of optimal peak bone mass during adolescence is important in the primary prevention of osteoporosis. Exercise may contribute to skeletal development and bone density during growth, although competitive exercise is suggested to have an adverse effect. This study assesses the effect of moderate exercise on the bone density of adolescent females. Additionally, other factors which significantly influence attainment of peak bone mass were identified. This was a cross-sectional study of 42 adolescent females, classified as runners (n=15) or non-runners (n=27). Nutrient intake, energy expenditure, menstrual history and pubertal stage were recorded. Bone age, skinfold thickness, body composition and bone mineral density (BMD) of total body, lumbar spine and proximal femur were measured. Statistical analyses used Student's t-test, Pearson correlation and multiple regression analyses. Runners had lower fat mass and higher lean mass, with a trend to higher BMD in all sites measured. There were no significant differences in menstrual cycle regularity, age at menarche or number who had attained menarche. Pubic hair development was similar in both groups. Breast development was delayed in runners, although this may have been a function of lower fat mass in this group. When subjects were categorized according to menarchal status, postmenarchal girls were significantly taller and heavier, with higher fat mass and significantly higher total body and lumbar spine BMD. There was no significant relationship between BMD at any site and dietary nutrient intake. Multiple regression analyses, using BMD as the dependent variable, identified running status, pubertal stage, fat mass and lean mass as significant determinants. When BMD/height was used, significant determinants in total body BMD were fat mass, pubertal stage and running status, while in the lumbar spine, only the latter two variables remained significant. In conclusion, body composition, physical activity and sexual maturity were identified as significant determinants of bone density during adolescence. Runners had significantly lower body fat than non-runners, but this did not interfere with hormonal cyclicity, and caused no detriment to their bone density. The results of this study are reassuring, since they indicate that sub-elite competitive athletics has no detrimental effect on bone mass accrual in adolescent females.