Psychogenic or neurogenic origin of agrammatism and foreign accent syndrome in a bipolar patient: a case report

BACKGROUND: Foreign accent syndrome (FAS) is a rare speech disorder characterized by the appearance of a new accent, different from the speaker's native language and perceived as foreign by the speaker and the listener. In most of the reported cases, FAS follows stroke but has also been found following traumatic brain injury, cerebral haemorrhage and multiple sclerosis. In very few cases, FAS was reported in patients presenting with psychiatric disorders but the link between this condition and FAS was confirmed in only one case. CASE PRESENTATION: In this report, we present the case of FG, a bipolar patient presenting with language disorders characterized by a foreign accent and agrammatism, initially categorized as being of psychogenic origin. The patient had an extensive neuropsychological and language evaluation as well as brain imaging exams. In addition to FAS and agrammatism, FG also showed a working memory deficit and executive dysfunction. Moreover, these clinical signs were related to altered cerebral activity on an FDG-PET scan that showed diffuse hypometabolism in the frontal, parietal and temporal lobes bilaterally as well as a focal deficit in the area of the anterior left temporal lobe. When compared to the MRI, these deficits were related to asymmetric atrophy, which was retrospectively seen in the left temporal and frontal opercular/insular region without a focal lesion. DISCUSSION: To our knowledge, FG is the first case of FAS imaged with an (18)F-FDG-PET scan. The nature and type of neuropsychological and linguistic deficits, supported by neuroimaging data, exclude a neurotoxic or neurodegenerative origin for this patient's clinical manifestations. For similar reasons, a psychogenic etiology is also highly improbable. CONCLUSION: To account for the FAS and agrammatism in FG, various explanations have been ruled out. Because of the focal deficit seen on the brain imaging, involving the left insular and anterior temporal cortex, two brain regions frequently involved in aphasic syndrome but also in FAS, a cerebrovascular origin must be considered the best explanation to account for FG's language deficits

PSYCHOMETRIC EVALUATION OF AN EXECUTIVE FUNCTION BATTERY FOR PEDIATRIC SICKLE CELL DISEASE

Sickle Cell Disease (SCD) is a genetic disorder which affects hemoglobin and is associated with high rates of neurologic and neurocognitive deficits. Recent studies have indicated executive functioning (EF) as a common area of impairment for children diagnosed with SCD; however, there is no consensus about which measures of executive function are best to use in clinical practice or research. The purpose of the present research is to assess the properties of a new executive function measure, the “EXAMINER” to determine its utility with the SCD population. Thirty-two children with SCD and 86 demographically-matched controls completed established cognitive measures known to be sensitive to SCD-related neurocognitive deficits as well as EXAMINER tasks of executive attention, set shifting, working memory, inhibition, planning, and fluency. A statistical analysis compared performance on the attention, set shifting, inhibition, planning, and fluency measures in the EXAMINER relative to established measures (i.e., the verbal comprehension, processing speed, short term memory measures in the Woodcock Johnson Tests of Cognitive Abilities III) to compare reliability and validity. It was expected that the EXAMINER would show comparable reliability and validity to the established measures using traditional definitions of these constructs. In addition, examination of cultural validity was examined due to the high preponderance of SCD among the African-American population. Statistical analysis indicated support for internal consistency, convergent validity, cultural validity, and sensitivity of the EXAMINER, relative to traditional cognitive measures. Taken together, these results suggest that the EXAMINER is a useful neuropsychological test for the pediatric SCD population. Future research should focus on using more sophisticated scale development approaches, including greater ethnic and economic diversity with norming groups, and incorporating children in the statistical models to further establish strong psychometric properties

The Prevalence Rate and Neurocognitive Morbidity Associated with Obstructive Sleep Apnea in Children with Sickle Cell Disease

Sickle-cell disease (SCD) refers to a group of genetic blood disorders resulting from the inheritance of genes for S-type hemoglobin. The disease is life-long and is associated with multiple complications including pain episodes, organ damage, and neurological morbidities such as stroke, and silent cerebral infarcts which often lead to cognitive dysfunction. Obstructive sleep apnea (OSA) is a serious medical condition characterized by intermittent hypoxemia (reduction in blood oxygen levels), hypoxia, and fragmented sleep that can lead patients to suffer from daytime behavioral and cognitive dysfunction and reduced quality of life. Children with SCD are at high risk for developing OSA, which can increase the likelihood for developing cognitive deficits. The prevalence of OSA in SCD is currently not well-documented; moreover, the relationship between the two conditions and its combined effect of neurocognitive functioning has received little attention to date. The purpose of this study is to describe the prevalence rate of OSA in children with SCD in a large clinic-wide sample and examine the relationship between OSA and neurocognitive morbidity in children with SCD

MRS and Neuropsychological Outcome in Children with Non-accidental TBI

Despite the severe and long-term neurological consequences and the prevalence of non-accidental head trauma (NAT) among infants, few empirical studies have specifically examined the neuropsychological consequences in this population of children. The current study examined the relationship between clinical variables, Magnetic Resonance Spectroscopy (1H-MRS), and neuropsychological outcome in this high-risk population of children. Infants and children with a confirmed diagnosis of NAT were recruited by the Division of Pediatric Neurology at Loma Linda University Children’s Hospital and administered a comprehensive follow-up neuropsychological evaluation and neurological exam several months post injury. At the conclusion of the study, there were 13 participants with a mean age of M = 3.62, SD = 1.61. Results revealed several significant correlations between 1H-MRS, clinical variables, and neuropsychological outcome that are consistent with previous findings as well. As such, the current findings suggest that neurometabolite ratios observed at time of injury can potentially play a significant role in understanding possible functional outcomes the caregivers of these children can expect. Global neuropsychological deficits were also identified among children with non-accidental head trauma, suggesting the need for clinical interventions in this high-risk population. Several significant associations between child deficits observed in this population and parental stress were identified, which has significant implications for the child’s recovery trajectory as well

A multilayer multimodal detection and prediction model based on explainable artificial intelligence for Alzheimer’s disease

Alzheimer’s disease (AD) is the most common type of dementia. Its diagnosis and progression detection have been intensively studied. Nevertheless, research studies often have little effect on clinical practice mainly due to the following reasons: (1) Most studies depend mainly on a single modality, especially neuroimaging; (2) diagnosis and progression detection are usually studied separately as two independent problems; and (3) current studies concentrate mainly on optimizing the performance of complex machine learning models, while disregarding their explainability. As a result, physicians struggle to interpret these models, and feel it is hard to trust them. In this paper, we carefully develop an accurate and interpretable AD diagnosis and progression detection model. This model provides physicians with accurate decisions along with a set of explanations for every decision. Specifically, the model integrates 11 modalities of 1048 subjects from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) real-world dataset: 294 cognitively normal, 254 stable mild cognitive impairment (MCI), 232 progressive MCI, and 268 AD. It is actually a two-layer model with random forest (RF) as classifier algorithm. In the first layer, the model carries out a multi-class classification for the early diagnosis of AD patients. In the second layer, the model applies binary classification to detect possible MCI-to-AD progression within three years from a baseline diagnosis. The performance of the model is optimized with key markers selected from a large set of biological and clinical measures. Regarding explainability, we provide, for each layer, global and instance-based explanations of the RF classifier by using the SHapley Additive exPlanations (SHAP) feature attribution framework. In addition, we implement 22 explainers based on decision trees and fuzzy rule-based systems to provide complementary justifications for every RF decision in each layer. Furthermore, these explanations are represented in natural language form to help physicians understand the predictions. The designed model achieves a cross-validation accuracy of 93.95% and an F1-score of 93.94% in the first layer, while it achieves a cross-validation accuracy of 87.08% and an F1-Score of 87.09% in the second layer. The resulting system is not only accurate, but also trustworthy, accountable, and medically applicable, thanks to the provided explanations which are broadly consistent with each other and with the AD medical literature. The proposed system can help to enhance the clinical understanding of AD diagnosis and progression processes by providing detailed insights into the effect of different modalities on the disease riskThis work was supported by National Research Foundation of Korea-Grant funded by the Korean Government (Ministry of Science and ICT)-NRF-2020R1A2B5B02002478). In addition, Dr. Jose M. Alonso is Ramon y Cajal Researcher (RYC-2016-19802), and its research is supported by the Spanish Ministry of Science, Innovation and Universities (grants RTI2018-099646-B-I00, TIN2017-84796-C2-1-R, TIN2017-90773-REDT, and RED2018-102641-T) and the Galician Ministry of Education, University and Professional Training (grants ED431F 2018/02, ED431C 2018/29, ED431G/08, and ED431G2019/04), with all grants co-funded by the European Regional Development Fund (ERDF/FEDER program)S

Neural correlates of verbal fluency and associations with demographic, mood, cognitive and tumour factors in brain tumour patients.

Verbal fluency tests are one of the most commonly used measures of executive functioning in neuropsychological testing and play an important role in the assessment, diagnosis and care planning of patients with a variety of conditions, including brain tumour. There is little conclusive evidence about which factors may influence verbal fluency outcomes. No studies to date have investigated the interactions between a comprehensive range of demographic variables, mood scores, tumour factors and key cognitive skills with the focus of verbal fluency outcomes in brain tumour patients. Similarly, clarification is required across studies assessing the localisation effects of verbal fluency skills. To address these gaps in the evidence base this study used a retrospective cohort design of cross-sectional data from patients with brain tumours, to investigate their performance of both phonemic and semantic verbal fluency. More specifically this study used simple linear and multiple regression calculations to analyse the interactions between these variables and other potentially important factors such as localisation, depression and anxiety (using the HADS), age, gender, education, premorbid functioning (using the TOPF), semantic memory (using the GNT), and tumour type. The results showed that an increase in phonemic fluency performance was significantly correlated with being educated, an increase in semantic memory, and an increase in premorbid functioning. Phonemic fluency was also significantly correlated with localisation. In general, a decrease in phonemic fluency was significantly associated with tumours in the left frontal lobe. An increase in semantic fluency was correlated with an increase in semantic memory. No other factors showed significant associations with phonemic or semantic fluency. The outcomes from the hierarchical multiple regressions indicated that localisation, gender, education, tumour type, depression, semantic memory, and premorbid functioning when combined can predict phonemic fluency variance. Combining localisation effects, semantic memory, depression and education together do not result in a model that predicts semantic fluency, as within this model the only significant relationship was between semantic memory and semantic fluency. These findings show that, for brain tumour patients, it is important to take into consideration tumour localisation, education, semantic memory, and premorbid functioning when assessing and care planning for deteriorations in phonemic fluency. Similar patients with deteriorations in semantic fluency need to have their results considered in light of performance in semantic memory tests

Program Evaluation of an Executive Functions Intervention at a Middle School Setting

Executive functions play an important role in children’s cognitive, academic and social functioning. The present study investigated the changes in executive functions in students who were enrolled in an academic support period everyday for forty-five minutes. Participants included twenty-six eighth-grade students eligible for Special Education and Related Services in a suburban middle school in New Jersey. The study used archival data consisting of items from the 44-item Executive Functions (EF) Rating Scale, a questionnaire that was completed by middle school special education teachers. To examine differences within groups, repeated measures analysis of variance (ANOVA) were conducted to examine teacher ratings and changes in grades. Although the study did not find a significant difference on EF Rating Scale obtained before, during and immediately after program implementation, of all the students’ mean grades were all within the passing range for the first and second marking periods

A LIFE SPAN APPROACH TO THE RELATIONSHIP BETWEEN CHOLESTEROL, LATE ONSET ALZHEIMER’S DISEASE, AND COGNITIVE FUNCTIONING AMONG OLDER ADULTS

There is evidence that cholesterol presents an important risk factor for Alzheimer’s disease (AD), but the direction of this relationship is modified by age. High cholesterol during midlife and low cholesterol during late life are both associated with an increased risk for AD. This dissertation research engaged a life span approach to study the relationship between cholesterol, AD and cognitive functioning among older adults. The purpose of this research was to determine if trajectories of cholesterol from midlife through late life differ according to AD status and if these trajectories are associated with cognitive functioning during old age. This research employed a secondary analysis of cognitive, phenotypic and genetic data collected from subjects of the Framingham Heart Study (FHS) Original and Offspring Cohorts. Aim One involved creating three summary scores of the FHS neuropsychological battery. ROC analysis was used to determine which score best differentiated between cognitively normal, impaired and dementia subjects. Aim Two used generalized additive mixed models to examine trajectories of total, HDL and total/HDL cholesterol ratio according to AD status in the Original Cohort. Aim Three used mixed-effects models to examine the relationship between subject-specific trajectories of total cholesterol and cognition during old age. Aim One determined that a summary score that provided equal weight to each assessment in the FHS neuropsychological battery best differentiates between subjects classified as cognitively normal, cognitively impaired and dementia. The findings from Aim Two indicated that there are subtle differences in the longitudinal trajectories of total, HDL and total/HDL ratio according to AD status. The findings from Aim Three provide limited evidence for a relationship between subject-specific trajectories of total cholesterol and cognitive functioning later in life. Older adults in the highest quartile for cognitive functioning had lower total cholesterol at approximately 55 years of age, but there were no differences in the mean trajectories of total cholesterol according to cognitive functioning later in life. The findings from this research suggest that older adults with high cognitive functioning have lower total cholesterol during midlife, but life span cholesterol trajectories do not appear to be associated with AD status or cognitive function