Predicted Group Status Research Articles

Validation of the multi-day Boston remote assessment of neurocognitive health (BRANCH) among cognitively impaired & unimpaired older adults.

The multi-day Boston Remote Assessment of Neurocognitive Health (BRANCH) is a remote, web-based assessment designed to capture the earliest cognitive changes in the preclinical stage of Alzheimer's disease (AD). It has been validated in unimpaired older adults, but as individuals progress on the AD continuum, assessments need to remain feasible and valid at different clinical stages. The focus of this study was to assess feasibility and validity of multi-day BRANCH in participants with and without cognitive impairment. For seven days participants completed the BRANCH paradigm to capture a muti-day learning curve score. Participants also completed the mini-mental-status-exam (MMSE) and the Quick Dementia Rating Scale (QDRS). The primary cohort included 81 older adults: 38 with cognitive impairment (CI) and 43 cognitively-unimpaired (CU). A complementary replication cohort included 16 participants with consensus-defined mild cognitive impairment (MCI) and 47 demographically-matched cognitively unimpaired participants. Multi-day BRANCH was feasibile with 92 % or participants completing all seven days of testing. More CI than CU reported nervousness and found tasks slightly less enjoyable on Day 1, but ratings increased at a similar rate in both groups. Convergent validity was confirmed by a positive association between BRANCH and total MMSE and QDRS scores. There was a large effect size of group status on BRANCH (CI vs. CU; Cohen's d = 0.83) and per logistic regression, BRANCH significantly predicted group status (β = -1.49, p < 0.001); even more so between MCI and CU in the replication cohort. Findings suggest that a remotely administered web-based assessment of multi-day learning is feasible and valid in participants with and without cognitive impairment.

Impaired perceptual discrimination of complex objects in older adults at risk for dementia.

Tau pathology accumulates in the perirhinal cortex (PRC) of the medial temporal lobe (MTL) during the earliest stages of the Alzheimer's disease (AD), appearing decades before clinical diagnosis. Here, we leveraged perceptual discrimination tasks that target PRC function to detect subtle cognitive impairment even in nominally healthy older adults. Older adults who did not have a clinical diagnosis or subjective memory complaints were categorized into "at-risk" (score <26; n = 15) and "healthy" (score ≥26; n = 23) groups based on their performance on the Montreal Cognitive Assessment. The task included two conditions known to recruit the PRC: faces and complex objects (greebles). A scene condition, known to recruit the hippocampus, and a size control condition that does not rely on the MTL were also included. Individuals in the at-risk group were less accurate than those in the healthy group for discriminating greebles. Performance on either the face or size control condition did not predict group status above and beyond that of the greeble condition. Visual discrimination tasks that are sensitive to PRC function may detect early cognitive decline associated with AD.

The complementary utility of cognitive testing and the medication management ability assessment in older adults.

Older adults are susceptible to cognitive declines that may limit independence. Though neuropsychologists opine about risk of functional decline, the degree to which cognitive testing and in-office simulations approximate everyday behavior is unclear. We assessed the complementary utility of cognitive testing and the face-valid Medication Management Ability Assessment (MMAA) to predict medication management among older adults. This was a retrospective study of 234 older adults (age = 72 ± 7.7 years; 59% women) who completed the MMAA during outpatient neuropsychological evaluations. Based on comprehensive clinical assessment, most participants (n = 186) were independent in medication management, while 48 received assistance. Demographically adjusted composite scores were derived for attention/processing speed (A/PS), executive functioning (EF), visuospatial/constructional ability (VC), language, and memory domains. Univariate differences in cognition were examined across Assisted versus Independent groups. Logistic regression assessed which cognitive domains independently predicted group status. The incremental value of the MMAA was assessed, holding uniquely associated cognitive test scores constant. Those receiving assistance with medication management performed worse across all neurocognitive domains and the MMAA compared with independent counterparts. EF was the only unique cognitive predictor of medication management status. When modeled alone, EF and MMAA performance correctly classified 79.5% and 80.8% of cases, respectively. When modeled together, both were independently associated with medication management status and correctly classified 83.3% of cases. EF uniquely predicted medication management status beyond other cognitive domains. The MMAA provided complementary predictive utility. Concurrent interpretation of executive functioning and MMAA performance is advised when assessing older adults suspected of medication mismanagement. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

VR Toolkit for Identifying Group Characteristics

Visualising crowds is a key pedestrian dynamics topic, with significant research efforts aiming to improve the current state-of-the-art. Sophisticated visualisation methods are a standard for modern commercial models, and can improve crowd management techniques and sociological theory development. These models often define standard metrics, including density and speed. However, modern visualisation techniques typically use desktop screens. This can limit the capability of a user to investigate and identify key features, especially in real time scenarios such as control centres. Virtual reality (VR) provides the opportunity to represent scenarios in a fully immersive environment, granting the user the ability to quickly assess situations. Furthermore, these visualisations are often limited to the simulation model that has generated the dataset, rather than being source-agnostic. In this paper we implement an immersive, interactive toolkit for crowd behaviour analysis. This toolkit was built specifically for use within VR environments and was developed in conjunction with commercial users and researchers. It allows the user to identify locations of interest, as well as individual agents, showing characteristics such as group density, individual (Voronoi) density and speed. Furthermore, it was used as a data-extraction tool, building individual fundamental diagrams for all scenario agents, and predicting group status as a function of local agent geometry. Finally, this paper presents an evaluation of the toolkit made by crowd behaviour experts.

State-dependent signatures of anti-N-methyl-d-aspartate receptor encephalitis.

Traditional static functional connectivity analyses have shown distinct functional network alterations in patients with anti-N-methyl-d-aspartate receptor encephalitis. Here, we use a dynamic functional connectivity approach that increases the temporal resolution of connectivity analyses from minutes to seconds. We hereby explore the spatiotemporal variability of large-scale brain network activity in anti-N-methyl-d-aspartate receptor encephalitis and assess the discriminatory power of functional brain states in a supervised classification approach. We included resting-state functional magnetic resonance imaging data from 57 patients and 61 controls to extract four discrete connectivity states and assess state-wise group differences in functional connectivity, dwell time, transition frequency, fraction time and occurrence rate. Additionally, for each state, logistic regression models with embedded feature selection were trained to predict group status in a leave-one-out cross-validation scheme. Compared to controls, patients exhibited diverging dynamic functional connectivity patterns in three out of four states mainly encompassing the default-mode network and frontal areas. This was accompanied by a characteristic shift in the dwell time pattern and higher volatility of state transitions in patients. Moreover, dynamic functional connectivity measures were associated with disease severity and positive and negative schizophrenia-like symptoms. Predictive power was highest in dynamic functional connectivity models and outperformed static analyses, reaching up to 78.6% classification accuracy. By applying time-resolved analyses, we disentangle state-specific functional connectivity impairments and characteristic changes in temporal dynamics not detected in static analyses, offering new perspectives on the functional reorganization underlying anti-N-methyl-d-aspartate receptor encephalitis. Finally, the correlation of dynamic functional connectivity measures with disease symptoms and severity demonstrates a clinical relevance of spatiotemporal connectivity dynamics in anti-N-methyl-d-aspartate receptor encephalitis.

A-182 Development of a PTSD-Specific Embedded Validity Measure in the Personality Assessment Inventory

Abstract Objective/Background The present study investigated the feasibility of developing a PTSD-specific malingering scale embedded within the Personality Assessment Inventory (PAI). Methods Participants consisted of 489 individuals [mean age = 20.0 (SD = 3.29); 71% female; 73.0% Caucasian, 17.6% African American, 3.5%, 9.4% Other] who completed PAI. 274 individuals were in the control group and instructed to answer normally while 215 were instructed to simulate PTSD with intent to successfully feign PTSD in the context of a legal case. The following were identified as candidate PAI subscales for logistic regression to identify feigned PTSD: ARD-T, BOR-A, SCZ-T, ANX-P, and DEP-P. Results Logistic regression analysis was performed with known group as the dependent variable and PAI subtest normed T-scores as predictor variables. The final full model of five predictor variables significantly predicted group status (χ2 = 384.9, df = 5, N = 489, p &amp;lt; 0.001). The model accounted for 54.5% to 73.0% of the variance (Cox and Snell R2 = 0.545; Nagelkerke R2 = 0.730) in performance classification with overall 89.4% of individuals correctly predicted to their known group. At a cut value of 0.65 the specificity was 94.9%, and the sensitivity was 82.3%. Within the model, the following variables were incrementally predictive of group membership: ARD-T (B = 0.05, p &amp;lt; 0.001), BOR-A (B = 0.04, p &amp;lt; 0.05), and ANX-P (B = 0.04, p &amp;lt; 0.05). Conclusions Preliminary evidence for use of an embedded PAI malingering scale within the PAI was found. Further replication is needed in clinical populations prior to use in practice.

A-206 “Mittenberg-Type formula for Identifying Feigned ADHD Using WAIS-IV”

Abstract Objective This study utilized logistic regression to determine whether performance patterns on the WAIS-IV subtests could differentiate between genuine-effort and simulated ADHD groups. Method Participants were 355 college students (55.3%% female; 65.7% Caucasian, 23.9% African American, 4.2% Asian; age range 17–51 years, Mage = 20.93 years, SD = 4.63; 76.4% no psychological diagnosis) who completed the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV). Mean FSIQ for control group was 102.35 and 87.48 for the simulator group. Eighty participants (22.5%) simulated ADHD symptoms, while 276 participants (77.5%) provided genuine effort. Results A logistic regression analysis was performed with known group as the dependent variable and WAIS-IV subtest scaled scores as predictor variables. The final model of five predictor variables (Similarities, Information, Digit Span, Symbol Search, and Coding) significantly predicted group status (χ2 = 140.91, df = 5, N = 355, p &amp;lt; .001). The model accounted for 33% to 50% of the variance (Cox and Snell R2 = .33; Nagelkerke R2 = .50) in performance classification with overall 86% of individuals correctly predicted to their known group. At a cut value of .65 the sensitivity was 69.6% and the specificity was 90.6%. A cut value of.55 the sensitivity was 53.2% and the specificity was at 94.6%. Conclusions These findings are consistent with prior research suggesting discriminant function analysis derived from clinical measures (e.g., WAIS-IV) can be useful as embedded validity measures in distinguishing suspicious and genuine performance. Sensitivity, specificity, and predictive power of the WAIS-IV subtests were acceptable at 5% and 10% false positive rates.

Detecting feigned traumatic brain injury with eye tracking during a test of performance validity.

Eye-tracking is a promising technology to enhance assessment of performance validity. Research has established that ocular behaviors are reliable biomarkers of (un)conscious cognitive processes, and they have distinguished deceptive from honest responding in experimental paradigms. This study examined the incremental utility of eye-tracking on a clinical performance validity test (PVT) in distinguishing adults with verified TBI from adults coached to feign cognitive impairment. Participants were 49 adults with moderate-to-severe TBI (TBI), 47 healthy adults coached to simulate TBI (SIM), and 67 healthy comparisons providing full effort (HC). A PVT linked to eye-tracking was completed in the context of a full neuropsychological battery. Kruskal-Wallis tests revealed that eye-tracking indices did not differ among the groups during presentation of stimulus items but did differ during forced-choice trials. Compared to TBI and HC, SIM had significantly more transitions, fixations, and time spent looking at correct and incorrect response options. Logistic regressions and ROC curve analyses showed that accuracy was the best predictor of SIM versus HC. For SIM versus TBI, eye-tracking indices exceeded accuracy in distinguishing the groups. Eye-tracking added incremental predictive value to accuracy for both SIM-HC and SIM-TBI discriminations. Eye-tracking indicated that persons feigning TBI showed multiple signs of greater cognitive effort than persons with verified TBI and healthy comparisons. In the comparison of greatest interest (SIM vs. TBI) eye-tracking best predicted group status and yielded excellent discrimination when combined with accuracy. Eye-tracking may be an important complement to traditional accuracy scores on PVTs. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Digit Span embedded validity indicators in neurologically-intact veterans

Objective: Embedded validity measures are useful in neuropsychological evaluations but should be updated with new test versions and validated across various samples. This study evaluated Wechsler Adult Intelligence Scale, 4th edition (WAIS-IV) Digit Span validity indicators in post-deployment veterans.Method: Neurologically-intact veterans completed structured diagnostic interviews, the WAIS-IV, the Medical Symptom Validity Test (MSVT), and the b Test as part of a larger study. The Noncredible group included individuals who failed either the MSVT or the b Test. Of the total sample (N = 275), 21.09% failed the MSVT and/or b Test. Diagnostic accuracy was calculated predicting group status across cutoff scores on two Digit Span variables, four Reliable Digit Span (RDS) variables, and two Vocabulary minus Digit Span variables.Results: Digit Span age-corrected scaled score (ACSS) had the highest AUC (.648) of all measures assessed; however, sensitivity at the best cutoff of <7 was only 0.17. Of RDS measures, the Working Memory RDS resulted in the highest AUC (.629), but Enhanced RDS and Alternate RDS produced the highest sensitivities (0.22). Overall, cutoff scores were consistent with other studies, but sensitivities were lower. Vocabulary minus Digit Span measures were not significant.Conclusions: Digit Span ACSS was the strongest predictor of noncredible performance, and outperformed traditional RDS variants. Sensitivity across all validity indicators was low in this research sample, though cutoff scores were congruent with previous research. Although embedded Digit Span validity indicators may be useful, they are not sufficient to replace standalone performance validity tests.

Suicidal thoughts and behaviors are associated with an increased decision-making bias for active responses to escape aversive states.

Suicide is a leading cause of death worldwide. Despite decades of clinical and theoretical accounts that suggest that suicidal thoughts and behaviors are efforts to escape painful emotions, little prior research has examined decision making involved in escaping aversive states. We compared the performance of 85 suicidal participants to 44 nonsuicidal psychiatric patients on a novel reinforcement learning task with choices to make either active (i.e., "go") or passive responses (i.e., "no-go") to either escape or avoid an aversive stimulus. We used a computational cognitive model to isolate decision-making biases. We hypothesized that suicidal participants would exhibit a relatively elevated bias for making active responses to escape an aversive state and would show worse performance when escape required a passive response (i.e., "doing nothing" to escape). Our hypotheses were supported: The computational model revealed that suicidal participants exhibited a higher bias for an active response to escape compared with nonsuicidal psychiatric controls, suggesting that this finding was not just the result of the presence of psychopathology. The bias parameter also accounted for unique variance in predicting group status among several constructs previously related to suicidal thoughts and behaviors. This study provides a new method for testing escape decision making and does so using a computational cognitive model, allowing us to precisely index processes underlying suicidal and related behaviors. Future research examining escape decision making from a computational perspective could help link neural processes or environmental stressors to suicidal thoughts or behaviors. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Workers Who Stay at Work Despite Chronic Nonspecific Musculoskeletal Pain: Do They Differ from Workers with Sick Leave?

Purpose Most workers with chronic nonspecific musculoskeletal pain (CMP) do not take sick leave, nor consult a health care professional or search vocational rehabilitation. Yet, the knowledge of many researchers, clinicians and policy makers is largely based on people with CMP who discontinue work. The aim of this study was to explore characteristics of workers who stay at work despite CMP, and to compare these with sick-listed workers with CMP following vocational rehabilitation. Methods The clinical characteristics of workers who stay at work despite CMP (n = 119) and sick-listed workers who follow vocational rehabilitation (n = 122) were described and the differences between these groups were assessed. Logistic regression analysis was used to assess differences between the groups and to determine which variables predicted group status. Results Workers who stayed at work despite CMP reported significantly lower levels of fear avoidance (OR = 0.94), pain catastrophizing (OR = 0.93), perceived workload (OR = 0.93), and higher pain acceptance (OR = 1.11), life control (OR = 1.62) and pain self-efficacy (OR = 1.09) compared to sick-listed workers following rehabilitation, even after controlling for confounders. The groups did not differ on physical activity level, active coping and work satisfaction. Group status was predicted best by pain intensity, duration of pain, pain acceptance, perceived workload, mental health, and psychological distress (area under the receiver operating characteristic curve = 0.91, 95% CI = 0.87–0.95). Conclusions A wide range of characteristics of workers who stay at work despite CMP were explored. Relevant differences from sick-listed workers with CMP were observed in all domains of the bio-psycho-social model. Six main predictors were identified that best discriminate between both groups.

Predictors of Sexual Desire Disorders in Women

A historic belief was that testosterone was the "hormone of desire." However, recent data, which show either minimal or no significant correlation between testosterone levels and women's sexual desire, suggest that nonhormonal variables may play a key role. To compare women with hypoactive sexual desire disorder (HSDD) and those with the recently proposed more symptomatic desire disorder, Sexual Desire/Interest Disorder (SDID), on the relative contribution of hormonal vs. nonhormonal variables. Women with HSDD (N = 58, mean age 52.5) or SDID (N = 52, mean age 50.9) participated in a biopsychosocial assessment in which six nonhormonal domains were evaluated for the degree of involvement in the current low desire complaints. Participants provided a serum sample of hormones analyzed by gas chromatography-mass spectrometry or liquid chromatography/mass spectrometry/mass spectrometry. Logistic regression was used to assess the ability of variables (nonhormonal: history of sexual abuse, developmental history, psychosexual history, psychiatric status, medical history, and sexual/relationship-related factors; hormonal: dehydroepiandrosterone [DHEA], 5-diol, 4-dione, testosterone, 5-α-dihydrotestosterone, androsterone glucuronide, 3α-diol-3G, 3α-diol-17G, and DHEA-S; and demographic: age, relationship length) to predict group membership. Women with SDID had significantly lower sexual desire and arousal scores, but the groups did not differ on relationship satisfaction or mood. Addition of the hormonal variables to the two demographic variables (age, relationship length) did not significantly increase predictive capability. However, the addition of the six nonhormonal variables to these two sets of predictors significantly increased ability to predict group status. Developmental history, psychiatric history, and psychosexual history added significantly to the predictive capability provided by the basic model when examined individually. Nonhormonal variables added significant predictive capability to the basic model, highlighting the importance of their assessment clinically where women commonly have SDID in addition to HSDD, and emphasizing the importance of addressing psychological factors in treatment.

Differences in Rapid Initiation and Termination of Voluntary Postural Sway Associated with Ageing and Falls-Risk

ABSTRACT The authors examined differences between young adults (n = 25) and healthy older adults (n = 48) in reaction time and the relations between center of pressure (COP) and center of mass (COM) motions during rapid initiation and termination of voluntary postural sway. Older adults were divided into low and high falls-risk groups based on Physiological Profile Assessment scores of sensorimotor function. Low falls-risk older adults had slower reaction times during anteroposterior sway initiation and decreased COP–COM separation during anteroposterior and medialateral sway initiation and anteroposterior continuous voluntary sway compared with young adults. High falls-risk older adults had slower initiation and termination reaction times in all response directions and decreased COP–COM separation during sway initiation and continuous voluntary sway in the anteroposterior and medialateral directions compared with young adults. Compared with low falls-risk older adults, high falls-risk older adults had slower initiation and termination reaction times in all response directions and decreased COP–COM separation during medialateral continuous voluntary sway. Reaction time and COP–COM measures significantly predicted group status in discriminant models with sensitivities and specificities of 72–100%. Overall, these findings highlight important associations of age-related declines in sensorimotor function related to an increased risk of falling with slower postural reaction time and reduced postural stability.

Depressive symptoms and suicidality in women experiencing intimate partner violence

Study objectives: We compare 2 groups of abused black female emergency department (ED) patients (suicide attempters and nonattempters) with regard to specific depressive symptoms. Methods: The study was a cross-sectional examination of intimate partner violence (IPV)–positive black women who presented to the medical or psychiatric ED for treatment. Black women with a recent history of IPV who presented after an attempted suicide (n=100) were compared with demographically comparable IPV-positive black women who had not attempted suicide and presented for treatment of another condition (n=100). Women completed face-to-face interviews on several measures, including demographics and the Beck Depression Inventory-II (BDI-II). Multivariate analysis of variance was used to test the hypothesis that attempters would report higher levels on the BDI-II items compared with their nonattempting counterparts. Analyses of variance were used to assess on which specific BDI-II items the groups differed. A logistic regression analysis, using the BDI-II variables with moderate effect sizes, was conducted to predict group status. Results: Overall, there were no demographic differences between cases and controls. Attempters reported statistically significant higher scores on all 21 BDI-II items than did nonattempters. Four BDI-II items had effect size values in the medium range: sadness, self-dislike, suicidal thoughts, and feelings of worthlessness. The logistic regression model using these 4 variables correctly predicted group status 78% of the time. Conclusion: IPV patients who attempt suicide have higher levels of depressive symptoms than nonattempters. Symptoms of sadness, self-dislike, suicidal thoughts, and feelings of worthlessness had the highest predictive value. These 4 items can be used as a brief screen in the ED to detect female IPV patients at increased risk for suicidal behavior. Study objectives: We compare 2 groups of abused black female emergency department (ED) patients (suicide attempters and nonattempters) with regard to specific depressive symptoms. Methods: The study was a cross-sectional examination of intimate partner violence (IPV)–positive black women who presented to the medical or psychiatric ED for treatment. Black women with a recent history of IPV who presented after an attempted suicide (n=100) were compared with demographically comparable IPV-positive black women who had not attempted suicide and presented for treatment of another condition (n=100). Women completed face-to-face interviews on several measures, including demographics and the Beck Depression Inventory-II (BDI-II). Multivariate analysis of variance was used to test the hypothesis that attempters would report higher levels on the BDI-II items compared with their nonattempting counterparts. Analyses of variance were used to assess on which specific BDI-II items the groups differed. A logistic regression analysis, using the BDI-II variables with moderate effect sizes, was conducted to predict group status. Results: Overall, there were no demographic differences between cases and controls. Attempters reported statistically significant higher scores on all 21 BDI-II items than did nonattempters. Four BDI-II items had effect size values in the medium range: sadness, self-dislike, suicidal thoughts, and feelings of worthlessness. The logistic regression model using these 4 variables correctly predicted group status 78% of the time. Conclusion: IPV patients who attempt suicide have higher levels of depressive symptoms than nonattempters. Symptoms of sadness, self-dislike, suicidal thoughts, and feelings of worthlessness had the highest predictive value. These 4 items can be used as a brief screen in the ED to detect female IPV patients at increased risk for suicidal behavior.

Minor physical anomalies in patients with schizophrenia and their parents: prevalence and pattern of craniofacial abnormalities

The frequency of minor physical anomalies (MPAs) in patients with schizophrenia suggests an early disturbance in the development of the neuroectoderm. To improve the phenotypic delimitation of this disorder, we used a comprehensive scale of MPAs (41 items) in patients with schizophrenia and their first-degree relatives. This scale, adapted from a revised version of the Waldrop Scale (Ismail et al. Minor physical anomalies in schizophrenic patients and their siblings, American Journal of Psychiatry 155, 1998a, 1695–1702), introduced new items assessing facial and limbs asymmetry. The interrater reliability between two examiners was good: intraclass correlation coefficient: 0.68 (0.42–0.92). Patients with schizophrenia ( n=40; mean=5.8, S.D.=4) and their non-psychotic parents ( n=45; mean=4.7, S.D.=2.8) had significantly more MPAs than healthy comparison subjects ( n=42; mean=2.2, S.D.=1.2). A logistical regression model showed the ability of several items to predict group status, including facial asymmetry, cleft palate, hair whorls and abnormal palmar crease. The high prevalence of facial asymmetry in patients with schizophrenia and their first-degree relatives provides new insights into the underlying dysembryogenic processes. This revised scale thus appears to be a useful complementary tool in pathophysiological studies aiming at the identification of developmental factors in schizophrenia.

The Effects of Coaching on the Sensitivity and Specificity of Malingering Measures

This study sought to identify patterns of performance indicative of malingering on the Auditory Verbal Learning Test (AVLT). Participants were randomly assigned to perform normally, simulate head injury, or simulate head injury with warning that there might be attempts to detect malingering. Participants completed an expanded AVLT and a forced-choice task, in addition to several other memory tests. The warned simulators performed worse than normals on the forced-choice task, but better than those simulating head injury without a warning, suggesting that the warned subjects recognized forced choice as a malingering test. A combination of AVLT indices was able to predict group status for both nai;ve and warned malingerers (73.6% for nai;ve malingerers, 84.8% for warned, no false positives). The forced-choice measure detected only 31.6% of the nai;ve malingerers when specificity was maximized, and detected only 6.5% of the warned malingerers, a significant drop in detection rate. Findings suggest that pattern of performance indices are useful in detecting malingering, even when subjects are aware of attempts to detect malingering.

The Effects of Coaching on the Sensitivity and Specificity of Malingering Measures

This study sought to identify patterns of performance indicative of malingering on the Auditory Verbal Learning Test (AVLT). Participants were randomly assigned to perform normally, simulate head injury, or simulate head injury with warning that there might be attempts to detect malingering. Participants completed an expanded AVLT and a forced-choice task, in addition to several other memory tests. The warned simulators performed worse than normals on the forced-choice task, but better than those simulating head injury without a warning, suggesting that the warned subjects recognized forced choice as a malingering test. A combination of AVLT indices was able to predict group status for both nai;ve and warned malingerers (73.6% for nai;ve malingerers, 84.8% for warned, no false positives). The forced-choice measure detected only 31.6% of the nai;ve malingerers when specificity was maximized, and detected only 6.5% of the warned malingerers, a significant drop in detection rate. Findings suggest that pattern of performance indices are useful in detecting malingering, even when subjects are aware of attempts to detect malingering.

Continuous Performance Test Results of Adults with Attention Deficit Hyperactivity Disorder

Although Attention Deficit Hyperactivity Disorder (ADHD) is well established as a diagnosis in childhood, the diagnosis in adults remains controversial. The present study compared the Continuous Performance Test (CPT) performance of 60 clinic-referred adults with current ADHD symptomatology to normal subjects. Adults with current ADHD symptoms were found to make more errors of omission and commission than did normal adults. The signal detection theory variable, d', indicated that patients with ADHD were less sensitive to stimulus features than were normals. Using several CPT measures to predict group status, the CPT appeared to be of moderate clinical utility. These CPT results lend convergent validity to similar results in child populations and help to establish ADHD as a valid disorder of adulthood.

Survivorship Bias

<h3>Abstract</h3> Diagnosis and symptom severity in schizophrenia is associated with irregularities across neural oscillatory frequency bands, including theta, alpha, beta, and gamma. However, electroencephalographic signals consist of both periodic and aperiodic background activity, characterized by the (1/f) slope of the power spectrum. We compared traditional band-limited periodic oscillatory activity to aperiodic activity, in schizophrenia participants and healthy controls, during an attention task. Classification analysis revealed that the change in slope of the power spectrum better predicted group status than traditional oscillatory power. It even outperformed the predictions made using participants’ own behavioral performance. Additionally, the differences in slope were highly consistent as they were observed across all electrodes. In sum, the aperiodic slope appears to be a more accurate, consistent, and robust metric to differentiate schizophrenic patients from healthy controls. <h3>Significance statement</h3> Understanding the neurobiological origins of schizophrenia and identifying reliable and consistent biomarkers are of critical importance in improving treatment of that disease. Numerous studies have reported disruptions to neural oscillations in schizophrenia patients. This has, in part, led to schizophrenia being characterized as a disease of disrupted neural coordination, reflected by changes in frequency band power. We report however that changes in aperiodic background noise (i.e., spectral slope) can also predict clinical status. Unlike band-limited power though, the aperiodic slope predicts status better than participants’ own behavioral performance. Furthermore, it is a consistent predictor across all electrodes. Alterations in aperiodic noise are consistent with well-established inhibitory neuron dysfunctions associated with schizophrenia, allowing for a direct link between noninvasive EEG and chronic, widespread, neurobiological deficits.

Cardiac performance in children with homozygous sickle cell disease

Cardiac function was evaluated in 24 children from a Jamaican sickle cell cohort study. Ten patients with sickle cell disease underwent echocardiographic studies on their eighth birthday. The results were compared with 14 age- and sex-matched control children born within hours of the index patients. Left ventricular dimension index (systolic 2.89 +/- 0.31 versus 2.33 +/- 0.42 cm and diastolic 4.70 +/- 0.35 versus 3.64 +/- 0.48 cm, p = 0.001), diastolic volume (79.4 +/- 17.1 versus 60.8 +/- 7.8 ml, p = 0.01), left ventricular mass index (116.3 +/- 3.4 versus 74.3 +/- 15.2 g/m2, p = 0.001) and cardiac index (5.51 +/- 1.32 versus 3.38 +/- 0.85 liters/min per m2 p = 0.001) were significantly increased in patients with sickle cell disease compared with values in control subjects. However, there was no statistically significant difference between the two groups for ejection fraction, velocity of circumferential fiber shortening, percent fractional shortening, systolic time intervals, wall stress and ratio of wall stress-systolic volume. Although two mean ratios of wall stress-systolic volume index were lower in children with sickle cell disease as compared with control subjects (4.0 +/- 0.7 versus 5.4 +/- 1.7, p = 0.02 and 5.9 +/- 1.2 versus 8.3 +/- 2.5, p = 0.005, respectively), the range of ratios remained within normal limits (3.4 to 5.8 in children with sickle cell disease versus 2.8 to 9.5 in controls and 4.2 to 8.3 versus 3.8 to 12.5, respectively). Furthermore, only body surface area predicted group status independent of other variables (p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)