Somatosensory processing in the biological relatives of schizophrenia patients: A signal detection analysis of two-point discrimination.

This study examined 2-point discrimination performance in 1st-degree biological relatives (n?=?39) of individuals with schizophrenia and normal adult control participants (n?=?30) recruited from the community. They completed an objective 2-point discrimination task, adapted for use with a signal detection approach to permit separation of discriminability (i.e., sensitivity, d') from response bias/criterion (or motivation, lnβ). Relatives revealed poorer performance on the d' index compared with controls. The 2 groups did not differ on lnβ, suggesting a genuine difference in sensitivity but not response bias. The sensitivity deficit might reflect decreased spatial acuity and/or impaired intensity cue processing of tactile stimuli. Poor performance on the d' index was most closely associated with 2 schizotypic features, namely "odd beliefs/magical thinking." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neurophysiological Evidence for Disturbances of Conflict Processing in Patients With Schizophrenia.

Deficits in cognition are a hallmark of schizophrenia. In the present study, the authors investigated the effects of schizophrenia on the neural correlates of conflict processing in a single-trial version of the Stroop task by using event-related brain potentials. Relative to matched controls, patients with schizophrenia showed increased Stroop interference in response time, but this effect was eliminated when the effect of response slowing was controlled. In controls, conflict processing was associated with a negative wave peaking between 400 and 500 ms (N450) and conflict sustained potential (SP) peaking between 600 and 800 ms after stimulus onset. In patients with schizophrenia, the amplitude of the N450 was significantly attenuated and the conflict SP was absent. These results provide evidence for the existence of altered neural processes associated with conflict processing that may be associated with dysfunction of the anterior cingulate and prefrontal cortex in patients with schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Event-Related fMRI Study of Context Processing in Dorsolateral Prefrontal Cortex of Patients With Schizophrenia.

Context processing is conceptualized as an executive function involved in voluntary, complex actions such as overcoming automatic responses. The present study tested the hypothesis that context-processing deficits in patients with schizophrenia are associated with a dysfunction of left dorsolateral prefrontal cortex (DLPFC). Using event-related functional magnetic resonance imaging (fMRI), 17 controls and 17 medicated patients performed a version of the AX task in which a learned, automatic response had to be inhibited. In controls, left DLPFC activity increased when preparing to overcome an automatic response, whereas patients with schizophrenia showed no differential activation. In controls, context processing appeared to be associated with the differential representation of cues associated with the need to provide top-down support for overcoming automatic responses. This mechanism appeared to be impaired in patients with schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Convergent-Divergent Approach to Context Processing, General Intellectual Functioning, and the Genetic Liability to Schizophrenia.

Convergent and divergent validity are critically important in developing psychological measures that reveal interpretable deficits in disordered populations. This article reports on 2 studies that evaluated the validity of context processing measures. In Experiment 1, a confirmatory factor analysis of data from 481 healthy adults established the convergent validity of 2 context processing measures and showed that context processing accounted for significant amounts of variance in standard IQ and working memory measures. In Experiment 2, 20 schizophrenia patients, 16 of their healthy siblings, and 28 controls were evaluated using a novel, short context processing measure, the dot pattern expectancy (DPX) task. The DPX was sensitive to specific deficits in schizophrenia patients and their healthy siblings. These findings support the construct validity of context processing measures, suggest context processing is a component of intellectual functioning, and demonstrate that brief context processing measures remain sensitive to psychopathological deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive Impairments and Disordered Speech in Schizophrenia: Thought Disorder, Disorganization, and Communication Failure Perspectives.

This article posits that basic cognitive impairments in schizophrenia are more highly related to speech disorder measured as communication failures than speech disorder measured as thought disorder or disorganization. The author tested 47 schizophrenia patients and 36 control participants for sustained attention, sequencing, and conceptual sequencing ability. Their speech was also rated for communication failures, thought disorder, and conceptual disorganization. Attention and sequencing impairments, examined hierarchically, explained a substantial 38% of the variance in the communication measure of speech disorder but little of the variance in formal thought disorder or conceptual disorganization. The author concludes that (a) impairments in attention and sequencing abilities contribute substantially to schizophrenic communication failures, and (b) it is important to consider lower level cognitive "3rd variables" when examining higher level cognitive associates of speech disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The dot pattern expectancy task: Reliability and replication of deficits in schizophrenia.

The dot pattern expectancy (DPX) task was created to efficiently assess context-processing deficits in patients with schizophrenia. Three studies investigated the characteristics of the DPX relevant for clinical applications. To answer questions regarding the psychometric properties of the task, performance on this task was studied in 2 healthy samples. Acceptable reliability and internal consistency and retest reliability were found for most measures of context processing, but not for a difficulty control condition. These characteristics were also found in a suggested brief version (DPXbrf), which may be more practical for clinical purposes. In a 3rd study, schizophrenia patients showed a specific deficit in context processing, replicating previous findings. Findings of these studies indicated some promise for use of this task in measuring context processing and also identified characteristics of this task that need to be strengthened to increase reliability, feasibility, and single-subject interpretability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mispredicting and misremembering: Patients with renal failure overestimate improvements in quality of life after a kidney transplant.

Objective: People tend to overestimate the impact that future events will have on their quality of life. In the case of a medical treatment like kidney transplant, this should result in biased predictions--overestimates of how much the transplant will benefit quality of life. The authors surveyed kidney transplant patients, both before and after transplant, to test whether they would overestimate the benefits of a successful transplant for their quality of life. Design: The authors interviewed 307 patients on a waiting list for cadaveric renal or renal-pancreatic transplant, and 195 patients one year after a successful transplant. A sub sample of patients were interviewed both before and after transplant. Main Outcome Measures: The survey included measures of quality of life, both in terms of an overall estimate (0-100), and across sub domains, including health, employment, and travel. Results: Cross-sectional results suggested that overall quality of life improved after transplant, but the predictions of pretransplant patients overestimated the magnitude of the improvement (p     

Attention, Heart Rate, and Startle Response During Exposure to Trauma-Relevant Pictures: A Comparison of Recent Trauma Victims and Patients With Posttraumatic Stress Disorder.

Victims of a recent trauma were compared with posttraumatic stress disorder (PTSD) patients and healthy controls to assess whether a specific anxiety response and an attentional bias were evident initially or only in chronic PTSD. Heart rate (HR) and startle response were measured, and a dot-probe task was carried out using trauma-relevant pictures. Severely affected recent trauma victims and chronic PTSD patients showed HR acceleration to trauma-related material, which was the only significant group difference. A bias away from trauma-related material was related to severity of intrusions in recent trauma victims, and the bias toward trauma-related material increased with amplitude of the HR response in PTSD patients. A specific anxiety reaction is present initially in severely affected trauma victims. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Context Processing and Context Maintenance in Healthy Aging and Early Stage Dementia of the Alzheimer's Type.

Declines in the ability to process context information may represent a fundamental mechanism of age-related cognitive changes. Two components of context processing--activation/updating and maintenance--were examined in a sample of healthy younger and older adults, along with individuals suffering from early stage dementia of the Alzheimer's type (DAT). All older adult groups showed context activation/updating impairments, whereas context maintenance was only impaired in the oldest adults (age>75 years) and was further exacerbated in DAT individuals. The results suggest that context processing may be composed of functionally dissociable components and point to the utility of this construct in understanding the timecourse of cognitive decline in healthy and pathological aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sensitivity of the mouse to changes in azimuthal sound location: Angular separation, spectral composition, and sound level.

Auditory spatial acuity was measured in mice using prepulse inhibition (PPI) of the acoustic startle reflex as the indicator response for stimulus detection. The prepulse was a “speaker swap” (SSwap), shifting a noise between two speakers located along the azimuth. Their angular separation, and the spectral composition and sound level of the noise were varied, as was the interstimulus interval (ISI) between SSwap and acoustic startle reflex elicitation. In Experiment 1 a 180° SSwap of wide band noise (WBN) was compared with WBN Onset and Offset. SSwap and WBN Onset had near equal effects, but less than Offset. In Experiment 2 WBN SSwap was measured with speaker separations of 15, 22.5, 45, and 90°. Asymptotic level and the growth rate of PPI increased with increased separation from 15 to 90°, but even the 15° SSwap provided significant PPI for the mean performance of the group. SSwap in Experiment 3 used octave band noise (2–4, 4–8, 8–16, or 16–32 kHz) and separations of 7.5 to 180°. SSwap was most effective for the highest frequencies, with no significant PPI for SSwap below 8–16 kHz, or for separations of 7.5°. In Experiment 4 SSwap had WBN sound levels from 40 to 78 dB SPL, and separations of 22.5, 45, 90, and 180°: PPI increased with level, this effect varying with ISI and angular separation. These experiments extend the prior findings on sound localization in mice, and the dependence of PPI on ISI adds a reaction time-like dimension to this behavioral analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Screening for disinhibited disorder cases in a college population: Performance of the SMAST, DAST, SCID-II-Q, and PDQ-4.

Psychiatric disorders characterized by disinhibition--substance use disorders, antisocial personality disorder (PD), and borderline PD--represent a serious risk to the safety and health of college students. The ability of researchers and clinicians to identify students most at risk for disinhibited disorders associated with campus crime, violence, and self-harm depends on measures with strong evidence of diagnostic efficiency, yet data on the diagnostic efficiency of screening measures in college populations are lacking. The authors addressed this need by examining the diagnostic efficiency of commonly used screening measures for disinhibited disorders in a sample of 2,085 students, 79 of whom also completed diagnostic interviews. Results suggest that the diagnostic efficiency (e.g., sensitivity, specificity) of screening measures for substance use disorders and antisocial PD in college samples can be increased by making simple adjustments in screening cutoff criteria. Similar adjustments did not increase the diagnostic efficiency of the screening measure for borderline PD, and this suggested that certain screeners may best be aimed at ruling out disorders. This type of information offers users flexibility with which to tailor the screening threshold to serve different objectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Judging mental disorder in youths: Effects of client, clinician, and contextual differences.

Using a vignette-based, mailed survey of 1,401 experienced psychologists, psychiatrists, and social workers, the authors examined how clients' race/ethnicity and clinicians' professional and social characteristics affect their judgment of mental disorder among antisocially behaving youths. Vignettes described problematic behaviors meeting the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) criteria for conduct disorder but contained contextual information suggesting either disorder or nondisorder, following DSM-IV guidelines. Clinicians depended on contextual information to decide whether a mental disorder existed, and they judged White youths to have a disorder more frequently than Black or Hispanic youths. Clinicians' occupation, theoretical orientation, and age also were associated with disorder judgments, whereas their gender, race, and experience were not. Research and training implications of these variations in clinical judgments are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Avoiding the potential pitfalls of using negative priming tasks in developmental studies: Assessing inhibitory control in children, adolescents, and adults.

Despite being ignored, visual distractors often produce traceable negative priming (NP) effects that can be used to investigate inhibitory processes. Robust NP effects are typically found with young adults, but not with children. Using 2 different NP tasks, the authors compared NP in 5 different age groups spanning 5 to 25 years of age. The 1st task revealed comparable NP between all age groups, but a linear decrease in NP through childhood to early adulthood. In the 2nd task, NP decreased linearly into adulthood, with children actually showing larger NP than adults. This Age Group ? NP interaction was eliminated, however, when reaction time data were log transformed to control for age differences in overall processing speed. When appropriately transformed data were used, both experiments showed that NP was intact and comparable between children, adolescents, and adults, and suggested that an inhibitory process is fully developed by early childhood. The results highlight how potential pitfalls might be avoided when comparing NP in children and adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Higher cortical functions and the ego: Explorations of the boundary between behavioral neurology, neuropsychology, and psychoanalysis.

This article explores current thinking about brain organization and the potential bridging of various neuropsychological and psychoanalytic ideas. The focus is on the potentially vital, direct, and generally unappreciated connection of basic neuropsychological ideas to equally basic psychoanalytic constructs, particularly around concepts of drive, affect, and ego, and in terms of the corticolimbic, frontal-posterior, and lateral axes of brain organization. In terms of the corticolimbic axis, I suggest that Freud's basic model of the mind, in which the ego mediates between an internal drive milieu and perceptions of external reality, bears a remarkable resemblance to recent notions in behavioral neurology about the hierarchical organization of the cortex and the limbic system. In terms of the left-right lateral axis of organization, the affective (as opposed to more strictly cognitive) aspects of lateralization are linked to concepts suggesting right hemisphere cognitive processing in transference phenomena. Transference, although clinically complex, has consistent common denominators linking it with right hemisphere functions; it may be universal because it is neuropsychologically elemental. Empirical findings of right hemisphere involvement in affect may be due to the... (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential item functioning in a Spanish translation of the PTSD Checklist: Detection and evaluation of impact.

This study demonstrated the application of an innovative item response theory (IRT) based approach to evaluating measurement equivalence, comparing a newly developed Spanish version of the Posttraumatic Stress Disorder Checklist-Civilian Version (PCL-C) with the established English version. Basic principles and practical issues faced in the application of IRT methods for instrument evaluation are discussed. Data were derived from a study of the mental health consequences of community violence in both Spanish speakers (n = 102) and English speakers (n = 284). Results of differential item functioning (DIF) analyses revealed that the 2 versions were not fully equivalent on an item-by-item basis in that 6 of the 17 items displayed uniform DIF. No bias was observed, however, at the level of the composite PCL-C scale score, indicating that the 2 language versions can be combined for scale-level analyses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Why aggregated learning follows the power law of practice when individual learning does not: Comment on Rickard (1997, 1999), Delaney et al. (1998), and Palmeri (1999).

The power law of practice is often considered a benchmark test for theories of cognitive skill acquisition. Recently, P. F. Delaney, L. M. Reder, J. J. Staszewski, and F. E. Ritter (1998), T. J. Palmeri (1999), and T. C. Rickard (1997, 1999) have challenged its validity by showing that empirical data can systematically deviate from power-function fits. The main purpose of the present article is to extend their explanations in two ways. First, the authors empirically show that abrupt changes in performance are not necessarily based on a shift from algorithm to memory-based processing, but rather and more generally, that they occur whenever a more efficient task strategy is generated. Second, the authors show mathematically and per simulation that power functions can perfectly fit aggregated learning curves even when all underlying individual curves are discontinuous. Therefore, the authors question conclusions drawn from fits to aggregated data. (PsycINFO Database Record (c) 2011 APA, all rights reserved)