Cognitive impairments associated with formal thought disorder in people with schizophrenia

Formal thought disorder (FTD), or disorganized speech, is one of the central signs of schizophrenia. Despite extensive research, the cognitive processes associated with FTD are still unclear. However, the authors' review of FTD theories and research indicates that considerable progress has been made in identifying possible cognitive impairments associated with FTD. Specifically, FTD is strongly associated with impaired executive functioning and with impaired processing of semantic information. Their review indicates that previous research has not yet supported an association between FTD and either an increase in spreading activation or an impairment within the language production system.     

Use of local public transport among people with cognitive impairments – A literature review

Being able to move around in the community including using different modes of transport is a prerequisite for being able to participate in activities outside home. This can be particular challenging for people with cognitive impairments. Still, research regarding public transport for people with cognitive impairments is scarce. In this narrative review scientific literature focusing on people with cognitive impairments and their needs in public transport, was identified and summarised. All aspects in the travel chain perspective were of interest. Literature search engines Scirus, Elin and Cinahl were used during the search.Thirty-four articles were included and analysed according to which part of the travel chain they covered in the used model. The results showed that the articles were unevenly allocated to the different parts of the model. Future studies based on real-world experiences are essential, and more user-centred approaches should be adopted. Moreover, there is a need for the development and evaluation of evidence-based rehabilitation. Finally, more research is needed to foster societal awareness of the problems and needs in the public transport of people with cognitive impairments taking the whole travel chain into consideration.     

Verbal processing deficits in schizophrenia

The authors reported that a subgroup of schizophrenic patients performed well on a tone serial position task but was impaired on an auditory word serial position task (Wexler, Stevens, Bowers, Cerniak, & Goldman-Rakic, 1998). This study assessed 30 schizophrenic and 32 controls (matched for comparable tone discrimination) on 4 versions of the verbal serial position tasks and 2 tone serial position tasks. Patients performed poorly on all verbal tasks but performed comparably to controls when tones served as stimuli. Proactive interference and visual presentation further compounded the verbal deficits. Deficits persisted with pronounceable nonword stimuli. These findings provide evidence of specific deficits in language-related processing, although the authors could not rule out the possibility that the differential effects that were observed between the tone and word tasks, and particularly among the verbal tasks, may result from differing discriminating power of the different tests.     

Extracting core components of cognitive control

The facility with which humans perform and shift among a wide variety of cognitive tasks seems to indicate a mechanism for entering into a task-dependent mode or set. However, little is known about the neural systems that subserve task control. A recent neuroimaging study by Dosenbach et al. offers a set of novel methodological tools to examine this issue and uncovers new candidate brain regions for a core system that might implement task sets.     

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.     

Working memory impairments in schizophrenia: a meta-analysis

Working memory (WM) deficit is a cardinal cognitive symptom of schizophrenia, but the differences among the tasks and measures used to assess WM make it difficult to compare across studies. The authors conducted a meta-analytic review to address 3 major questions: (a) Do patients with schizophrenia show WM deficits across diverse methodology; (b) Is WM deficit supramodal; and (c) Does the WM deficit worsen with longer delays? The results indicate that significant WM deficit was present in schizophrenia patients in all modalities examined. Increasing delay beyond 1 s did not influence the performance difference between schizophrenia patients and healthy control participants in WM. These results suggest that WM deficit in schizophrenia is modality independent and that encoding and/or early part of maintenance may be problematic.     

Trauma and posttraumatic stress disorder in people with schizophrenia

This study evaluated the hypothesis that trauma and posttraumatic stress disorder (PTSD) severity would be positively associated with schizophrenia symptoms. Forty-seven clients with schizophrenia were assessed for schizophrenia severity and for lifetime trauma history and PTSD symptoms in 2 independent symptom interviews; 35 (74%) participants reported at least 1 event in which there was threat of harm or life threat and subjective distress, and 6 (13%) had current PTSD. Trauma across the life span was associated with greater severity of PTSD. Within the total sample, PTSD symptoms were associated with greater emotional distress, but not with schizophrenia-specific symptoms. Distress among clients with schizophrenia and PTSD suggests the need for routine assessment of PTSD and development of PTSD interventions in this population.     

fMRI and cognitive dysfunction in schizophrenia

Despite being one of the most prevalent psychiatric conditions, SCHIZOPHRENIA is still poorly understood, with no clear objective biological marker. The advent of neuroimaging has enabled in vivo investigations to complement older techniques, and has revealed important insights. fMRI provides a means to assess the neurobiological theory that schizophrenia is caused by abnormal fronto-temporal lobe connections. In studies of language abnormalities, fMRI can explicitly assess the hypothesis that the normal lateralization of language is reversed in schizophrenia. Longitudinal fMRI studies, and studies examining the effects of medication, suggest that the technique has further potential to advance our understanding of this complex disorder.     

Face scanning distinguishes social from communication impairments in autism

How closely related are the social and communicative impairments in Autism Spectrum Disorder (ASD)? Recent findings in typically developing children suggest that both types of impairment are highly heritable but have only moderate behavioural and genetic overlap. So far, their respective roles in social perception are poorly understood. Here we show that when looking at other people’s faces, children with ASD who are better at socio‐emotional behaviours than non‐verbal communication look more at the eyes, while those with the opposite profile look more at the mouth (Study 1). For the mouth area, a similar pattern was observed for inverted faces, suggesting that information from this area is perceived on a featural basis. In Study 2, we found that when shown a person performing manual actions, ‘eye‐lookers’ from Study 1 tended to look most at the face of the actor, while ‘mouth‐lookers’ from Study 1 tended to look at the action itself (hand/objects). This result was found in both ASD and typical development. In Study 3, the main finding in Study 1 was replicated in a new sample. Taken together, we interpret these results as supporting the view that the neural systems underlying socio‐emotional versus non‐verbal communication skills are separable, a finding that has important theoretical and clinical implications. The results also suggest that a similar differentiation of looking behaviour may operate in normal development.     

Verbal and cognitive distractors in driving performance while using hands-free phones

This study investigated the effect of different types of distractions related to use of a hands-free phone on driving performance. The study used three types of verbal distractors: casual conversation, simple arithmetic number guessing, and number adding, in the phone conversation. 12 adults were instructed to follow a lead vehicle on a closed-course highway in a fixed-based driving simulator. The results showed that use of a hands-free cellular phone involving verbal and cognitive distractions impaired driving performance and skill. Types of distraction produced significantly different effects on several dependent variables: the driving speed, headway (distance between the lead car and the manipulated car), brake reaction time, and number of collisions with the lead car. In general, the higher the cognitive load involved in the dialogue, the worse the driving performance.     

Neuropsychological impairments in schizophrenia: Integration of performance-based and brain imaging findings

Until recently, the dominant view was that schizophrenia patients have limited, if any, neuropsychological impairments, and those that are observed are only secondary to the florid symptoms of the disorder. This view has dramatically changed. This review integrates recent evidence demonstrating the severity and profile of neuropsychological impairments in schizophrenia. We present quantitative evaluation of the literature demonstrating that the most severe impairments are apparent in episodic memory and executive control processes, evident on a background of a generalized cognitive deficit. The neuropsychological impairments potentially represent genetic liability to the disorder, as similar, yet milder, impairments are evident in schizophrenia patients even before the onset of psychotic symptoms, as well as in the nonpsychotic relatives of schizophrenia patients. Corresponding cognitive neuroimaging literature on executive functions, episodic memory, and working memory in schizophrenia documenting abnormalities in frontal and medial temporal lobes is summarized, and current models integrating neuropsychological and neuroimaging data are discussed.     

An innovative approach to clinical communication in schizophrenia: the approaches to schizophrenia communication checklists

Side effects from antipsychotic medications can have a profound effect on patients' lives and may adversely affect their willingness to comply with treatment. Identification of side effects through improved communication between psychiatrists, other members of the healthcare team, and their patients might increase treatment compliance. The Approaches to Schizophrenia Communication (ASC) Steering Group developed two simple, practical checklists for use in the busy clinical setting. The ASC-Self-Report (ASC-SR) checklist is completed by the patient and comprises a list of the more common or clinically important side effects of antipsychotic treatment. The ASC-Clinic (ASC-C) checklist is completed by both clinician and patient together, being used as the basis for a semi-structured interview. In a multicenter pilot study set up to evaluate the utility of checklists, 86% of patients responding considered the ASC-SR to be useful in communicating their problems to psychiatrists and other members of the healthcare team. All healthcare team respondents found both checklists to be helpful when discussing side effect problems with their patients. Moreover, 41% and 47% of healthcare team respondents reported that the ASC-SR and ASC-C, respectively, had assisted them in identifying side-effect problems not previously acknowledged. Preliminary evaluation of the ASC-SR and ASC-C in this multicenter pilot study suggests that both tools were user-friendly, encouraged communication between patients and healthcare professionals about antipsychotic drug side effects, and could readily integrated into everyday clinical practice.     

The impact of threat and cognitive stress on speech motor control in people who stutter

PurposeIn the present study, an Emotional Stroop and Classical Stroop task were used to separate the effect of threat content and cognitive stress from the phonetic features of words on motor preparation and execution processes.MethodA group of 10 people who stutter (PWS) and 10 matched people who do not stutter (PNS) repeated colour names for threat content words and neutral words, as well as for traditional Stroop stimuli. Data collection included speech acoustics and movement data from upper lip and lower lip using 3D EMA.ResultsPWS in both tasks were slower to respond and showed smaller upper lip movement ranges than PNS. For the Emotional Stroop task only, PWS were found to show larger inter-lip phase differences compared to PNS. General threat words were executed with faster lower lip movements (larger range and shorter duration) in both groups, but only PWS showed a change in upper lip movements. For stutter specific threat words, both groups showed a more variable lip coordination pattern, but only PWS showed a delay in reaction time compared to neutral words. Individual stuttered words showed no effects. Both groups showed a classical Stroop interference effect in reaction time but no changes in motor variables.ConclusionThis study shows differential motor responses in PWS compared to controls for specific threat words. Cognitive stress was not found to affect stuttering individuals differently than controls or that its impact spreads to motor execution processes.Educational objectives: After reading this article, the reader will be able to: (1) discuss the importance of understanding how threat content influences speech motor control in people who stutter and non-stuttering speakers; (2) discuss the need to use tasks like the Emotional Stroop and Regular Stroop to separate phonetic (word-bound) based impact on fluency from other factors in people who stutter; and (3) describe the role of anxiety and cognitive stress on speech motor processes.     

Self-consciousness impairments in schizophrenia with and without first rank symptoms using the moving rubber hand illusion

IntroductionThe moving rubber hand illusion allows the evaluation both the sense of body ownership and agency using visuo-motor stimulations.MethodsWe used the moving rubber hand illusion in anatomic congruence with explicit measures to compare active asynchronous and passive synchronous movements in patients diagnosed with schizophrenia with first rank symptoms (FRS) (n = 31) versus without FRS (n = 25).ResultsPatients with FRS are characterized by a lack of agency in active asynchronous condition. The two groups had no sense of ownership in synchronous passive condition. Using a multivariate regression model, we found an association between agency and body ownership measures in the active asynchronous condition in two groups (OR: 1.825, p < 0.001). In the passive condition, this association was only present in the group with first rank symptoms (OR: 2.04, p < 0.001).ConclusionTemporal proximity and sensorimotor information are essential in the understanding of self-consciousness disorders in schizophrenia.     

The effect of age of acquisition on older individuals with and without cognitive impairments

The present study compared the effects of age of acquisition (AoA) on object naming across groups of older individuals with cognitive impairments, healthy older controls, and young healthy controls. All participants named a set of 80 pictures, within which both AoA and frequency were manipulated orthogonally. Early-acquired objects were named faster than late-acquired objects across all groups. Response time also declined with age and with cognitive impairment between the groups. The effect of AoA differed across groups, with AoA effects being largest for the older group with cognitive impairments and smallest for the young control group. The present study adds strength to the suggestion that AoA of picture names is one of the factors that influence survival or loss of memories in dementia and cognitive decline, and this could therefore be used as a potential screening test for cognitive impairment disorders in the future.     

语言转换对非熟练双语者不同认知控制成分的即时影响

语言转换情境是否影响非熟练双语者的认知控制存在争议。实验1和实验2分别采用不同的实验范式探讨语言转换对非熟练双语者的认知控制是否会有即时的影响, 以及对不同认知控制成分的影响是否会有不同。结果表明, 语言转换情境能够即时地促进反应抑制, 阻碍干扰抑制, 但对认知灵活性没有影响, 同时说明了反应抑制、干扰抑制和认知灵活性属于3种不同的认知成分, 其内在作用机制不同。此外, 研究结果还进一步说明了双语者的认知控制优势是双语者长期双语使用的结果, 为双语优势的内在机制提供了实验支持。     

Odor identification impairments in schizophrenia: relationship with demographic measures, clinical variables, and diagnostic subtypes

Smell identification deficits are consistently found in schizophrenia (SZ), but little is known about the nature and characterization of this deficit or its relationship to the phenomenology of the illness. This study aims to further delineate smell identification errors in SZ by examining the relationship of patient demographic differences with smell-identification performance. Our results showed that a patient's gender and education were related to odor-identification scores, with better performance seen in female patients and in those with greater educational attainment. However, there was no effect related to age, ethnicity, or socioeconomic status on odor identification. A smell identification deficit was also unrelated to clinical characteristics of the patients, including age at first hospitalization, number of psychiatric hospitalizations, and duration of illness. Odor identification also did not differ by SZ subtype, nor between SZ and schizoaffective disorder patients. These findings emphasize that odor identification deficits in SZ are unrelated to clinical illness features, cannot be explained by other confounds related to olfaction in the general population, and may be core features related to the SZ disease process.