Attention In Schizophrenia Research Articles

Pre-stimulus EEG phase coherence predicts visual target detection failures in schizophrenia: A pilot study

Impaired visual target detection is a common finding in schizophrenia that is linked to poor functional outcomes. However, the neural mechanisms that contribute to this deficit remain unclear. Recent research in healthy samples has identified relationships between the phase of pre-stimulus electroencephalographic (EEG) activity in the alpha band (8-12 Hz) or theta band (4-7 Hz) and the likelihood of visual target detection with and without attentional cueing, but these effects have not yet been explored in schizophrenia. We performed a study to investigate such effects in schizophrenia (n = 19) and healthy participants (n = 14), using a visual target detection task with attentional cues. We found significant relationships between pre-stimulus EEG phase properties and visual target detection in both groups, but also clear differences in the effects as a function of frequency, group, and attentional cueing. Alpha-band phase effects were relatively uniform across groups and conditions. By contrast, theta-band phase effects showed differences by group and attentional condition which could be consistent with attentional hyperfocusing in the schizophrenia group. Thus, our results elucidate a novel neural mechanism that may help to explain known impairments affecting both visual target detection and attention in schizophrenia.

Pre-saccadic shifts of attention in individuals diagnosed with schizophrenia.

Pathophysiological theories of schizophrenia (SZ) symptoms posit an abnormality in using predictions to guide behavior. One such prediction is based on imminent movements, via corollary discharge signals (CD) that relay information about planned movement kinematics to sensory brain regions. Empirical evidence suggests a reduced influence of sensorimotor predictions in individuals with SZ within multiple sensory systems, including in the visual system. One function of CD in the visual system is to selectively enhance visual sensitivity at the location of planned eye movements (pre-saccadic attention), thus enabling a prediction of the to-be-foveated stimulus. We expected pre-saccadic attention shifts to be less pronounced in individuals with SZ than in healthy controls (HC), resulting in unexpected sensory consequences of eye movements, which may relate to symptoms than can be explained in the context of altered allocation of attention. We examined this question by testing 30 SZ and 30 HC on a pre-saccadic attention task. On each trial participants made a saccade to a cued location in an array of four stimuli. A discrimination target that was either congruent or incongruent with the cued location was briefly presented after the cue, during saccade preparation. Pre-saccadic attention was quantified by comparing accuracy on congruent trials to incongruent trials within the interval preceding the saccade. Although SZs were less accurate overall, the magnitude of the pre-saccadic attention effect generally did not differ across groups nor show a convincing relationship with symptom severity. We did, however, observe that SZ had reduced pre-saccadic attention effects when the discrimination target (probe) was presented at early stages of saccade planning, when pre-saccadic attention effects first emerged in HC. These findings suggest generally intact pre-saccadic shifts of attention in SZ, albeit slightly delayed. Results contribute to our understanding of altered sensory predictions in people with schizophrenia.

Neural indicators of initial control rather than early maintenance of attention predict impaired visual attention in schizophrenia.

Attentional filtering has long been suggested to be a core deficit of schizophrenia. Recent work has emphasized the important distinction between attentional control, which involves the voluntary selection of a particular stimulus for focused processing, and implementation of selection, which involves the mechanisms that actually enhance the stimulus selected via filtering processes. We recorded electroencephalography data from people with schizophrenia (PSZ), their first-degree relatives (REL) and healthy controls (CTRL) during performance of a resistance to attentional capture task that tapped attentional control and implementation of selection measured during a brief period of attentional maintenance. Event-related potentials (ERPs) during attentional control and maintenance of attention revealed diminished neural responding in PSZ. ERPs during attentional control predicted performance on the visual attention task for PSZ, but not for REL and CTRL. Visual attention performance for CTRL was best predicted by ERPs during attentional maintenance. These results support the idea that poor initial voluntary attentional control is more central to attentional dysfunction in schizophrenia than difficulty implementing selection (e.g., maintaining attention). Nevertheless, weak neural modulations indicative of impaired early attentional maintenance in PSZ challenge notions of increased intensity of focus or "hyperfocusing" in the disorder. Improvement of the initial control of attention may be a productive target for cognitive remediation interventions for schizophrenia. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Sexual needs of people with schizophrenia: a descriptive phenomenological study

BackgroundSexual health is one of the main areas of health and basic human rights which has been paid less attention in schizophrenia. Most studies have focused on sexual dysfunction rather than the sexual needs of people with schizophrenia. This study explores the sexual needs of people with schizophrenia and identify factors hindering sexual activities.MethodsWe carried out a qualitative study using a descriptive phenomenological approach. Data were collected at a psychiatric hospital in China. In total, 20 patients with schizophrenia were recruited through purposive sampling. Face to face semi-structured in-depth interviews were conducted with them. Interview recordings were transcribed by the research team, and transcripts were analyzed by two independent coders with Colaizzi’s descriptive analysis framework by using NVivo 11 software. The consolidated criteria for reporting qualitative research checklist was used for reporting.ResultsThe data analysis revealed 10 subthemes categorized into 3 macro themes: (1) multiple barriers hinder sexual activity; (2) significance of sex; and (3) conditions for fulfilling sexual needs.ConclusionA poor sexual quality of life may be found in patients with schizophrenia. Furthermore, people with schizophrenia did not lose interest in maintaining an active sex life. Mental health services should address this issue in three areas: sexual knowledge, sexual space, and sexual objects.

Limited Consistency and Strength of Neural Oscillations During Sustained Visual Attention in Schizophrenia

BackgroundNeural oscillations support perception, attention, and higher-order decision making. Aberrations in the strength or consistency of these oscillations in response to stimuli may underlie impaired visual perception and attention in schizophrenia. Here, we examined the phase and power of alpha oscillations (8–12 Hz) as well as aspects of beta and theta frequency oscillations during a demanding visual sustained attention task. MethodsPatients with schizophrenia (n = 74) and healthy control participants (n = 68) completed the degraded stimulus continuous performance task during electroencephalography. We used time-frequency analysis to evaluate the consistency (intertrial phase coherence) of the alpha cycle shortly after stimulus presentation (50–250 ms). For oscillation strength, we examined event-related desynchronization in a later window associated with decision making (360–700 ms). ResultsAlpha intertrial phase coherence was reduced in schizophrenia, and similar reductions were observed in theta (4–7 Hz) and beta (13–20 Hz), suggesting a lack of responsiveness in slower oscillations to visual stimuli. Alpha and beta event-related desynchronization were also reduced in schizophrenia and associated with worse task performance, increased symptoms, and poorer cognition, suggesting that limited responsiveness of oscillations is related to impairments in the disorder. Individuals with lower intertrial phase coherence had slower resting-state alpha rhythms consistent with dysfunctional oscillations persisting across default and task-related brain states. ConclusionsIn schizophrenia, abnormalities in the phase consistency and strength of slower oscillations during visual perception are related to symptoms and cognitive functioning. Altered visual perception and impaired attention in the disorder may be the consequence of aberrant slower oscillations that fail to dynamically reset and modulate in response to stimuli.

Supplemental Material for Neural Indicators of Initial Control Rather Than Early Maintenance of Attention Predict Impaired Visual Attention in Schizophrenia

Supplemental Material for Neural Indicators of Initial Control Rather Than Early Maintenance of Attention Predict Impaired Visual Attention in Schizophrenia

The Flickering Spotlight of Visual Attention: Characterizing Abnormal Object-Based Attention in Schizophrenia

The Flickering Spotlight of Visual Attention: Characterizing Abnormal Object-Based Attention in Schizophrenia

The flickering spotlight of visual attention: Characterizing abnormal object-based attention in schizophrenia

Schizophrenia is associated with deficits in both object perception and visual attention. However, few studies in schizophrenia have investigated object-based attention, which is dissociable from other forms of visuospatial attention. Recent research in healthy populations has shown that the ‘spotlight’ of sustained visual attention flickers in a rhythmic, oscillatory fashion at specific frequencies in the 4-12 Hz range. In healthy samples, this oscillatory signature has been used to investigate spatiotemporal dynamics of object-based attention, showing that the attentional spotlight spreads to uncued locations within cued objects, and also periodically alternates focus between cued and uncued objects. In this study, we adapted a performance-based visual object cueing task to investigate object-based attention in individuals with a schizophrenia diagnosis and healthy controls. In controls, spatiotemporal patterns of object-based attention closely resembled those reported in previous studies of healthy individuals. In the schizophrenia group, the oscillatory signature of attention also appeared in the location of the cue and on uncued objects, similar to the effects in controls. Indeed, the oscillatory signature of attention at the spatial location of the cue was stronger in the schizophrenia group than in controls. However, attention did not spread across the cued object in schizophrenia; rather, attention appeared to remain hyperfocused at the spatial location of the cue. These findings provide the first evidence that visual attention has oscillatory characteristics in schizophrenia, as in the general population. The results also show that the fundamental process of attentional spreading which underlies object-based attention is abnormal in schizophrenia.

Intact differentiation of responses to socially-relevant emotional stimuli across psychotic disorders: An event-related potential (ERP) study

Event-related potential (ERP) studies of motivated attention in schizophrenia typically show intact sensitivity to affective vs. non-affective images depicting diverse types of content. However, it is not known whether this ERP pattern: 1) extends to images that solely depict social content, (2) applies across a broad sample with diverse psychotic disorders, and (3) relates to self-reported trait social anhedonia. We examined late positive potential (LPP) amplitudes to images involving people that were normatively pleasant (affiliative), unpleasant (threatening), or neutral in 97 stable outpatients with various psychotic disorders and 38 healthy controls. Both groups showed enhanced LPP to pleasant and unpleasant vs. neutral images to a similar degree, despite lower overall LPP in patients. Within the patients, there were no significant LPP differences among subgroups (schizophrenia vs. other psychotic disorders; affective vs. non-affective psychosis) for the valence effect (pleasant/unpleasant vs. neutral). Higher social anhedonia showed a small, significant relation to lower LPP to pleasant images across all groups. These findings suggest intact motivated attention to social images extends across psychotic disorder subgroups. Dimensional transdiagnostic analyses revealed a modest association between self-reported trait social anhedonia and an LPP index of neural sensitivity to pleasant affiliative images.

Attention in Schizophrenia.

Attention is clearly a core area of cognitive dysfunction in schizophrenia, but the concept of "attention" is complex and multifaceted. This chapter focuses on three different aspects of attentional function that are of particular interest in schizophrenia. First, we discuss the evidence that schizophrenia involves a reduction in global alertness, leading to an inward focusing of attention and a neglect of external stimuli and tasks. Second, we discuss the control of attention, the set of processes that allow general goals to be translated into shifts of attention toward task-relevant information. When a goal is adequately represented, people with schizophrenia often show no deficit in using the goal to direct attention in the visual modality unless challenged by stimuli that strongly activate the magnocellular processing pathway. Finally, we discuss the implementation of selection, the processes that boost relevant information and suppress distractors once attention has been directed to a given source of information. Although early evidence indicated an impairment in selection, more recent evidence indicating that people with schizophrenia actually focus their attention more narrowly and more intensely that healthy individuals (hyperfocusing). However, this hyperfocused attention may be directed toward goal-irrelevant information, creating the appearance of impaired attentional filtering.

N-methyl-d-aspartate receptor antagonism modulates P300 event-related potentials and associated activity in salience and central executive networks

Impairments in auditory information processing in schizophrenia as indexed electrophysiologically by P300 deficits during novelty (P3a) and target (P3b) processing are linked to N -methyl- D -aspartate receptor (NMDAR) dysfunction. This study in 14 healthy volunteers examined the effects of a subanesthetic dose of the NMDAR antagonist ketamine on P300 and their relationship to psychomimetic symptoms and cortical source activity (with eLORETA). Ketamine reduced early (e- P3a) and late (l-P3a) novelty P300 at sensor (scalp)-level and at source-level in the salience network. Increases in dissociation symptoms were negatively correlated with ketamine-induced P3b changes, at sensor-level and source-level, in both salience and central executive networks. These P3a alterations during novelty processing, and the symptom-related P3b changes during target processing support a model of NMDAR hypofunction underlying disrupted auditory attention in schizophrenia.

Divided Attention in Schizophrenia: A Dual Task Paradigm

Abstract Schizophrenia is known to be associated with attentional deficits. Few studies have examined whether the disorder is also associated with a deficit in the ability to divide attention, and they have given contradictory results. Some have reported that patients show greater loss of performance than healthy controls when moving from single tasks to dual tasks, and others have reported that performance loss is similar in both groups or even that patients perform the dual task better than either task on its own. To help resolve this controversy, we performed a first study in which we designed a dual task paradigm with a group of 36 healthy participants. This dual task involves 2 tasks of equivalent difficulty that make use of different sensory modalities. In the second study, we gave this dual task to 23 patients with schizophrenia and 25 healthy participants. Both groups decreased similarly their performance in dual tasks, but the patients showed lower baseline performance in the single task. Our findings suggest that patients with schizophrenia and healthy participants use similar strategies to divide their attention, but in a high-degrading stimuli condition patients perform below the controls in a single task.

Schizotypy is associated with difficulty maintaining multiple hypotheses.

Among neurocognitive accounts of delusions, there is a growing consensus that it is the certainty with which delusions are held, rather than their content that defines some beliefs as delusional. On a continuum model of psychosis, this inappropriate certainty ought to be present (albeit in an attenuated form) in healthy adults who score highly in schizotypy. It was hypothesised that this might be most evident in circumstances where the environment provides incomplete or probabilistic information, which thereby forces the participant to hold two imperfectly supported, concurrent hypotheses in mind. A cued visual search task was used to measure people's capacity to use partially predictive information (i.e., a cue that predicted the target may occur in one of the two locations) to facilitate speeded responding. As hypothesised, people's performance on the trials that required holding two hypotheses in mind concurrently was significantly and specifically associated with the positive components of schizotypy. This finding is consistent with a hyperfocusing of attention in schizophrenia, and may help explain why delusion-prone individuals have a tendency to "jump to conclusions" or be resistant to disconfirming information when faced with multiple, partially supported hypotheses.

Lateralized evoked responses in parietal cortex demonstrate visual short-term memory deficits in first-episode schizophrenia

Working memory dysfunction may be central to neurocognitive deficits in schizophrenia. Maintenance of visual information in working memory, or visual short-term memory (vSTM), is linked to general cognitive dysfunction and predicts functional outcome. Lateralized change-detection tasks afford investigation of the contralateral delay activity (CDA), a useful tool for investigating vSTM dysfunction. Previous work suggests “hyperfocusing” of attention in schizophrenia, such that CDA is increased when a single item is maintained in vSTM but reduced for multiple items. If observed early in the disease, vSTM dysfunction may be a key feature of schizophrenia or target for intervention. We investigated CDA during lateralized vSTM of one versus three items using sensor-level electroencephalography and source-level magnetoencephalography in 26 individuals at their first episode of schizophrenia-spectrum psychosis (FESz) and 26 matched healthy controls. FESz were unable to modulate CDA with increased memory load – high-load CDA was reduced and low-load CDA was increased compared to controls. Further, sources of CDA in posterior parietal cortex were reduced in FESz and indices of working memory were correlated with neurocognitive deficits and symptom severity. These results support working memory maintenance dysfunction as a central and early component to the disorder. Targeted intervention focusing on vSTM deficits may be warranted to alleviate downstream effects of this disability.

Attention in schizophrenia: Impaired inhibitory control, faulty attentional resources, or both?

While the literature regarding the existence of difficulties in inhibition in schizophrenia is relatively consistent, it is not clear whether these difficulties reflect any specific deficit in an inhibitory control process or whether they are the result of deficits in the systems that regulate inhibitory control, such as attentional resources. This also raises the issue of attentional resources in schizophrenia, which offers a somewhat puzzling and sometimes contradictory picture. In this study, these issues were investigated by means of a paradigm in which the need for inhibitory control and the need for correct allocation of attentional resources varied parametrically. Twenty-six outpatients with a diagnosis of schizophrenia and 26 matched controls completed a visual search task during which distractors were presented and had to be inhibited. At the same time, they also completed an auditory target detection task of varying difficulty. The results show that the patients had difficulties both in inhibiting distractors and in correctly allocating attention to the two tasks. The results also show that these two difficulties were not related. This leads to the conclusion that schizophrenia involves both defective inhibitory control and faulty management of attentional resources, and that the former does not result from the latter. Furthermore, these effects seem to be neither dependent on processing speed, nor related to medication.

White Matter Microstructural Properties Associated with Impaired Attention in Chronic Schizophrenia: A Multi-Center Study

Attention as a key cognitive function is impaired in schizophrenia, interfering with the normal daily life of the patients. Previous studies on the microstructural correlates of attention in schizophrenia were limited to single fibers, did not include a control group, or did not adjust for drug dosage. In the current study, we investigated the association between microstructural properties of the white matter fibers and attention tests in 81 patients and 79 healthy controls from the Mind Clinical Imaging Consortium database. Integrity measures of superior longitudinal fasciculus, cingulum, genu, and splenium were extracted after tractography. Using an interaction model between diagnosis and microstructural properties, and adjusting for age, gender, acquisition site, education, and cumulative drug usage dose, and after correcting for family-wise error, we showed decreased integrity in the patients and a significant negative association between fractional anisotropy of the tracts and trail making test part A with a greater expected decrease in the attention per unit of decrease of integrity in the patients compared to the healthy controls. Our findings suggest that decreased integrity of the bilateral cingulum, and splenium, are independent of the cumulative drug dosage, age, gender, and site, and may underlie the impaired attention in the schizophrenia.

S188. VISUAL ATTENTION IN EARLY-ONSET SCHIZOPHRENIA AND OTHER NEURODEVELOPMENTAL DISORDERS: THE IMPACT OF SPEAKING WHILE LOOKING AT PICTURES OF SOCIAL INTERACTIONS – EVIDENCE FROM EYE TRACKING DATA

BackgroundVisual attention in Schizophrenia (SZ) differs from that of neuro-typical controls, and scan-path abnormalities have been proposed as a robust marker of the disorder (Nishiura et al., 2007). In free viewing paradigms, a restricted area of visual exploration has been reported as a robust atypical finding in SZ participants across a variety of depicted contents (Beedie et al., 2011), and has been shown to be a highly efficient discriminator between SZ and healthy controls (Benson et al., 2012). Moreover, speaking about what one sees during the act of looking has been shown to impact visual exploration behavior (Klein et al., 2014). Finally, despite clinical and genetic-biological relationships between schizophrenia, autism and ADHD (Owen & O’Donovan, 2017) there is, to our knowledge, yet no direct comparison between these neurodevelopmental disorders using eye tracking. The “head-to-head” comparison is the primary objective of this study.MethodsWe tested four groups of adolescent and young adults, namely early-onset Schizophrenia (SZ, N=21, 15 males, mean age ± 1 standard deviation 19.7±1.7 years), Attention Deficit Hyperactivity Disorder (ADHD, N=28, 15 males, 19.9±1.4 years), Autism (ASD, N=26, 25 males, 19.7±1.9 years), and typical controls (TD, N= 29, 12 males, 19.8±1.6 years). The ocular-motor task battery comprised of different free viewing tasks including free viewing of different kinds of social interactions in static pictures whilst solely viewing versus viewing-plus speaking (in counterbalanced order). Eye movements were recorded with 1.000Hz using the EyeLink 1000+ system and analyzed with Data Viewer Eyelink Software and MATLAB (Version R2017a, Mathworks, USA). Statistical Analysis was performed in SPSS Statistics 2.3 (IBM, USA).ResultsVisual attention of SZ patients manifested significant less gaze scatter than TD whilst merely looking at the images. During looking and speaking, however, the two groups had a similar spatial scatter of fixations. Preliminary analyses indicate that participants with ADHD and ASD did not differ from TD in this measure.DiscussionConstraint gaze scatter in visual exploration is a robust and discriminating finding in schizophrenia that has been associated with the negative symptomatology of the disorder. The present results confirm our previous findings (Klein et al., 2014) and suggest that the act of speaking may partially counteract and compensate the restricted visual scanning performed by SZ participants, thus contributing to a better understanding of Visual Attention in SZ and its differentiation from other neurodevelopmental disorders.

T227. VIRTUAL REALITY SOCIAL SKILLS TRAINING IMPROVES SOCIAL ATTENTION IN INDIVIDUALS WITH SCHIZOPHRENIA

BackgroundSocial impairment is a core feature of schizophrenia presenting a major barrier to recovery. Although antipsychotic medications can reduce psychotic symptoms, social impairments often persist, contributing to poor outcome. Validated interventions, such as Social Skills Training (Bellack et al., 2004), target a broad range of social domains but they yield only modest effect sizes for social outcome (Pfammatter et al, 2006). Moreover, conventional social interventions suffer from high burden on the clients and therapists, low adherence, lack of personalization, and low generalizability. Importantly, social interventions are not widely available. Virtual reality (VR) offers a viable alternative to conventional therapies with several advantages including high acceptability, an extensive repertoire of stimuli, low-burden, low-cost and safety (Strickland, 1997). Importantly, VR allows for a precise targeting of social cognitive mechanisms. Social attention, the fast orientation and allocation of resources to social stimuli can be indexed by tracking eye movements. Abnormal eye scanning behavior during social interactions has been linked to poor social functioning in schizophrenia (Brunet-Gouet & Decety, 2006). We designed a VR-based social skills training game to directly target social attention in schizophrenia.MethodsEighteen individuals with schizophrenia (SZ) participated in the VR training game twice a week for 5 weeks. Eye movement patterns were recorded throughout the training. Subjects were required to solve social “missions” (e.g., obtain personal information through conversations with avatars) in different naturalistic scenarios. To start a mission, participants had to fixate on the chosen avatar. The latency to engage in a social interaction was indexed by the fixation time (social engagement latency). Each session consisted of 12 missions. We compared social engagement latency and eye gaze patterns pre- and post-training to assess the efficacy of the VR social skills training program.ResultsSocial engagement latency significantly decreased after 10 sessions (d=0.78). This result suggests that prosocial attention benefitted from VR training. We also found that the standard deviation of dwell time (i.e., proportion of time spent looking at the avatar’s face during a conversation) significantly increased across training sessions (d=0.56). This result suggests an increased modulation of interpersonal engagement during social interaction. Additionally, participants’ emotion recognition ability significantly increased (η2 = 0.27), and negative symptoms significantly decreased (η2=0.34) from pre- to post- training. Importantly, these changes in social attention correlated with improvement in negative symptoms.DiscussionSimulated and targeted social interactions with avatars in VR significantly improved social attention in individuals with schizophrenia. Importantly, improvements in negative symptoms and emotion perception after training suggest that this training protocol has an impact on a broad range of social functions. VR training is a promising alternative to traditional psychosocial interventions to target specific mechanisms underlying social functioning in schizophrenia.

Superficial Retinal Vascular Abnormalities in Schizophrenia as Shown by Swept Source OCT-Angiography: A Preliminary Study

Altered microvasculature is central to the pathophysiology of many CNS disorders, but it has received less attention in schizophrenia. Since retinal and cerebral microvessels are homologous in structure/function, the retina can be used as a window into the brain. Studies using fundus imaging in schizophrenia have identified decreased arteriole diameter and tortuosity, as well as increased venule diameter and tortuosity. Herein, we explore the ability of optical coherence tomography angiography (OCTA) to identify fine retinal vessel alterations in schizophrenia.

In the eye of the beholder? Oxytocin effects on eye movements in schizophrenia

BackgroundIndividuals with schizophrenia have difficulty in extracting salient information from faces. Eye-tracking studies have reported that these individuals demonstrate reduced exploratory viewing behaviour (i.e. reduced number of fixations and shorter scan paths) compared to healthy controls. Oxytocin has previously been demonstrated to exert pro-social effects and modulate eye gaze during face exploration. In this study, we tested whether oxytocin has an effect on visual attention in patients with schizophrenia. MethodsNineteen male participants with schizophrenia received intranasal oxytocin 40UI or placebo in a double-blind, placebo-controlled, crossover fashion during two visits separated by seven days. They engaged in a free-viewing eye-tracking task, exploring images of Caucasian men displaying angry, happy, and neutral emotional expressions; and control images of animate and inanimate stimuli. Eye-tracking parameters included: total number of fixations, mean duration of fixations, dispersion, and saccade amplitudes. ResultsWe found a main effect of treatment, whereby oxytocin increased the total number of fixations, dispersion, and saccade amplitudes, while decreasing the duration of fixations compared to placebo. This effect, however, was non-specific to facial stimuli. When restricting the analysis to facial images only, we found the same effect. In addition, oxytocin modulated fixation rates in the eye and nasion regions. DiscussionThis is the first study to explore the effects of oxytocin on eye gaze in schizophrenia. Oxytocin had enhanced exploratory viewing behaviour in response to both facial and inanimate control stimuli. We suggest that the acute administration of intranasal oxytocin may have the potential to enhance visual attention in schizophrenia.