NMDAR hypofunction and somatostatin-expressing GABAergic interneurons and receptors: A newly identified correlation and its effects in schizophrenia
Publication date: June 2017 Source:Schizophrenia Research: Cognition, Volume 8 Author(s): Fatemah Alherz, Mohammad Alherz, Hashemiah Almusawi This review investigates the association between N-methyl-d-Aspartate receptor (NMDAR) hypofunction and somatostatin-expressing GABAergic interneurons (SST+) and how it contributes to the cognitive deficits observed in schizophrenia (SZ). This is based on evidence that NMDAR antagonists caused symptoms resembling SZ in healthy individuals. NMDAR hypofunction in GABAergic interneurons results in the modulation of the cortical network oscillation, particularly in the gamma range (...
Source: Schizophrenia Research: Cognition - March 9, 2017 Category: Psychiatry Source Type: research
Associations between daily living skills, cognition, and real-world functioning across stages of schizophrenia; a study with the Schizophrenia Cognition Rating Scale Japanese version
In this study, we sought to determine the validity of the Schizophrenia Cognition Rating Scale (SCoRS) Japanese version, an interview-based measure of cognition relevant to functional capacity (i.e. co-primary measure). For this purpose, we examined the relationship of SCoRS scores with performance on the Brief Assessment of Cognition in Schizophrenia (BACS) Japanese version, a standard neuropsychological test battery, and the Social and Occupational Functioning Assessment Scale (SOFAS), an interview-based social function scale. Subjects for this study (n=294) included 38 patients with first episode schizophrenia (FES), 13...
Source: Schizophrenia Research: Cognition - February 22, 2017 Category: Psychiatry Source Type: research
Is performance on probed serial recall tasks in schizophrenia related to duration of Attentional Blink?
This study tests the hypothesis that the working memory deficits in individuals with schizophrenia can be explained by slow processing of visual stimuli, as measured by the attentional blink (AB) task. Individuals with schizophrenia (SC) and controls (HC) were recruited from an early intervention service for psychosis and the local community. Data from 16 SC (11M/5F, mean=26.4yo) and 20 age-matched HC (11M/9F, mean=25.8yo) were analyzed. Each subject performed an AB task to determine their AB duration, defined as the lag to reach their plateau performance (ltpp). As expected, mean AB duration in the SC group (575ms) was si...
Source: Schizophrenia Research: Cognition - January 16, 2017 Category: Psychiatry Source Type: research
Neurological soft signs: Effects of trait schizotypy, psychological distress and auditory hallucination predisposition
This study highlights the importance of considering both trait and subclinical state risk factors when investigating risk for psychosis. (Source: Schizophrenia Research: Cognition)
Source: Schizophrenia Research: Cognition - December 23, 2016 Category: Psychiatry Source Type: research
Validating the construct of aberrant salience in schizophrenia — Behavioral evidence for an automatic process
Publication date: December 2016 Source:Schizophrenia Research: Cognition, Volume 6 Author(s): Teresa Katthagen, Felix Dammering, Norbert Kathmann, Jakob Kaminski, Henrik Walter, Andreas Heinz, Florian Schlagenhauf Suspecting significance behind ordinary events is a common feature in psychosis and it is assumed to occur due to aberrant salience attribution. The Salience Attribution Test (SAT; Roiser et al., 2009) measures aberrant salience as a bias towards one out of two equally reinforced cue features as opposed to adaptive salience towards features indicating high reinforcement. This is the first study to valida...
Source: Schizophrenia Research: Cognition - November 1, 2016 Category: Psychiatry Source Type: research
Compared to high and low cannabis use, moderate use is associated with fewer cognitive deficits in psychosis
Publication date: December 2016 Source:Schizophrenia Research: Cognition, Volume 6 Author(s): Ashley M. Schnakenberg Martin, Kelsey A. Bonfils, Beshaun J. Davis, Elizabeth A. Smith, Kelly Schuder, Paul H. Lysaker Literature on the relationship of cannabis use and cognition in schizophrenia provides the paradoxical view that cannabis use is sometimes linked with less severe impairment in neurocognition. This paper explored the possibility that this is a reflection of a dose related response between lifetime cannabis use and two forms of cognition, neurocognition and metacognition, in schizophrenia. It was hypothesiz...
Source: Schizophrenia Research: Cognition - October 10, 2016 Category: Psychiatry Source Type: research
Cognitive insight and functional outcome in schizophrenia; a multi-center collaborative study with the specific level of functioning scale –Japanese version
Publication date: December 2016 Source:Schizophrenia Research: Cognition, Volume 6 Author(s): Tomiki Sumiyoshi, Keiichiro Nishida, Hidehito Niimura, Atsuhito Toyomaki, Tsubasa Morimoto, Masayuki Tani, Ken Inada, Taiga Ninomiya, Hikaru Hori, Jun Manabe, Asuka Katsuki, Takamitsu Kubo, Yosuke Koshikawa, Masanao Shirahama, Kentaro Kohno, Toshihiko Kinoshita, Ichiro Kusumi, Akira Iwanami, Takefumi Ueno, Toshi Kishimoto, Takeshi Terao, Kazuyuki Nakagome The Specific Levels of Functioning Scale (SLOF) has been reported to provide a measure of social function in patients with schizophrenia. The aim of this ...
Source: Schizophrenia Research: Cognition - September 27, 2016 Category: Psychiatry Source Type: research
Disrupted latent inhibition in individuals at ultra high-risk for developing psychosis
In this study, 142 young people at ultra high-risk for developing psychosis and 105 controls were tested on a within-subject latent inhibition paradigm. Additionally, we later inquired about the strategy that each subject employed to complete the test, and further investigated the relationship between reported strategy and the extent of latent inhibition exhibited. Unlike controls, ultra high-risk subjects did not demonstrate a significant latent inhibition effect. This difference between groups became greater when controlling for strategy. The lack of latent inhibition effect in our ultra high-risk sample suggests that in...
Source: Schizophrenia Research: Cognition - August 16, 2016 Category: Psychiatry Source Type: research
Impaired retrieval processes evident during visual working memory in schizophrenia
Publication date: September 2016 Source:Schizophrenia Research: Cognition, Volume 5 Author(s): Peter A. Lynn, Seung Suk Kang, Scott R. Sponheim Prominent working memory (WM) deficits have been observed in people with schizophrenia (PSZ) across multiple sensory modalities, including the visuospatial realm. Electrophysiological abnormalities noted during early visual processing as well as later cognitive functions in PSZ may underlie deficiencies in WM ability, though the mechanisms linking behavior to neural responses are not well understood. WM dysfunction has also been observed in biological relatives of PSZ (REL) an...
Source: Schizophrenia Research: Cognition - August 15, 2016 Category: Psychiatry Source Type: research
Probability and magnitude evaluation in schizophrenia
Publication date: September 2016 Source:Schizophrenia Research: Cognition, Volume 5 Author(s): Matthew A. Albrecht, James A. Waltz, Michael J. Frank, James M. Gold Alterations in reinforcement learning and decision making in schizophrenia have been linked with orbitofrontal cortex (OFC) dysfunction, a region critical for weighing reward magnitude in the calculation of expected value (EV). However, much of this work has used complex tasks that require combined learning and EV calculation. Here we used a simple “Roulette” task that examined the calculation of EV directly through a combination of text and/or pictori...
Source: Schizophrenia Research: Cognition - August 15, 2016 Category: Psychiatry Source Type: research
Positive schizotypy and negative schizotypy are associated with differential patterns of episodic memory impairment
Publication date: September 2016 Source:Schizophrenia Research: Cognition, Volume 5 Author(s): Lili Sahakyan, Thomas R. Kwapil Cognitive impairment is a hallmark of schizophrenia; however, studies have not comprehensively examined such impairments in non-clinically ascertained schizotypic young adults. The present study employed a series of measures to assess episodic memory in high positive schizotypy, high negative schizotypy, and comparison groups (each group n =25). Consistent with diminished cognitive functioning seen in negative symptom schizophrenia, the negative schizotypy group exhibited deficits on free recal...
Source: Schizophrenia Research: Cognition - August 15, 2016 Category: Psychiatry Source Type: research
Validation of the cognitively normal range and below normal range subtypes in chronically hospitalized patients with schizophrenia
Conclusions There are neurocognitive subtypes of schizophrenia with differential illness characteristics comparable with the CNR and the BNR in patients of Han Chinese ethnicity with schizophrenia. (Source: Schizophrenia Research: Cognition)
Source: Schizophrenia Research: Cognition - August 15, 2016 Category: Psychiatry Source Type: research
Social cognition in patients at ultra-high risk for psychosis: What is the relation to social skills and functioning?
Conclusion Significant impairments in social cognition and social skills were found in UHR patients. The patients' social cognitive function was associated with overall functioning and social skills. Negative symptoms appear to play an important role for functioning. Research is needed to investigate how the relations between social cognition, social skills and functioning develop from the UHR state to the stage of manifest illness. Research into how deficits in social cognition and social skills can be ameliorated in UHR patients is warranted. (Source: Schizophrenia Research: Cognition)
Source: Schizophrenia Research: Cognition - August 15, 2016 Category: Psychiatry Source Type: research
Decoding emotion of the other differs among schizophrenia patients and schizoaffective patients: A pilot study
Publication date: September 2016 Source:Schizophrenia Research: Cognition, Volume 5 Author(s): Hagar Tadmor, Maya Levin, Tzameret Dadon, Meital E. Meiman, Alaa Ajameeh, Hosam Mazzawi, Amihai Rigbi, Ilana Kremer, Idit Golani, Alon Shamir The deficit in ability to attribute mental states such as thoughts, beliefs, and intentions of another person is a key component in the functional impairment of social cognition in schizophrenia. In the current study, we compared the ability of persons with first episode schizophrenia (FE-SZ) and individuals with schizophrenia displaying symptomatic remission (SZ-CR) to decode t...
Source: Schizophrenia Research: Cognition - August 15, 2016 Category: Psychiatry Source Type: research
Visual masking & amp; schizophrenia
Publication date: June 2015 Source:Schizophrenia Research: Cognition, Volume 2, Issue 2 Author(s): Michael H. Herzog, Andreas Brand Visual masking is a frequently used tool in schizophrenia research. Visual masking has a very high sensitivity and specificity and masking paradigms have been proven to be endophenotypes. Whereas masking is a powerful technique to study schizophrenia, the underlying mechanisms are discussed controversially. For example, for more than 25 years, masking deficits of schizophrenia patients were mainly attributed to a deficient magno-cellular system (M-system). Here, we show that there is v...
Source: Schizophrenia Research: Cognition - June 17, 2016 Category: Psychiatry Source Type: research
