scholarly journals Systematic review: the relationship between sleep spindle activity with cognitive functions, positive and negative symptoms in psychosis

2020 ◽  
Vol 2 ◽  
pp. 100025
Author(s):  
Chi Hung Au ◽  
Christopher-James Harvey
1986 ◽  
Vol 1 (2) ◽  
pp. 108-122 ◽  
Author(s):  
Nancy C. Andreasen ◽  
William M. Grove

SummaryMost investigators concur that schizophrenia is probably a heterogeneous group of disorders that share the common features of psychotic symptoms, partial response to neuroleptics, and a relatively poor outcome. The subdivision of schizophrenia into two subtypes, positive versus negative, has achieved wide acceptance throughout the world during recent years. This distinction has heuristic and theoretical appeal because it unites phenomenology, pathophysiology, and etiology into a single comprehensive hypothesis.In spite of its wide appeal, the distinction has a number of problems. These include the failure to distinguish between symptom syndromes and diseases; failure to deal with the mixed patient; failure to take longitudinal course into account; and failure to address conceptually and methodologically the distinction between positive and negative symptoms.This paper focuses primarily on the conceptual basis for two instruments designed to measure positive and negative symptoms, the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS), originally described in 1982. Since their description, these scales have been used in a variety of other centers. These scales are based on the hypothesis that negative symptoms represent a deficit or diminution in normal psychological functions wliile positive symptoms represent an excess or distortion of normal functions. Reliability data are now available from Italy, Spain, and Japan which suggest that these scales can be used reliably in cultural settings outside the United States. The results of these studies are summarized in this paper. In addition, a replication study involving a new sample of 117 schizophrenics collected at the University of Iowa is described. In this second study of the SANS and SAPS, internal consistency is found to be quite high in the SANS. Thus negative symptoms appear to be more internally correlated with one another than are positive symptoms. The implications of this result are discussed. A principal components analysis is used to explore the relationship between positive and negative symptoms. While the study reported in 1982 suggested that positive and negative symptoms are negatively correlated, in the present study they appear to be uncorrelated. Overall, the results suggest that the SANS and SAPS are useful comprehensive instruments for the evaluation of positive and negative symptoms. The relationship between these symptoms and external validators such as cognitive functioning or CT scan abnormalities will be reported in a subsequent investigation.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 868
Author(s):  
Jorge Lorenzo Calvo ◽  
Xueyin Fei ◽  
Raúl Domínguez ◽  
Helios Pareja-Galeano

Cognitive functions are essential in any form of exercise. Recently, interest has mounted in addressing the relationship between caffeine intake and cognitive performance during sports practice. This review examines this relationship through a structured search of the databases Medline/PubMed and Web of Science for relevant articles published in English from August 1999 to March 2020. The study followed PRISMA guidelines. Inclusion criteria were defined according to the PICOS model. The identified records reported on randomized cross-over studies in which caffeine intake (as drinks, capsules, energy bars, or gum) was compared to an identical placebo situation. There were no filters on participants’ training level, gender, or age. For the systematic review, 13 studies examining the impacts of caffeine on objective measures of cognitive performance or self-reported cognitive performance were selected. Five of these studies were also subjected to meta-analysis. After pooling data in the meta-analysis, the significant impacts of caffeine only emerged on attention, accuracy, and speed. The results of the 13 studies, nevertheless, suggest that the intake of a low/moderate dose of caffeine before and/or during exercise can improve self-reported energy, mood, and cognitive functions, such as attention; it may also improve simple reaction time, choice reaction time, memory, or fatigue, however, this may depend on the research protocols.


2008 ◽  
Vol 38 (8) ◽  
pp. 1141-1146 ◽  
Author(s):  
P. Whitty ◽  
M. Clarke ◽  
O. McTigue ◽  
S. Browne ◽  
M. Kamali ◽  
...  

BackgroundThe outcome of schizophrenia appears to be more favourable than once thought. However, methodological issues, including the reliance on diagnosis at first presentation have limited the validity of outcome studies to date.MethodWe conducted a first-episode follow-up study of 97 patients with DSM-IV schizophrenia over the first 4 years of illness. First presentation and follow-up assessments were compared using paired t tests and a forced-entry regression analysis was used to determine prognostic variables.ResultsThere were significant improvements in positive and negative symptoms and global assessment of functioning between first presentation and follow-up. At first presentation, fewer negative symptoms (t=−3.40, p<0.01), more years spent in education (t=3.25, p<0.01), and a shorter duration of untreated psychosis (DUP) (t=−2.77, p<0.01) significantly predicted a better outcome at follow-up.ConclusionsThe outcome of schizophrenia may not be as pessimistic as once thought and most patients did not display a downward deteriorating course of illness. This study supports the relationship between DUP and outcome beyond the early stages of illness.


1996 ◽  
Vol 168 (6) ◽  
pp. 702-708 ◽  
Author(s):  
Owen Yuen ◽  
Michael P. Caligiuri ◽  
Richard Williams ◽  
Ruth A. Dickson

BackgroundControversy surrounds the relationship between tardive dyskinesia (TD) and symptoms of schizophrenia. While some studies reported that negative symptoms of schizophrenia may be a risk factor for TD, others reported a relationship between TD and positive symptoms.MethodEighty-four patients were studied, of whom 47 met criteria for TD. Clinical and instrumental procedures were used to increase the sensitivity of our assessments of the presence and severity of TD. Stepwise logistic and linear regression procedures were used to identify demographic variables, psychopathology, and motor parameters associated with the presence and severity of TD.ResultsA 3-factor model consisting of age, clinical tremor, and negative symptoms explained 25% of the variance in clinical TD severity. A 6-factor model consisting of female gender, instrumental and clinical measures of parkinsonism, positive, and negative symptoms explained 49% of the variance in severity of instrumentally derived dyskinesia.ConclusionsThese results suggest that the presence of TD may be associated with positive symptoms; that the severity of TD may be related to negative symptoms; and that the relationship between negative symptoms and TD severity may be influenced by the presence of parkinsonism.


2018 ◽  
Vol 137 (5) ◽  
pp. 380-390 ◽  
Author(s):  
C. R. Krynicki ◽  
R. Upthegrove ◽  
J. F. W. Deakin ◽  
T. R. E. Barnes

2008 ◽  
Vol 193 (3) ◽  
pp. 203-209 ◽  
Author(s):  
Thomas R. E. Barnes ◽  
Verity C. Leeson ◽  
Stanley H. Mutsatsa ◽  
Hilary C. Watt ◽  
Sam B. Hutton ◽  
...  

BackgroundIn first-episode schizophrenia, longer duration of untreated psychosis (DUP) predicts poorer outcomes.AimsTo address whether the relationship between DUP and outcome is a direct causal one or the result of association between symptoms and/or cognitive functioning and social functioning at the same time point.MethodSymptoms, social function and cognitive function were assessed in 98 patients with first-episode schizphrenia at presentation and 1 year later.ResultsThere was no significant clinical difference between participants with short and long DUP at presentation. Linear regression analyses revealed that longer DUP significantly predicted more severe positive and negative symptoms and poorer social function at 1 year, independent of scores at presentation. Path analyses revealed independent direct relationships between DUP and social function, core negative symptoms and positive symptoms. There was no significant association between DUP and cognition.ConclusionsLonger DUP predicts poor social function independently of symptoms. The findings underline the importance of taking account of the phenomenological overlap between measures of negative symptoms and social function when investigating the effects of DUP.


2019 ◽  
Vol 7 (23) ◽  
pp. 4053-4058
Author(s):  
Nurul Utami ◽  
Elmeida Effendy ◽  
Mustafa Amin

BACKGROUND: BDNF implies to the development of abnormal nerves and neurotransmission that occurred during the changes of cognitive functions. However, in determining initial diagnosis of schizophrenia, measurements focus on the presences of positive and negative symptoms, and general psychopathological features without concerning the BDNF serum, which involves in central nervous system as the main symptom of schizophrenia. AIM: To determine the relation of BDNF serum level to cognitive functions of schizophrenia patients based on sub-domain of Montreal Cognitive Assessment Indonesia Version (MoCA-Ina) METHODS: This study was carried out based on observational analysis with cross-sectional design study. The samples were collected by non-probability sampling and consecutive sampling by recruiting 65 of male schizophrenia patients at Prof. Dr. M. Ildrem Mental Hospital, Medan, North Sumatera, Indonesia. BDNF serum levels were analysed throughout quantitative sandwich enzyme immunoassay method, while the cognitive functions were conducted by performing the MoCA-Ina, which concern to attentions and concentrations, executive function, memory, languages, visuoconstructional abilities, numerical calculation, and orientation. RESULTS: The serum level of BDNF was accounted averagely for 27161.26, with 5350.37 of standard deviation. There was positive correlation with medium strength (r = 0.4 - < 0.6) in visuospatial function, attention (r = 0.437), and memory (r = 0.413). CONCLUSION: Relation between BDNF serum level and cognitive function occurred in visuospatial, attention and memory domains based on MoCA-Ina assessment.


2007 ◽  
Vol 24 (4) ◽  
pp. 145-148 ◽  
Author(s):  
Richard Lawoyin ◽  
Keith Gaynor ◽  
Barbara Dooley ◽  
Elizabeth Lawlor ◽  
Mary Clarke ◽  
...  

AbstractObjectives: To examine the relationship between cognitive deficits, the duration of untreated psychosis (DUP) and positive and negative symptoms in a first episode psychosis sample.Method: We assessed a consecutive sample of first episode psychosis participants from a catchment area service with a comprehensive neuropsychology battery, a family and service-user based measure of DUP and measures of symptomatology.Results: Using correlations and stepwise linear regressions, we found strong relationships between measures of DUP and positive symptomatology. We found that positive and negative symptoms were associated with different time periods within DUP. However, we did not find evidence of a relationship between DUP and cognitive factors.Conclusions: There was no evidence of a relationship between DUP and cognitive deterioration. However, there does appear to be evidence of a relationship between positive symptoms and aspects of DUP. These results highlight the importance of the heterogeneity of DUP and the potential to reduce positive symptoms through early intervention.


2019 ◽  
Author(s):  
Tesfa Dejenie Habtewold ◽  
Lyan H. Rodijk ◽  
Edith J. Liemburg ◽  
Grigory Sidorenkov ◽  
H. Marike Boezen ◽  
...  

AbstractIntroductionTo tackle the phenotypic heterogeneity of schizophrenia, data-driven methods are often applied to identify subtypes of its (sub)clinical symptoms though there is no systematic review.AimsTo summarize the evidence from cluster- and trajectory-based studies of positive, negative and cognitive symptoms in patients with schizophrenia spectrum disorders, their siblings and healthy people. Additionally, we aimed to highlight knowledge gaps and point out future directions to optimize the translatability of cluster- and trajectory-based studies.MethodsA systematic review was performed through searching PsycINFO, PubMed, PsycTESTS, PsycARTICLES, SCOPUS, EMBASE, and Web of Science electronic databases. Both cross-sectional and longitudinal studies published from 2008 to 2019, which reported at least two statistically derived clusters or trajectories were included. Two reviewers independently screened and extracted the data.ResultsOf 2,285 studies retrieved, 50 studies (17 longitudinal and 33 cross-sectional) conducted in 30 countries were selected for review. Longitudinal studies discovered two to five trajectories of positive and negative symptoms in patient, and four to five trajectories of cognitive deficits in patient and sibling. In cross-sectional studies, three clusters of positive and negative symptoms in patient, four clusters of positive and negative schizotypy in sibling, and three to five clusters of cognitive deficits in patient and sibling were identified. These studies also reported multidimensional predictors of clusters and trajectories.ConclusionsOur findings indicate that (sub)clinical symptoms of schizophrenia are more heterogeneous than currently recognized. Identified clusters and trajectories can be used as a basis for personalized psychiatry.


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