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Health Technology Assessment... Nov 2018Although many treatments exist for phantom limb pain (PLP), the evidence supporting them is limited and there are no guidelines for PLP management. Brain and spinal cord...
BACKGROUND
Although many treatments exist for phantom limb pain (PLP), the evidence supporting them is limited and there are no guidelines for PLP management. Brain and spinal cord neurostimulation therapies are targeted at patients with chronic PLP but have yet to be systematically reviewed.
OBJECTIVE
To determine which types of brain and spinal stimulation therapy appear to be the best for treating chronic PLP.
DESIGN
Systematic reviews of effectiveness and epidemiology studies, and a survey of NHS practice.
POPULATION
All patients with PLP.
INTERVENTIONS
Invasive interventions - deep brain stimulation (DBS), motor cortex stimulation (MCS), spinal cord stimulation (SCS) and dorsal root ganglion (DRG) stimulation. Non-invasive interventions - repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS).
MAIN OUTCOME MEASURES
Phantom limb pain and quality of life.
DATA SOURCES
Twelve databases (including MEDLINE and EMBASE) and clinical trial registries were searched in May 2017, with no date limits applied.
REVIEW METHODS
Two reviewers screened titles and abstracts and full texts. Data extraction and quality assessments were undertaken by one reviewer and checked by another. A questionnaire was distributed to clinicians via established e-mail lists of two relevant clinical societies. All results were presented narratively with accompanying tables.
RESULTS
Seven randomised controlled trials (RCTs), 30 non-comparative group studies, 18 case reports and 21 epidemiology studies were included. Results from a good-quality RCT suggested short-term benefits of rTMS in reducing PLP, but not in reducing anxiety or depression. Small randomised trials of tDCS suggested the possibility of modest, short-term reductions in PLP. No RCTs of invasive therapies were identified. Results from small, non-comparative group studies suggested that, although many patients benefited from short-term pain reduction, far fewer maintained their benefits. Most studies had important methodological or reporting limitations and few studies reported quality-of-life data. The evidence on prognostic factors for the development of chronic PLP from the longitudinal studies also had important limitations. The results from these studies suggested that pre-amputation pain and early PLP intensity are good predictors of chronic PLP. Results from the cross-sectional studies suggested that the proportion of patients with severe chronic PLP is between around 30% and 40% of the chronic PLP population, and that around one-quarter of chronic PLP patients find their PLP to be either moderately or severely limiting or bothersome. There were 37 responses to the questionnaire distributed to clinicians. SCS and DRG stimulation are frequently used in the NHS but the prevalence of use of DBS and MCS was low. Most responders considered SCS and DRG stimulation to be at least sometimes effective. Neurosurgeons had mixed views on DBS, but most considered MCS to rarely be effective. Most clinicians thought that a randomised trial design could be successfully used to study neurostimulation therapies.
LIMITATION
There was a lack of robust research studies.
CONCLUSIONS
Currently available studies of the efficacy, effectiveness and safety of neurostimulation treatments do not provide robust, reliable results. Therefore, it is uncertain which treatments are best for chronic PLP.
FUTURE WORK
Randomised crossover trials, randomised N-of-1 trials and prospective registry trials are viable study designs for future research.
STUDY REGISTRATION
The study is registered as PROSPERO CRD42017065387.
FUNDING
The National Institute for Health Research Health Technology Assessment programme.
Topics: Clinical Trials as Topic; Deep Brain Stimulation; Electric Stimulation Therapy; Humans; Pain Management; Phantom Limb; Quality of Life; Spinal Cord Stimulation; Transcranial Direct Current Stimulation
PubMed: 30407905
DOI: 10.3310/hta22620 -
PloS One 2016Faces play a key role in signaling social cues such as signals of trustworthiness. Although several studies identify the amygdala as a core brain region in social... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Faces play a key role in signaling social cues such as signals of trustworthiness. Although several studies identify the amygdala as a core brain region in social cognition, quantitative approaches evaluating its role are scarce.
OBJECTIVES
This review aimed to assess the role of the amygdala in the processing of facial trustworthiness, by analyzing its amplitude BOLD response polarity to untrustworthy versus trustworthy facial signals under fMRI tasks through a Meta-analysis of effect sizes (MA). Activation Likelihood Estimation (ALE) analyses were also conducted.
DATA SOURCES
Articles were retrieved from MEDLINE, ScienceDirect and Web-of-Science in January 2016. Following the PRISMA statement guidelines, a systematic review of original research articles in English language using the search string "(face OR facial) AND (trustworthiness OR trustworthy OR untrustworthy OR trustee) AND fMRI" was conducted.
STUDY SELECTION AND DATA EXTRACTION
The MA concerned amygdala responses to facial trustworthiness for the contrast Untrustworthy vs. trustworthy faces, and included whole-brain and ROI studies. To prevent potential bias, results were considered even when at the single study level they did not survive correction for multiple comparisons or provided non-significant results. ALE considered whole-brain studies, using the same methodology to prevent bias. A summary of the methodological options (design and analysis) described in the articles was finally used to get further insight into the characteristics of the studies and to perform a subgroup analysis. Data were extracted by two authors and checked independently.
DATA SYNTHESIS
Twenty fMRI studies were considered for systematic review. An MA of effect sizes with 11 articles (12 studies) showed high heterogeneity between studies [Q(11) = 265.68, p < .0001; I2 = 95.86%, 94.20% to 97.05%, with 95% confidence interval, CI]. Random effects analysis [RE(183) = 0.851, .422 to .969, 95% CI] supported the evidence that the (right) amygdala responds preferentially to untrustworthy faces. Moreover, two ALE analyses performed with 6 articles (7 studies) identified the amygdala, insula and medial dorsal nuclei of thalamus as structures with negative correlation with trustworthiness. Six articles/studies showed that posterior cingulate and medial frontal gyrus present positive correlations with increasing facial trustworthiness levels. Significant effects considering subgroup analysis based on methodological criteria were found for experiments using spatial smoothing, categorization of trustworthiness in 2 or 3 categories and paradigms which involve both explicit and implicit tasks.
LIMITATIONS
Significant heterogeneity between studies was found in MA, which might have arisen from inclusion of studies with smaller sample sizes and differences in methodological options. Studies using ROI analysis / small volume correction methods were more often devoted specifically to the amygdala region, with some results reporting uncorrected p-values based on mainly clinical a priori evidence of amygdala involvement in these processes. Nevertheless, we did not find significant evidence for publication bias.
CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS
Our results support the role of amygdala in facial trustworthiness judgment, emphasizing its predominant role during processing of negative social signals in (untrustworthy) faces. This systematic review suggests that little consistency exists among studies' methodology, and that larger sample sizes should be preferred.
Topics: Amygdala; Brain; Databases, Factual; Face; Humans; Likelihood Functions; Magnetic Resonance Imaging; Pattern Recognition, Visual
PubMed: 27898705
DOI: 10.1371/journal.pone.0167276 -
Journal of Conservative Dentistry and... Apr 2024The aim was to determine whether premixed calcium silicate-based root canal sealers have better biological properties than AH Plus. (Review)
Review
Premixed calcium silicate-based root canal sealers have better biological properties than AH Plus: A systematic review and meta-analysis of in vivo animal studies and laboratory studies.
OBJECTIVES
The aim was to determine whether premixed calcium silicate-based root canal sealers have better biological properties than AH Plus.
MATERIALS AND METHODS
Searches of studies published up to January 2023 were performed in the PubMed/MEDLINE and EMBASE and via other methods (databases of the International Endodontic Journal, Journal of Endodontics, and gray literature). The inclusion criteria were animal and studies that analyzed the response in the dorsal subcutaneous tissue of rats, cell viability, and genotoxicity. Systematic Review Centre for Laboratory Animal Experimentation Risk of Bias (RoB) tool for studies and modified CONSORT checklist for were appraised. Meta-analysis was performed using the Stata.
RESULTS
Fifty-two studies were included. In the RoB, studies fulfilled 20%-50% of the items and 60%-100%. The studies included in the meta-analysis demonstrated better histocompatibility with the premixed calcium silicate-based sealers at 30 days and greater cell viability with these sealers when used in undiluted extracts in experimental period of 72 h and in extracts with 1:2 and 1:4 dilution in 24 and 72 h. In contrast, no difference between materials was found concerning genotoxicity.
CONCLUSION
Premixed calcium silicate-based root canal sealers have better histocompatibility and are less cytotoxic than the epoxy resin-based sealer AH Plus, demonstrating favorable biological behavior.
PubMed: 38779200
DOI: 10.4103/JCDE.JCDE_24_24 -
Molecular Autism Jan 2023The long-described atypicalities of memory functioning experienced by people with autism have major implications for daily living, academic learning, as well as... (Review)
Review
The long-described atypicalities of memory functioning experienced by people with autism have major implications for daily living, academic learning, as well as cognitive remediation. Though behavioral studies have identified a robust profile of memory strengths and weaknesses in autism spectrum disorder (ASD), few works have attempted to establish a synthesis concerning their neural bases. In this systematic review of functional neuroimaging studies, we highlight functional brain asymmetries in three anatomical planes during memory processing between individuals with ASD and typical development. These asymmetries consist of greater activity of the left hemisphere than the right in ASD participants, of posterior brain regions-including hippocampus-rather than anterior ones, and presumably of the ventral (occipito-temporal) streams rather than the dorsal (occipito-parietal) ones. These functional alterations may be linked to atypical memory processes in ASD, including the pre-eminence of verbal over spatial information, impaired active maintenance in working memory, and preserved relational memory despite poor context processing in episodic memory.
Topics: Humans; Autistic Disorder; Autism Spectrum Disorder; Magnetic Resonance Imaging; Brain; Functional Neuroimaging; Brain Mapping
PubMed: 36627713
DOI: 10.1186/s13229-022-00525-2 -
JAMA Facial Plastic Surgery Dec 2019While extracorporeal septoplasty (ECS) and its modifications have been previously studied, to our knowledge, no systematic review of surgical outcomes and complications... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
While extracorporeal septoplasty (ECS) and its modifications have been previously studied, to our knowledge, no systematic review of surgical outcomes and complications of this technique has been performed.
OBJECTIVE
To evaluate the evidence of surgical outcomes and complications of ECS (including modified techniques) to treat severe L-strut septal deviation defined as deviation within 1.0 cm of the caudal or dorsal septum.
DATA SOURCES
MEDLINE, Embase, CINAHL, CENTRAL, Scopus, and Web of Science databases and reference lists were searched from inception to April 2018 for clinical and observational studies. Search terms included extracorporeal, septoplasty, and septum.
STUDY SELECTION
Selection criteria were defined according to the population, intervention, comparison, and outcome framework. Relevant studies were selected by 2 independent reviewers based on abstracts and full texts.
DATA EXTRACTION AND SYNTHESIS
Data were extracted using standardized lists chosen by the authors according to Cochrane Collaboration guidelines. Data were collected and synthesized with ranges reported, as well as assessment of bias and heterogeneity when applicable. Analysis started in February 2019.
MAIN OUTCOMES AND MEASURES
Outcomes assessed included functional nasal airway improvement by objective measurements and subjective measurements (Nasal Obstruction Symptom Evaluation [NOSE] and visual analog scale scores); complications including bleeding, infection, dorsal irregularities, and other functional or cosmetic deficits; and as revision surgery rates.
RESULTS
Of 291 records initially obtained, 31 were considered relevant after review according to PRISMA guidelines. All studies except 1 randomized clinical trial (3.2%) were observational in nature, with 21 retrospective studies (67.7%) and 9 prospective studies (29.0%). Conventional ECS was performed in 16 studies (51.6%), and modified ECS was performed in 15 studies (48.4%). The sample size varied from 10 to 567, and the mean age varied from 22.5 to 46 years. Of 31 studies, 14 (45%) were of good methodology. Meta-analysis was performed on 5 studies reporting change in NOSE scores, with pooled effect of -60.0 (95% CI, -67.8 to -52.2) points, but heterogeneity was high, with I2 = 96%. When comparing complications between modified and conventional ECS, the relative risk for infections was 0.95 (95% CI, 0.34-2.7); for bleeding, 0; for nasal dorsal irregularities, 0.29 (95% CI, 0.16-0.53); for other cosmetic complications, 4.3 (95% CI, 0.87-21.1); for other functional complications, 0.47 (95% CI, 0.20-1.1); and for revision operations, 1.4 (95% CI, 0.83-2.3).
CONCLUSIONS AND RELEVANCE
Of the 31 studies included in this systematic review, less than half were of good methodology, and a significant level of heterogeneity was found regarding type of outcome measure used and reporting of complications. To improve the level of evidence, better study methodology, standardization of surgical outcomes measures, and reporting of complications are needed.
Topics: Humans; Nasal Obstruction; Nasal Septum; Nose Deformities, Acquired; Rhinoplasty
PubMed: 31621791
DOI: 10.1001/jamafacial.2019.1020 -
The Cochrane Database of Systematic... Dec 2021Implanted spinal neuromodulation (SNMD) techniques are used in the treatment of refractory chronic pain. They involve the implantation of electrodes around the spinal... (Review)
Review
BACKGROUND
Implanted spinal neuromodulation (SNMD) techniques are used in the treatment of refractory chronic pain. They involve the implantation of electrodes around the spinal cord (spinal cord stimulation (SCS)) or dorsal root ganglion (dorsal root ganglion stimulation (DRGS)), and a pulse generator unit under the skin. Electrical stimulation is then used with the aim of reducing pain intensity.
OBJECTIVES
To evaluate the efficacy, effectiveness, adverse events, and cost-effectiveness of implanted spinal neuromodulation interventions for people with chronic pain.
SEARCH METHODS
We searched CENTRAL, MEDLINE Ovid, Embase Ovid, Web of Science (ISI), Health Technology Assessments, ClinicalTrials.gov and World Health Organization International Clinical Trials Registry from inception to September 2021 without language restrictions, searched the reference lists of included studies and contacted experts in the field.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) comparing SNMD interventions with placebo (sham) stimulation, no treatment or usual care; or comparing SNMD interventions + another treatment versus that treatment alone. We included participants ≥ 18 years old with non-cancer and non-ischaemic pain of longer than three months duration. Primary outcomes were pain intensity and adverse events. Secondary outcomes were disability, analgesic medication use, health-related quality of life (HRQoL) and health economic outcomes.
DATA COLLECTION AND ANALYSIS
Two review authors independently screened database searches to determine inclusion, extracted data and evaluated risk of bias for prespecified results using the Risk of Bias 2.0 tool. Outcomes were evaluated at short- (≤ one month), medium- four to eight months) and long-term (≥12 months). Where possible we conducted meta-analyses. We used the GRADE system to assess the certainty of evidence.
MAIN RESULTS
We included 15 unique published studies that randomised 908 participants, and 20 unique ongoing studies. All studies evaluated SCS. We found no eligible published studies of DRGS and no studies comparing SCS with no treatment or usual care. We rated all results evaluated as being at high risk of bias overall. For all comparisons and outcomes where we found evidence, we graded the certainty of the evidence as low or very low, downgraded due to limitations of studies, imprecision and in some cases, inconsistency. Active stimulation versus placebo SCS versus placebo (sham) Results were only available at short-term follow-up for this comparison. Pain intensity Six studies (N = 164) demonstrated a small effect in favour of SCS at short-term follow-up (0 to 100 scale, higher scores = worse pain, mean difference (MD) -8.73, 95% confidence interval (CI) -15.67 to -1.78, very low certainty). The point estimate falls below our predetermined threshold for a clinically important effect (≥10 points). No studies reported the proportion of participants experiencing 30% or 50% pain relief for this comparison. Adverse events (AEs) The quality and inconsistency of adverse event reporting in these studies precluded formal analysis. Active stimulation + other intervention versus other intervention alone SCS + other intervention versus other intervention alone (open-label studies) Pain intensity Mean difference Three studies (N = 303) demonstrated a potentially clinically important mean difference in favour of SCS of -37.41 at short term (95% CI -46.39 to -28.42, very low certainty), and medium-term follow-up (5 studies, 635 participants, MD -31.22 95% CI -47.34 to -15.10 low-certainty), and no clear evidence for an effect of SCS at long-term follow-up (1 study, 44 participants, MD -7 (95% CI -24.76 to 10.76, very low-certainty). Proportion of participants reporting ≥50% pain relief We found an effect in favour of SCS at short-term (2 studies, N = 249, RR 15.90, 95% CI 6.70 to 37.74, I 0% ; risk difference (RD) 0.65 (95% CI 0.57 to 0.74, very low certainty), medium term (5 studies, N = 597, RR 7.08, 95 %CI 3.40 to 14.71, I = 43%; RD 0.43, 95% CI 0.14 to 0.73, low-certainty evidence), and long term (1 study, N = 87, RR 15.15, 95% CI 2.11 to 108.91 ; RD 0.35, 95% CI 0.2 to 0.49, very low certainty) follow-up. Adverse events (AEs) Device related No studies specifically reported device-related adverse events at short-term follow-up. At medium-term follow-up, the incidence of lead failure/displacement (3 studies N = 330) ranged from 0.9 to 14% (RD 0.04, 95% CI -0.04 to 0.11, I 64%, very low certainty). The incidence of infection (4 studies, N = 548) ranged from 3 to 7% (RD 0.04, 95%CI 0.01, 0.07, I 0%, very low certainty). The incidence of reoperation/reimplantation (4 studies, N =5 48) ranged from 2% to 31% (RD 0.11, 95% CI 0.02 to 0.21, I 86%, very low certainty). One study (N = 44) reported a 55% incidence of lead failure/displacement (RD 0.55, 95% CI 0.35, 0 to 75, very low certainty), and a 94% incidence of reoperation/reimplantation (RD 0.94, 95% CI 0.80 to 1.07, very low certainty) at five-year follow-up. No studies provided data on infection rates at long-term follow-up. We found reports of some serious adverse events as a result of the intervention. These included autonomic neuropathy, prolonged hospitalisation, prolonged monoparesis, pulmonary oedema, wound infection, device extrusion and one death resulting from subdural haematoma. Other No studies reported the incidence of other adverse events at short-term follow-up. We found no clear evidence of a difference in otherAEs at medium-term (2 studies, N = 278, RD -0.05, 95% CI -0.16 to 0.06, I 0%) or long term (1 study, N = 100, RD -0.17, 95% CI -0.37 to 0.02) follow-up. Very limited evidence suggested that SCS increases healthcare costs. It was not clear whether SCS was cost-effective.
AUTHORS' CONCLUSIONS
We found very low-certainty evidence that SCS may not provide clinically important benefits on pain intensity compared to placebo stimulation. We found low- to very low-certainty evidence that SNMD interventions may provide clinically important benefits for pain intensity when added to conventional medical management or physical therapy. SCS is associated with complications including infection, electrode lead failure/migration and a need for reoperation/re-implantation. The level of certainty regarding the size of those risks is very low. SNMD may lead to serious adverse events, including death. We found no evidence to support or refute the use of DRGS for chronic pain.
Topics: Adolescent; Adult; Bias; Chronic Pain; Humans; Pain Measurement; Quality of Life; Wound Infection
PubMed: 34854473
DOI: 10.1002/14651858.CD013756.pub2 -
The Journal of Foot and Ankle Surgery :... 2022Recognition of metatarsophalangeal joint plantar plate injuries has improved over time as the condition has become more widely understood and identified. With the... (Meta-Analysis)
Meta-Analysis
Recognition of metatarsophalangeal joint plantar plate injuries has improved over time as the condition has become more widely understood and identified. With the diagnosis of a plantar plate injury as a subset of metatarsalgia becoming more common place, there are multiple surgical options that have been utilized to address the condition. Direct repair of the plantar plate has emerged as the treatment of choice for foot surgeons with a tendency to favor a direct dorsal approach for the repair. We performed a systematic review and meta-analysis using preferred reporting items for systematic reviews and meta-analysis guidelines, to determine the magnitude of change that can be expected in visual analog scale pain and American Orthopedic Foot and Ankle Society scores postoperatively. A total of 12 studies involving 537 plantar plate tears were included who underwent direct repair of the plantar plate through either a dorsal (10 articles) or plantar approach (2 articles). Summary estimates were calculated which revealed improvement in visual analog scale pain (pooled mean change of -5.01 [95%CI -5.36, -4.66] pre-to postoperative) and improvement in American Orthopedic Foot and Ankle Society scores (pooled postoperative mean improvement 40.44 [95%CI 37.90, 42.97]) of patients within the included studies. Random effects models were used for summary estimates. I statistic was used to assess for heterogeneity. We concluded there is a predictable level of improvement in pain and function in patients undergoing a direct dorsal approach plantar plate repair with follow-up out to 2 years.
Topics: Humans; Joint Instability; Metatarsalgia; Metatarsophalangeal Joint; Osteotomy; Plantar Plate
PubMed: 35283034
DOI: 10.1053/j.jfas.2022.02.002 -
Minimally Invasive Surgery 2021Spinal cord stimulation (SCS) is a minimally invasive technique mainly used to treat neuropathic pain associated with failed back surgery syndrome. However, this therapy... (Review)
Review
OBJECTIVE
Spinal cord stimulation (SCS) is a minimally invasive technique mainly used to treat neuropathic pain associated with failed back surgery syndrome. However, this therapy has been utilized to treat other chronic painful conditions, such as pain associated with multiple sclerosis (MS). Nonetheless, the efficacy of SCS in MS patients has not been fully established. In fact, in most of SCS series, MS patients represent only a subset of a bigger cohort which comprises different causes of pain, motor disorder, and other functional limitations. The aim of our study was to systematically review the literature to evaluate the effectiveness of SCS in MS patients.
METHODS
A literature search was performed through different databases (PubMed, Scopus, and Embase) using the following terms: "multiple sclerosis," "spinal cord stimulation," and "dorsal column stimulation," according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines.
RESULTS
A total of 452 articles were reviewed, and 7 studies were included in the present analysis. 373 MS patients were submitted to a stimulation trial, and 82 MS patients underwent a de novo implantation. 285/373 (76.4%) of cases submitted to the SCS trial were enrolled for permanent stimulation. We found a long-lasting improvement in 193/346 (55.8%) MS patients with motor disorders, in 90/134 (67.13%) MS patients with urinary dysfunction, and in 28/34 (82.35%) MS patients with neuropathic pain. The efficacy of SCS was higher for urinary dysfunction ( = 0.0144) and neuropathic pain ( = 0.0030) compared with motor disorders.
CONCLUSIONS
Our systematic review evidences that SCS is effective in MS patients. Urinary dysfunction and pain symptoms seem to be most responsive to SCS. Further studies are needed to improve the patient selection and clarify the best timing to perform SCS in these patients.
PubMed: 33986958
DOI: 10.1155/2021/9969010 -
European Spine Journal : Official... Jan 2021Dorsal screw-rod instrumentations are used for a variety of spinal disorders. Cross-links (CL) can be added to such constructs, however, no clear recommendations exist.... (Review)
Review
PURPOSE
Dorsal screw-rod instrumentations are used for a variety of spinal disorders. Cross-links (CL) can be added to such constructs, however, no clear recommendations exist. This study aims to provide an overview of the available evidence on the effectiveness of CL, potentially allowing to formulate recommendations on their use.
METHODS
A systematic literature review was performed on PubMed and 37 original articles were included and grouped into mechanical, biomechanical, finite element and clinical studies. The change in range of motion (ROM) was analyzed in mechanical and biomechanical studies, ROM, stiffness and stress distribution were evaluated in finite element studies and clinical outcome parameters were analyzed in clinical studies.
RESULTS
A relative consistent reduction in ROM in axial rotation with CL-augmentation was reported, while minor and less consistent effects were observed in flexion-extension and lateral bending. The use of CLs was clinical beneficial in C1/2 fusion, while the limited clinical studies on other anatomic regions show no significant benefit for CL-augmentation.
CONCLUSION
While CL provides some additional axial rotation stability in most situations, lateral bending and flexion-extension are less affected. Based on clinical data, CL-augmentation can only be recommended for C1/2 instrumentations, while for other cases, further clinical studies are needed to allow for evidence-based recommendations.
Topics: Biomechanical Phenomena; Cadaver; Humans; Lumbar Vertebrae; Pedicle Screws; Range of Motion, Articular; Spinal Fusion
PubMed: 33009949
DOI: 10.1007/s00586-020-06597-z -
Frontiers in Neurology 2019Schizophrenia is characterized by self-disturbances, including impaired self-evaluation abilities and source monitoring. The cortical midline structures (e.g., medial...
Schizophrenia is characterized by self-disturbances, including impaired self-evaluation abilities and source monitoring. The cortical midline structures (e.g., medial prefrontal cortex, anterior and posterior cingulate cortex, and precuneus) and the temporoparietal junction are known to play a key role in self-related processing. In theory, self-disturbances in schizophrenia may arise from impaired activity in these regions. We performed a functional neuroimaging meta-analysis to verify this hypothesis. A literature search was performed with PubMed and Google Scholar to identify functional neuroimaging studies examining the neural correlates of self-processing in schizophrenia, using self-other or source monitoring paradigms. Fourteen studies were retrieved, involving 245 patients and 201 controls. Using peak coordinates to recreate an effect-size map of contrast results, a standard random-effects variance weighted meta-analysis for each voxel was performed with the software. During self-processing, decreased activations were observed in schizophrenia patients relative to controls in the bilateral thalamus and the left dorsal anterior cingulate cortex (dACC) and dorso-medial prefrontal cortex. Importantly, results were homogeneous across studies, and no publication bias was observed. Sensitivity analyses revealed that results were replicable in 93-100% of studies. The current results partially support the hypothesized impaired activity of cortical midline brain regions in schizophrenia during self-processing. Decreased activations were observed in the dACC and dorsomedial prefrontal cortex, which are involved in cognitive control and/or salience attribution, as well as decision-making, respectively. These alterations may compromise patients' ability to direct their attention toward themselves and/or others and to make the decision whether a certain trait applies to one's self or to someone else. In addition, decreased activations were observed in the thalamus, which is not a core region of the default-mode network, and is involved in information integration. These thalamic alterations may compromise self-coherence in schizophrenia.
PubMed: 31572296
DOI: 10.3389/fneur.2019.00990