Altered brain development is evident in children born very preterm (24-32 weeks gestational age), including reduction in gray and white matter volumes, and thinner cortex, from infancy to adolescence ...compared to term-born peers. However, many questions remain regarding the etiology. Infants born very preterm are exposed to repeated procedural pain-related stress during a period of very rapid brain development. In this vulnerable population, we have previously found that neonatal pain-related stress is associated with atypical brain development from birth to term-equivalent age. Our present aim was to evaluate whether neonatal pain-related stress (adjusted for clinical confounders of prematurity) is associated with altered cortical thickness in very preterm children at school age.
42 right-handed children born very preterm (24-32 weeks gestational age) followed longitudinally from birth underwent 3-D T1 MRI neuroimaging at mean age 7.9 yrs. Children with severe brain injury and major motor/sensory/cognitive impairment were excluded. Regional cortical thickness was calculated using custom developed software utilizing FreeSurfer segmentation data. The association between neonatal pain-related stress (defined as the number of skin-breaking procedures) accounting for clinical confounders (gestational age, illness severity, infection, mechanical ventilation, surgeries, and morphine exposure), was examined in relation to cortical thickness using constrained principal component analysis followed by generalized linear modeling.
After correcting for multiple comparisons and adjusting for neonatal clinical factors, greater neonatal pain-related stress was associated with significantly thinner cortex in 21/66 cerebral regions (p-values ranged from 0.00001 to 0.014), predominately in the frontal and parietal lobes.
In very preterm children without major sensory, motor or cognitive impairments, neonatal pain-related stress appears to be associated with thinner cortex in multiple regions at school age, independent of other neonatal risk factors.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A parameterization of mineral dust within the Hadley Centre atmospheric general circulation model (AGCM) is described, modeled dust distributions are compared with observations, and estimates of the ...radiative forcing due to the inclusion of dust in the model are obtained. The parameterization uses six particle size divisions in the range 0.3–30 μm radius, and all calculations are performed on each division independently, using the GCM's prognostic variables. The dust production scheme works within the GCM and includes dependencies on particle size distribution, soil moisture, vegetation, and friction velocity. Dust transport is carried out by the GCM's tracer advection scheme and includes vertical motion due to convection, gravitational settling, and turbulent mixing in the boundary layer. Wet and dry deposition processes are included within the GCM's precipitation schemes. Representative dust radiative parameters are incorporated into the GCM's two stream radiation code. Modeled monthly average near‐surface dust concentrations are compared with observations: good agreement is seen in most locations, though the dust scheme tends to produce too little dust from China and too much from Australia in the southern spring. Global annual mean direct forcing due to the inclusion of dust in the GCM is +0.07 W m−2 at the top of the atmosphere (TOA) and −0.82 W m−2 at the surface. The geographical distributions of annual mean forcings are very inhomogeneous, with peak values exceeding the global means by a factor of approximately 2 orders of magnitude.
Prochlorococcus is the numerically dominant phytoplankter in the oligotrophic oceans, accounting for up to half of the photosynthetic biomass and production in some regions. Here, we describe how the ...abundance of six known ecotypes, which have small subunit ribosomal RNA sequences that differ by less than 3%, changed along local and basin-wide environmental gradients in the Atlantic Ocean. Temperature was significantly correlated with shifts in ecotype abundance, and laboratory experiments confirmed different temperature optima and tolerance ranges for cultured strains. Light, nutrients, and competitor abundances also appeared to play a role in shaping different distributions.
While the majority of cognitive studies on auditory hallucinations (AHs) have been conducted in schizophrenia (SZ), an increasing number of researchers are turning their attention to different ...clinical and nonclinical populations, often using SZ findings as a model for research. Recent advances derived from SZ studies can therefore be utilized to make substantial progress on AH research in other groups. The objectives of this article were to (1) present an up-to-date review regarding the cognitive mechanisms of AHs in SZ, (2) review findings from cognitive research conducted in other clinical and nonclinical groups, and (3) integrate these recent findings into a cohesive framework. First, SZ studies show that the cognitive underpinnings of AHs include self-source-monitoring deficits and executive and inhibitory control dysfunctions as well as distortions in top-down mechanisms, perceptual and linguistic processes, and emotional factors. Second, consistent with SZ studies, findings in other population groups point to the role of top-down processing, abnormalities in executive inhibition, and negative emotions. Finally, we put forward an integrated model of AHs that incorporates the above findings. We suggest that AHs arise from an interaction between abnormal neural activation patterns that produce salient auditory signals and top-down mechanisms that include signal detection errors, executive and inhibition deficits, a tapestry of expectations and memories, and state characteristics that influence how these experiences are interpreted. Emotional factors play a particular prominent role at all levels of this hierarchy. Our model is distinctively powerful in explaining a range of phenomenological characteristics of AH across a spectrum of disorders.
Auditory verbal hallucinations (AVH) occur in psychotic disorders, but also as a symptom of other conditions and even in healthy people. Several current theories on the origin of AVH converge, with ...neuroimaging studies suggesting that the language, auditory and memory/limbic networks are of particular relevance. However, reconciliation of these theories with experimental evidence is missing. We review 50 studies investigating functional (EEG and fMRI) and anatomic (diffusion tensor imaging) connectivity in these networks, and explore the evidence supporting abnormal connectivity in these networks associated with AVH. We distinguish between functional connectivity during an actual hallucination experience (symptom capture) and functional connectivity during either the resting state or a task comparing individuals who hallucinate with those who do not (symptom association studies). Symptom capture studies clearly reveal a pattern of increased coupling among the auditory, language and striatal regions. Anatomical and symptom association functional studies suggest that the interhemispheric connectivity between posterior auditory regions may depend on the phase of illness, with increases in non-psychotic individuals and first episode patients and decreases in chronic patients. Leading hypotheses involving concepts as unstable memories, source monitoring, top-down attention, and hybrid models of hallucinations are supported in part by the published connectivity data, although several caveats and inconsistencies remain. Specifically, possible changes in fronto-temporal connectivity are still under debate. Precise hypotheses concerning the directionality of connections deduced from current theoretical approaches should be tested using experimental approaches that allow for discrimination of competing hypotheses.
The natural environment is a major source of atmospheric aerosols, including dust, secondary organic material from terrestrial biogenic emissions, carbonaceous particles from wildfires, and sulphate ...from marine phytoplankton dimethyl sulphide emissions. These aerosols also have a significant effect on many components of the Earth system such as the atmospheric radiative balance and photosynthetically available radiation entering the biosphere, the supply of nutrients to the ocean, and the albedo of snow and ice. The physical and biological systems that produce these aerosols can be highly susceptible to modification due to climate change so there is the potential for important climate feedbacks. We review the impact of these natural systems on atmospheric aerosol based on observations and models, including the potential for long term changes in emissions and the feedbacks on climate. The number of drivers of change is very large and the various systems are strongly coupled. There have therefore been very few studies that integrate the various effects to estimate climate feedback factors. Nevertheless, available observations and model studies suggest that the regional radiative perturbations are potentially several Watts per square metre due to changes in these natural aerosol emissions in a future climate. Taking into account only the direct radiative effect of changes in the atmospheric burden of natural aerosols, and neglecting potentially large effects on other parts of the Earth system, a global mean radiative perturbation approaching 1 W m−2 is possible by the end of the century. The level of scientific understanding of the climate drivers, interactions and impacts is very low.
The present article provides a narrative review of empirical studies on metacognitive training in psychosis (MCT). MCT represents an amalgam of cognitive-behavioral therapy (CBT), cognitive ...remediation (CRT) and psychoeducation. The intervention is available in either a group (MCT) or an individualized (MCT+) format. By sowing the seeds of doubt in a playful and entertaining fashion, the program targets positive symptoms, particularly delusions. It aims to raise patients’ awareness for common cognitive traps or biases (e.g., jumping to conclusions, overconfidence in errors, bias against disconfirmatory evidence) that are implicated in the formation and maintenance of psychosis. The majority of studies confirm that MCT meets its core aim, the reduction of delusions. Problems (e.g., potential allegiance effects) and knowledge gaps (i.e., outcome predictors) are highlighted. The preliminary data suggest that the individual MCT format is especially effective in addressing symptoms, cognitive biases and insight. We conclude that MCT appears to be a worthwhile complement to pharmacotherapy.
•Recovery under antipsychotics is incomplete.•Dissemination of psychotherapy in psychosis is still poor.•Metacognitive training (MCT) is available for free in 31 languages.•MCT, particularly its individualized version, improves positive symptoms.
Although antipsychotic medication still represents the treatment of choice for schizophrenia, its objective impact on symptoms is only in the medium-effect size range and at least 50% of patients ...discontinue medication in the course of treatment. Hence, clinical researchers are intensively looking for complementary therapeutic options. Metacognitive training for schizophrenia patients (MCT) is a group intervention that seeks to sharpen the awareness of schizophrenia patients on cognitive biases (e.g. jumping to conclusions) that seem to underlie delusion formation and maintenance. The present trial combined group MCT with an individualized cognitive-behavioural therapy-oriented approach entitled individualized metacognitive therapy for psychosis (MCT+) and compared it against an active control.
A total of 48 patients fulfilling criteria of schizophrenia were randomly allocated to either MCT+ or cognitive remediation (clinical trial NCT01029067). Blind to intervention, both groups were assessed at baseline and 4 weeks later. Psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS) and the Psychotic Symptom Rating Scales (PSYRATS). Jumping to conclusions was measured using a variant of the beads task.
PANSS delusion severity declined significantly in the combined MCT treatment compared with the control condition. PSYRATS delusion conviction as well as jumping to conclusions showed significantly greater improvement in the MCT group. In line with prior studies, treatment adherence and subjective efficacy was excellent for the MCT.
The results suggest that the combination of a cognition-oriented and a symptom-oriented approach ameliorate psychotic symptoms and cognitive biases and represents a promising complementary treatment for schizophrenia.
PURPOSE OF REVIEWThere has been a marked increase in the study of cognitive biases in schizophrenia, which has in part been stimulated by encouraging results with cognitive–behavioral interventions ...in the disorder. We summarize new evidence on cognitive biases thought to trigger or maintain positive symptoms in schizophrenia and present a new therapeutic intervention.
RECENT FINDINGSRecent studies indicate that patients with paranoid schizophrenia jump to conclusions, show attributional biases, share a bias against disconfirmatory evidence, are overconfident in errors, and display problems with theory of mind. Many of these biases precede the psychotic episode and may represent cognitive traits. Building upon this literature, we developed a metacognitive training program that aims to convey scientific knowledge on cognitive biases to patients and provides corrective experiences in an engaging and supportive manner. Two new studies provide preliminary evidence for the feasibility and efficacy of this approach.
SUMMARYThe gap between our advanced understanding of cognitive processes in schizophrenia and its application in clinical treatment is increasingly being narrowed. Despite emerging evidence for the feasibility and efficacy of metacognitive training as a stand-alone program, its most powerful application may be in combination with individual cognitive–behavioral therapy.
Integrating evidence that contradicts a belief is a fundamental aspect of belief revision and is closely linked to delusions in schizophrenia. In a previous functional magnetic resonance imaging ...(fMRI) study on healthy individuals, we identified functional brain networks underlying evidence integration as visual attention network (VsAN; dorsal anterior cingulate cortex, insula, occipital regions), default-mode network (DMN), and cognitive evaluation network (CEN; orbitofrontal cortex, inferior frontal gyrus, parietal cortex). In the current clinical fMRI study, we compared network-based activity during evidence integration between healthy controls (n = 41), nondelusional (n = 37), and delusional (n = 33) patients with schizophrenia, and related this activity to cognitive processing involved in evidence integration measured outside the scanner. Task-induced coordinated activation was measured using group-constrained principal component analysis for fMRI. Increased VsAN activation, reduced DMN deactivation, and reduced CEN activation were observed for schizophrenia, with this pattern being most pronounced for the delusional group. Importantly, poor evidence integration comprehensively measured outside the scanner was significantly associated with increased VsAN activation and reduced DMN deactivation when processing confirmatory evidence, and with reduced CEN activation when processing disconfirmatory evidence. This is the first comprehensive study of the functional brain networks associated with evidence integration in schizophrenia and highlights how an imbalance of functional brain networks responding to confirmatory and disconfirmatory evidence may underlie delusions in schizophrenia.
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