Task-dependent functional connectivity changes in response to varying levels of social support.

BACKGROUND: Having social support improves one's health outcomes and self-esteem, and buffers the negative impact of stressors. Previous studies have explored the association between social support and brain activity, but evidence from task-dependent functional connectivity is still limited. AIMS: We aimed to explore how gradually decreasing levels of social support influence task-dependent functional connectivity across several major neural networks. METHOD: We designed a social support task and recruited 72 young adults from real-life social groups. Of the four members in each group, one healthy participant (18 participants in total) completed the functional magnetic resonance imaging (fMRI) scan. The fMRI task included three phases with varying levels of social support: high-support phase, fair phase and low-support phase. Functional connectivity changes according to three phases were examined by generalised psychophysiological interaction analysis. RESULTS: The results of the analysis demonstrated that participants losing expected support showed increased connectivity among salience network, default mood network and frontoparietal network nodes during the fair phase compared with the high-support phase. During the low-support phase, participants showed increased connectivity among only salience network nodes compared with the high-support phase. CONCLUSIONS: The results indicate that the loss of support was perceived as a threat signal and induced widespread increased functional connectivity within brain networks. The observation of significant functional connectivity changes between fair and high-support phases suggests that even a small loss of social support from close ones leads to major changes in brain function.

The Effect of Aging on Face-Name Recognition: An fMRI Study. / Yaslanmanin Yüz ve Isim Tanima Üzerindeki Etkisi: Bir fMRG Çalismasi.

OBJECTIVE: The aim of this study is to detect functional changes in the brain during the memory task with aging and the association between functional changes and memory performance. METHOD: The study consisted of Young Adult Group (YAG, n=20) aged 20 to 25 and Late Adult Group (LAG, n=18) aged 60 to 70. Individuals with Montreal Cognitive Assessment (MoCA) scores above 21 and no family history of Alzheimer's Disease were included in the study. Functional Magnetic Resonance Imaging (fMRI) scanning was performed on all participants during a memory task including encoding (face and name), face and name recognition sub-tasks. RESULTS: Results indicated that LAG showed increased activity during face recognition task in left posterior cingulate cortex, left superior frontal cortex, left fusiform face area and another increased activity was found out during name recognition task in left superior frontal cortex, right prefrontal cortex, left anterior + posterior cingulate cortex. The accuracy of face recognition and name recognition memory tests were significantly lower in LAG (respectively, p=0.026; p=0.001). CONCLUSION: These results indicated that advanced age were associated with more widespread activation in brain during memory task. Thus with aging, individuals require more neuronal and cognitive resources during memory processing.

The effect of emotional faces on reward-related probability learning in depressed patients.

BACKGROUND: Existing research indicates that individuals with Major Depressive Disorder (MDD) exhibit a bias toward salient negative stimuli. However, the impact of such biased stimuli on concurrent cognitive and affective processes in individuals with depression remains inadequately understood. This study aimed to investigate the effects of salient environmental stimuli, specifically emotional faces, on reward-associated processes in MDD. METHODS: Thirty-three patients with recurrent MDD and thirty-two healthy controls (HC) matched for age, sex, and education were included in the study. We used a reward-related associative learning (RRAL) task primed with emotional (happy, sad, neutral) faces to investigate the effect of salient stimuli on reward-related learning and decision-making in functional magnetic resonance imaging (fMRI). Participants were instructed to ignore emotional faces during the task. The fMRI data were analyzed using a full-factorial general linear model (GLM) in Statistical Parametric Mapping (SPM12). RESULTS: In depressed patients, cues primed with sad faces were associated with reduced amygdala activation. However, both HC and MDD group exhibited reduced ventral striatal activity while learning reward-related cues and receiving rewards. LIMITATIONS: The patients'medication usage was not standardized. CONCLUSIONS: This study underscores the functional alteration of the amygdala in response to cognitive tasks presented with negative emotionally salient stimuli in the environment of MDD patients. The observed alterations in amygdala activity suggest potential interconnected effects with other regions of the prefrontal cortex. Understanding the intricate neural connections and their disruptions in depression is crucial for unraveling the complex pathophysiology of the disorder.

Gradual Loss of Social Group Support during Competition Activates Anterior TPJ and Insula but Deactivates Default Mode Network.

Group forming behaviors are common in many species to overcome environmental challenges. In humans, bonding, trust, group norms, and a shared past increase consolidation of social groups. Being a part of a social group increases resilience to mental stress; conversely, its loss increases vulnerability to depression. However, our knowledge on how social group support affects brain functions is limited. This study observed that default mode network (DMN) activity reduced with the loss of social group support from real-life friends in a challenging social competition. The loss of support induced anterior temporoparietal activity followed by anterior insula and the dorsal attentional network activity. Being a part of a social group and having support provides an environment for high cognitive functioning of the DMN, while the loss of group support acts as a threat signal and activates the anterior temporoparietal junction (TPJ) and insula regions of salience and attentional networks for individual survival.

Emotional context effect on recognition of varying facial emotion expression intensities in depression.

BACKGROUND: Previous research has indicated that Major Depressive Disorder (MDD) patients have deficits in the process of facial emotion recognition. In most of these studies, isolated emotional faces were used, and the effect of the surrounding context of the face was neglected. We aimed to investigate how context emotion (sad or happy) affects facial emotion recognition and whether this effect is different in depressive individuals compared to the control group. METHODS: Happy, sad, neutral facial expressions with congruent and incongruent visual contexts were presented to 51 MDD patients and 42 matched healthy controls. Emotional facial expressions are presented as morphs gradually expressing happiness or sadness with 40% and 80% intensity levels. Mean reaction time, mean accuracy rate, and mean emotion intensity rating score was calculated for each condition. RESULTS: The performances on facial emotion intensity rating and accuracy rate were similar between MDD patients and controls. MDD patients were slower to recognize all facial emotions and to recognize facial emotions with emotionally incongruent backgrounds compared to congruent ones. LIMITATIONS: Antidepressant therapy of patients might have affected our results. CONCLUSIONS: Emotional contextual features have an important role in facial emotion recognition but this effect is independent of depression. Longer reaction time in depression may be related to some cognitive impairments.

[Investigation of Microsporidia prevalence with calcofluor white and uvitex 2B chemiluminescence staining methods and molecular analysis of species in diarrheal patients]. / Ishalli olgularda Microsporidia sikliginin Calcofluor beyazi ve uvitex 2B kemiluminesans boyama yöntemleriyle arastirilmasi ve türlerinin moleküler yöntemle tiplendirilmesi.

Microsporidia, obligate intracellular parasites, were first defined by Nageli in 1857. Microsporidia phylum consists of 200 genus and 1500 species. They have a wide host spectrum including insects, fish, and mammals. It has been shown that they may also infect humans and may be existed both in symptomatic and asymptomatic forms. There are eight species infecting humans, which include Anncaliia (Brachiola, Nosema), Encephalitozoon, Entrocytozoon, Microsporidium, Nosema, Pleistophora, Trachipleistophor, and Vittaforma. The species most commonly infect humans are Encephalitozoon intestinalis and Enterocytozoon bieneusi. The aim of this study was to determine the prevalence of Microsporidia by using two different chemiluminescence stains, namely uvitex 2B and calcoflour and detect species by molecular analysis in diarrheal patients. For this purpose, we studied stool samples of 200 patients with diarrhea sent to Gazi University Health Practice and Research Hospital, Microbiology Laboratory and Ankara Numune Training and Research Hospital Microbiology Laboratory between 2012-2013. The stool samples were stained with chemiluminescent stains uvitex 2B and calcoflour methods; the Microsporidia prevalence was found to be 38% (77/200) by fluorescent microscopic examination. Statistically an excellent consistency was found between the chemiluminescent stains uvitex 2B and calcoflour (Cohen's kappa= 0.881). A statistical analysis for the consistency of uvitex 2B and calcoflour in terms of numerical density (low, high) and luminescence of spores (dim, bright) showed a moderate consistency between the two stains with respect to determining numerical density of spores (Cohen's kappa= 0.354), while there was no consistency in terms of luminescence of spores (Cohen's Kappa= 0.001). No significant difference was found between the Microsporidia prevalence with respect to age group or clinics (p > 0.05). A sex-based analysis showed that Microsporidia prevalence was more common in women (50%) than men (30.8%) (p< 0.05). In 77 samples that were detected positive for Microsporidia with uvitex 2B and calcoflour stains determination of genus and species level were done by using multiplex nested polymerase chain reaction (PCR) method. With this technique, seven (9.1%) of 77 isolates were detected as E.bieneusi, and 70 (90.9%) as Encephalitozoon spp. When the Microsporidia genus was considered, the Microsporidia prevalence did not show differences with respect to age, sex, and referring clinics (p> 0.05). In our study 44 (62.9%) of 70 Encephalitozoon spp. were E.intestinalis, 22 (31.4%) were E.cuniculi, and 4 (5.7%) were E. hellem. No statistical difference was found in the distribution of Encephalitozoon spp. with age, sex, and referring clinic (p> 0.05). We concluded that examination of stool samples with the chemiluminescent stain uvitex 2B and/or calcoflour would be useful for the initial stage of Microsporidia diagnosis; furthermore, the multiplex nested PCR method was considered useful for determination of genus and species. In our country, there is a small number of molecular reports about Microsporidia prevalence in stool samples. Molecular methods should be used more commonly for the evaluation of treatment options in diarrheal patients and detection of Microsporidia epidemiology.

Genetic imaging study with [Tc-99m] TRODAT-1 SPECT in adolescents with ADHD using OROS-methylphenidate.

AIM: To examine theeffects on the brain of 2-month treatment withamethylphenidate extended-release formulation (OROS-MPH) using [Tc-99m] TRODAT-1SPECT in a sample of treatment-naïve adolescents with Attention Deficit/Hyperactivity Disorder (ADHD). In addition, to assess whether risk alleles (homozygosity for 10-repeat allele at the DAT1 gene were associated with alterations in striatal DAT availability. METHODS: Twenty adolescents with ADHD underwent brain single-photon emission computed tomography (SPECT) scans with [Tc-99m] TRODAT-1 at baseline and two months after starting OROS-MPH treatment with dosages up to 1 mg/kg/day. Severity of illness was estimated using the Clinical Global Impression Scale (CGI-S) and DuPaul ADHD Rating Scale-Clinician version (ARS) before treatment,1 month and 2 months after initiating OROS-MPH treatment. RESULTS: Decreased DAT availability was found in both the right caudate (pretreatment DAT binding: 224.76 ±â€¯33.77, post-treatment DAT binding: 208.86 ±â€¯28.75, p = 0.02) and right putamen (pre-treatment DAT binding: 314.41 ±â€¯55.24, post-treatment DAT binding: 285.66 ±â€¯39.20, p = 0.05) in adolescents with ADHD receiving OROS-MPH treatment. Adolescents with ADHD who showed a robust response to OROS-MPH (n = 7) had significantly greater reduction of DAT density in the right putamen than adolescents who showed less robust response to OROS-MPH (n = 13) (p = 0.02). However, between-group differences by treatment responses were not related with DAT density in the right caudate. Risk alleles (homozygosity for the 10-repeat allele of DAT1 gene) in the DAT1 gene were not associated with alterations in striatal DAT availability. CONCLUSION: Two months of OROS-MPH treatment decreased DAT availability in both the right caudate and putamen. Adolescents with ADHD who showed a robust response to OROS-MPH had greater reduction of DAT density in the right putamen. However,our findings did not support an association between homozygosity for a 10-repeat allele in the DAT1 gene and DAT density, assessedusing[Tc-99m] TRODAT-1SPECT.

Robust activation detection methods for real-time and offline fMRI analysis.

We propose two contributions with novel approaches to fMRI activation analysis. The first is to apply confidence intervals to locate activations in real-time, and second is a new metric based on robust regression of fMRI signals. These contributions are implemented in our four proposed methods; Instantaneous Activation Method (IAM), Instantaneous Activation Method with Past Blocks (IAMP) for real-time analysis, Task Robust Regression Distance Method (TRRD) for the new metric with robust regression and Instantaneous Robust Regression Distance Method (IRRD) for both contributions. For comparison, a statistical offline method called Task Activation Method (TAM) and a correlation analysis method are also implemented. The methods are initially evaluated with synthetic data generated using two different approaches; first using varying hemodynamic response function signals to simulate a wide range of stimuli responses, along with a Gaussian white noise, and second using no activity state data of a real fMRI experiment, which removes the need to generate noise. The methods are also tested with real fMRI experiments and compared with the results obtained by the widely used SPM tool. The results show that instantaneous methods reveal activations that are lost statistically in an offline analysis. They also reveal further improvements by robust fitting application, which minimizes the outlier effect. TRRD has an area under the ROC curve of 0,7127 for very noisy synthetic images, is reaching up to 0,9608 as the noise decreases, while the instantaneous score is in the range of 0,6124 to 0,8019 in the same noise levels.

The relationship between childhood trauma, emotion recognition, and irritability in schizophrenia patients.

This study investigated the relationship between childhood trauma, irritability, and emotion recognition, in schizophrenia patients during a psychotic break. Thirty-six schizophrenia inpatients and 36 healthy controls were assessed with the Irritability Questionnaire (IRQ) and two facial emotion recognition tasks, the Emotion Discrimination Test (EDT) and Emotion Identification Test (EIT). Patients were further assessed with the Structured Clinical Interview for DSM III-R Axis II Disorders (SCID-II), the Positive and Negative Symptom Scale (PANSS), and the Childhood Trauma Questionnaire-28 (CTQ-28). EDT and EIT performance was significantly impaired in patients compared to healthy controls. Furthermore, patients tended to misidentify sad, surprised, or angry faces as showing fear, and this misidentification correlated with the patients' irritability. Childhood adversity increased irritability both directly and indirectly through emotion misidentification.

Facial emotion recognition in remitted depressed women.

Although major depressive disorder (MDD) is primarily characterized by mood symptoms, depressed patients have impairments in facial emotion recognition in many of the basic emotions (anger, fear, happiness, surprise, disgust and sadness). On the other hand, the data in remitted MDD (rMDD) patients is inconsistent and it is not clear that if those impairments persist in remission. To extend the current findings, we applied facial emotion recognition test to a group of remitted depressed women and compared to those of controls. Analyses of variance results showed a significant emotion and group interaction, and in the post hoc analyses, rMDD patients had higher accuracy rate for recognition of sadness compared to those of controls. There were no differences in the reaction time among the patients and controls across the all the basic emotions. The higher recognition rates for sad faces in rMDD patients might contribute to the impairments in social communication and the prognosis of the disease.

Reduced left uncinate fasciculus fractional anisotropy in deficit schizophrenia but not in non-deficit schizophrenia.

AIMS: Schizophrenia is a psychiatric disorder manifesting with heterogeneous symptom clusters and clinical presentations. The deficit syndrome is the condition defined by the existence of primarily negative symptoms, and patients with the deficit syndrome differ from non-deficit patients on measures of brain structure and function. In the current study, by using diffusion tensor imaging (DTI), we investigated the frontotemporal connectivity that is hypothesized to differ between deficit and non-deficit schizophrenia. METHODS: Twenty-nine patients and 17 healthy controls were included in the study. The patients had deficit (n = 11) or non-deficit (n = 18) schizophrenia and they were evaluated clinically with the Schedule for Deficit Syndrome (SDS) and Positive and Negative Syndrome Scale (PANSS). Diffusion-based images were obtained with a 1.5T Siemens Magnetic Resonance Imaging machine and analyses were carried out with Functional Magnetic Resonance Imaging of the Brain Library Software - Diffusion tool box software. RESULTS: The fractional anisotropy values in the left uncinate fasciculus of schizophrenia patients with the deficit syndrome were lower than those of non-deficit patients and the controls. There were no differences between non-deficit schizophrenia patients and controls. CONCLUSION: These findings provide evidence of left uncinate fasciculus damage resulting in disrupted communication between orbitofrontal prefrontal areas and temporal areas in deficit schizophrenia patients.