The Return of Fear: Variation of the Serotonin Transporter Gene Predicts Outcome of a Highly Standardized Exposure-Based One-Session Fear Treatment.

BACKGROUND: Methodological problems of existing research, such as the application of unstandardized treatments in heterogeneous samples, has hampered clear conclusions about the extent and direction to which allelic variation of the serotonin transporter gene-linked polymorphic region (5- HTTLPR) is associated with a differential response to psychological treatment. The present study aimed to investigate the effects of the 5-HTTLPR genotype on treatment outcome under highly standardized environmental conditions. METHODS: We treated 222 medication-free adults highly fearful of spiders, dental surgeries or blood, injuries and injections with a highly standardized exposure-based 1-session treatment and genotyped them for the 5-HTTLPR. Participants' subjective fear was assessed before, immediately after treatment and at 7 months of follow-up. RESULTS: There were no differences between 5-HTTLPR genotypes in treatment outcome effects at the immediate posttreatment assessment. However, we observed a highly significant genotype × treatment effect (p = 0.004) at the 7-month follow-up. Fear levels of homozygous S allele carriers differed from those heterozygous (p = 0.026) and homozygous (p = 0.012) for the L allele. Compared to posttreatment assessment, LL allele carriers exhibited a further fear decrease at the follow-up assessment. In contrast, SS allele carriers displayed a strong return of fear. CONCLUSIONS: Results suggest that genetic variation of the serotonin transporter is associated with differential stability of inhibitory learning processes, potentially reflecting heightened susceptibility for context-related processes that facilitate a return of fear in S allele carriers. If replicated, results suggest the 5-HTTLPR might represent a biomarker for the long-term outcome of brief exposure-based fear treatments and might inform genotype-based selection of psychotherapeutic interventions.

DNA methylation levels of the serotonin transporter gene are not associated with the outcome of highly standardized one-session exposure-based fear treatment.

Epigenetic alterations are regarded as a potential mechanism mediating the effects of environmental risk factors on vulnerability for a range of mental health problems. Recent studies have addressed the question whether DNA methylation patterns predict the outcome of psychological interventions and whether treatment effects might be associated with changes of DNA methylation. We assessed phobic fear symptoms, treatment-relevant traits and treatment response in 308 adults free of psychotropic medication - highly fearful of either spiders, blood-injury-injections, dental-treatments or heights - all subjected to highly standardized exposure-based one-session fear treatment. DNA methylation level of the promotor region of the serotonin transporter gene (SLC6A4) was assessed in either saliva samples (spider and dental treatment fear cohorts) or oral mucosa (BII, heights) to check whether possible effects are independent of the surrogate tissue examined. Moreover, in order to examine possible DNA methylation by genotype effects, patients were assessed for genetic variation of the serotonin transporter-linked polymorphic region (5-HTTLPR). DNA methylation levels were neither associated with pre-treatment fear levels, treatment relevant traits or treatment outcome data even when allelic variation of the 5HTTLPR was considered. Overall DNA methylation levels were higher in saliva samples compared to buccal samples. In saliva samples there was a small pre- to post-treatment increase in DNA methylation, which, however, was also not associated with the investigated phenotypes. We conclude that DNA methylation of SLC6A4 is no suitable biomarker for response efficacy to highly standardized one-session exposure-based fear treatments.

Stability and durability of salivary alpha-amylase across different storage conditions.

Data collection in remote and field settings gains importance and popularity in stress research. Accordingly, existing stress induction paradigms have been successfully adapted to remote and field settings. However, guidelines for the comprehensive assessment of biomarkers such as salivary alpha-amylase (sAA) have yet to be sufficiently established for such contexts. In remote and field settings, swift freezing of saliva samples is not always possible, and samples must be returned to the laboratory for further processing. The current study investigated the robustness of sAA activity against external factors that may affect measurements obtained from saliva samples collected in field and remote settings. We compared sAA activity of samples that were stored in different vials (Salivettes® and Eppendorf® vials) and that were exposed to (1) up to three cycles of freezing and thawing, (2) different temperatures (4 °C, 20 °C, 30 °C, and 40 °C) for 3, 7, 14, or 28 days, or that were (3) sent via postal delivery. Results indicate sAA activity to be susceptible across different temperatures, different time intervals, and different vials. As a systematic pattern, sAA activity seems to decrease in treated samples with this effect being potentiated by more extreme conditions such as higher temperatures and longer time intervals. To conclude, sAA data collected in remote or field settings could be affected systematically by various external variables. Future studies collecting sAA should take factors influencing the durability and stability of sAA into account to ensure reliable and valid measurements of salivary data.

Integrated microRNA and mRNA gene expression in peripheral blood mononuclear cells in response to acute psychosocial stress: a repeated-measures within-subject pilot study.

OBJECTIVE: The impact of psychosocial stress on a variety of negative health outcomes is well documented, with current research efforts directed at possible mechanisms. Here, we focused on a potential mechanism involving differential expression of mRNA and microRNA in response to acute psychosocial stress. We utilized a validated behavioral paradigm, the Trier Social Stress Test (TSST), to induce acute psychosocial stress in a cohort of volunteers. Stress reactivity was assessed repeatedly during the TSST using saliva samples that were analyzed for levels of cortisol. Peripheral blood mononuclear cells were extracted from blood drawn at baseline and at two time points following the stress paradigm. Total RNA was extracted, and mRNA and microRNA microarrays were utilized to assess within-subject changes in gene expression between baseline and the two post-stressor time points. RESULTS: For microarray gene expression analysis, we focused on 12 participants who showed a robust cortisol response to the task, as an indicator of robust HPA-axis activation. We discovered a set of mRNAs and miRNAs that exhibited dynamic expression change in response to the TSST in peripheral blood mononuclear cells, further characterizing the link between psychosocial stress and cellular response mechanisms.

Genes in treatment: Polygenic risk scores for different psychopathologies, neuroticism, educational attainment and IQ and the outcome of two different exposure-based fear treatments.

OBJECTIVES: Evidence for a genetic influence on psychological treatment outcome so far has been inconsistent, likely due to the focus on candidate genes and the heterogeneity of the disorders treated. Using polygenic risk scores (PRS) in homogenous patient samples may increase the chance of detecting genetic influences. METHODS: A sample of 342 phobic patients treated either for clinically relevant dental fear (n = 189) or other (mixed) phobic fears (n = 153) underwent highly standardised exposure-based CBT. A brief five-session format was used to treat dental fear, whereas longer multi-session treatments were used with the mixed-fear cohort. PRS were calculated based on large genetic studies of Neuroticism, Educational Attainment (EA), Intelligence, and four psychopathology domains. We compared PRS of post-treatment and follow-up remitters and non-remitters and regressed PRS on fear reduction percentages. RESULTS: In the dental fear cohort, EA PRS were associated with treatment outcomes, i.e. drop-out, short- and long-term remission state, fear reduction, and attendance of subsequent dental appointments. In the mixed fear treatment cohort, no gene effects were observable. CONCLUSIONS: Results indicate the importance of EA-related traits for outcomes following brief, but not long, standardised exposure-based CBT. Such use of PRS may help inform selection and tailoring of treatments.

Event-related functional MRI of awake behaving pigeons at 7T.

Animal-fMRI is a powerful method to understand neural mechanisms of cognition, but it remains a major challenge to scan actively participating small animals under low-stress conditions. Here, we present an event-related functional MRI platform in awake pigeons using single-shot RARE fMRI to investigate the neural fundaments for visually-guided decision making. We established a head-fixated Go/NoGo paradigm, which the animals quickly learned under low-stress conditions. The animals were motivated by water reward and behavior was assessed by logging mandibulations during the fMRI experiment with close to zero motion artifacts over hundreds of repeats. To achieve optimal results, we characterized the species-specific hemodynamic response function. As a proof-of-principle, we run a color discrimination task and discovered differential neural networks for Go-, NoGo-, and response execution-phases. Our findings open the door to visualize the neural fundaments of perceptual and cognitive functions in birds-a vertebrate class of which some clades are cognitively on par with primates.

Cortisol modulates the engagement of multiple memory systems: Exploration of a common NR3C2 polymorphism.

Exposure to acute stress has been shown to result in a shift from declarative toward non-declarative learning, presumably mediated by brain mineralocorticoid receptors (MRs). In this study, we aimed to replicate and extend these findings by investigating the role of stress-associated cortisol secretion on learning behavior. Furthermore, we explored the influence of a well-characterized common single nucleotide polymorphism of the MR gene (rs2070951; minor allele frequency: 49.3%) previously shown to influence MR expression and HPA axis activity. Healthy males (n = 74) were exposed to the Trier Social Stress Test or a control condition prior to performing a probabilistic classification task (Weather Prediction Task). The use of a non-declarative learning strategy continuously increased over the course of the learning task after stress exposure, but leveled in the control condition. The shift toward a non-declarative strategy in the stress group was associated with better learning performance. Higher pre-stress cortisol levels favored the adoption of a non-declarative learning strategy. rs2070951 C/C-carriers in contrast to G-allele carriers exhibited a larger secretion of cortisol under stress. Furthermore, control participants homozygous for the C-allele adopted a non-declarative learning strategy less often than stressed participants, whereas the choice of strategy was independent of stress in G-allele carriers. The failure to switch strategies resulted in poorer performance, suggesting a beneficial effect of stress in dependence of MR variation. Consistent with previous findings, the results provide further support for cortisol as a driving force in coordinating the competition between multiple memory systems under stress.

Mechanisms, genes and treatment: Experimental fear conditioning, the serotonin transporter gene, and the outcome of a highly standardized exposure-based fear treatment.

There is considerable interindividual variation in response to psychotherapeutical intervention. In order to realize the long-term goal of personalised treatment approaches, it is important to identify behavioural and biological moderators and mediators of treatment responses. Here, we tested the predictive value of experimental fear extinction efficacy as well as the role of genetic variation of the serotonin transporter gene for the outcome of a fear-exposure treatment. A discriminative fear conditioning paradigm was conducted in 159 adults highly fearful of spiders, dental surgeries or blood, injuries and injections. Participants were genotyped for the long (L) and short (S) allelic variant of the serotonin transporter gene linked polymorphic region (5HTTLPR) and treated with a highly standardized exposure-based one-session treatment. Participants' subjective fear was assessed during experimental fear conditioning and extinction. Furthermore, subjective phobic fear was assessed at pre-, post and at 7 months follow-up treatment assessment. A threat-biased contingency learning pattern characterized by exaggerated fear responses to the CS- was associated with larger initial subjective fear reduction immediately following the large-group treatment, p = .03. There were no learning pattern-associated differences in subjective fear at 7-month follow-up. The odds of homozygous s-allele carriers to display a threat-biased contingency learning pattern were 3.85 times larger compared to l-allele carriers, p = .01. Fear-recovery in homozygous S-allele carriers at follow-up assessment, p = .01, emerged regardless of the experimental fear acquisition pattern. Our results suggest the homozygous S-allele carriers are biologically biased towards ignoring safety signals in threat-related situations. Short-term, this response pattern might be positively related to the outcome of exposure treatments, potentially due to increased responding to safe context conditions or a stronger violation of threat expectancies. However, alterations in inhibiting the response to cues formerly signalling threat evidenced for S-allele carriers can have negative impact on exposure success.

HPA axis dysregulation in adult adoptees twenty years after severe institutional deprivation in childhood.

Hypothalamic-pituitary-adrenal (HPA) axis function is disrupted in institutionally-deprived children - reduced morning cortisol, flattened diurnal slope and blunted reactivity persist even after successful adoption into positive family environments. Here we test whether such effects persist into adulthood. Cortisol release across the day (sampled at awakening, 30 and 45min later, and at four points across the day) was investigated in young adult adoptees who had lived in severe deprivation for up to 43 months in early childhood in Ceaușescu's Romanian orphanages and a comparison group of non-deprived UK adoptees (Total N=57; mean age=24±0.9years). The mediating role of cortisol levels on adult mental health was examined using data from standardized clinical assessments. Cortisol profiles were disrupted in the Romanian adoptees who experienced more than 6 months deprivation marked by a striking absence of the cortisol awakening response (CAR) and a significantly flatter cortisol curve until 1h 15min after awakening. Whereas institutional deprivation was associated with both cortisol secretion and emergence of emotional problems in young adulthood, path analysis revealed no evidence for a mediating role of CAR disruption in the sub-sample studied here. The results are in line with findings of HPA axis hypo-functionality following early adverse experience and provide strong evidence for long-term programming effects of HPA axis function through experience of institutional deprivation.