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Fulltext Randomised prior feedback modulates neural signals of outcome monitoring

Mushtaq F, Wilkie RM, Mon-Williams MA, Schaefer A

Neuroimage, 2016 Jan 15;125:868-879.
PMID: 26497268 DOI: 10.1016/j.neuroimage.2015.10.046

Substantial evidence indicates that decision outcomes are typically evaluated relative to expectations learned from relatively long sequences of previous outcomes. This mechanism is thought to play a key role in general learning and adaptation processes but relatively little is known about the determinants of outcome evaluation when the capacity to learn from series of prior events is difficult or impossible. To investigate this issue, we examined how the feedback-related negativity (FRN) is modulated by information briefly presented before outcome evaluation. The FRN is a brain potential time-locked to the delivery of decision feedback and it is widely thought to be sensitive to prior expectations. We conducted a multi-trial gambling task in which outcomes at each trial were fully randomised to minimise the capacity to learn from long sequences of prior outcomes. Event-related potentials for outcomes (Win/Loss) in the current trial (Outcomet) were separated according to the type of outcomes that occurred in the preceding two trials (Outcomet-1 and Outcomet-2). We found that FRN voltage was more positive during the processing of win feedback when it was preceded by wins at Outcomet-1 compared to win feedback preceded by losses at Outcomet-1. However, no influence of preceding outcomes was found on FRN activity relative to the processing of loss feedback. We also found no effects of Outcomet-2 on FRN amplitude relative to current feedback. Additional analyses indicated that this effect was largest for trials in which participants selected a decision different to the gamble chosen in the previous trial. These findings are inconsistent with models that solely relate the FRN to prediction error computation. Instead, our results suggest that if stable predictions about future events are weak or non-existent, then outcome processing can be determined by affective systems. More specifically, our results indicate that the FRN is likely to reflect the activity of positive affective systems in these contexts. Importantly, our findings indicate that a multifactorial explanation of the nature of the FRN is necessary and such an account must incorporate affective and motivational factors in outcome processing.
Fulltext Preferences for intervention among Peruvian women in intimate partner violence relationships

Cripe SM, Espinoza D, Rondon MB, Jimenez ML, Sanchez E, Ojeda N, et al.

Hisp Health Care Int, 2015;13(1):27-37.
PMID: 25741931 DOI: 10.1891/1540-4153.13.1.27

We sought to identify what abused Peruvian women want or need as intervention strategies. We conducted five focus groups with 30 women with prior or current experience with intimate partner violence. Participants noted that abused women need compassionate support, professional counseling, and informational and practical (e.g., work skills training, employment, shelter, financial support) interventions. We propose a 2-tiered intervention strategy that includes community support groups and individual professional counseling. This strategy is intended to offer broad coverage, meeting the needs of large groups of women who experience abuse, whereas providing specialized counseling for those requiring intensive support. Respect for each woman's autonomy in the decision-making process is a priority. Interventions targeted toward women and men should address structural factors that contribute to violence against women.
Fulltext Feedback-related potentials in a gambling task with randomised reward

Mushtaq F, Guillen PP, Wilkie RM, Mon-Williams MA, Schaefer A

Data Brief, 2016 Mar;6:378-85.
PMID: 26862585 DOI: 10.1016/j.dib.2015.11.060

Event-related potentials (ERPs) time-locked to decision outcomes are reported. Participants engaged in a gambling task (see [1] for details) in which they decided between a risky and a safe option (presented as different coloured shapes) on each trial (416 in total). Each decision was associated with (fully randomised) feedback about the reward outcome (Win/Loss) and its magnitude (varying as a function of decision response; 5-9 points for Risky decisions and 1-4 points for Safe decisions). Here, we show data demonstrating: (a) the influence of Win feedback in the preceding outcome (Outcome t-1) on activity related to the current outcome (Outcome t ); (b) difference wave analysis for outcome expectancy- separating Expected Outcomes (consecutive Loss trials subtracted from consecutive reward) from Unexpected Outcomes (subtracting Loss t-1Win t trials from Win t-1Loss t trials); (c) difference waves separating Switch and Stay responses for Outcome Expectancy; (d) the effect of magnitude induced by decisions (Risk t vs. Safe t ) on Outcome Expectancy; and finally, (e) expectations reflected by response switch direction (Risk to Safe responses vs. Safe to Risk t ) on the FRN at Outcome t .
Fulltext Frontal theta brain activity varies as a function of surgical experience and task error

Balkhoyor AM, Awais M, Biyani S, Schaefer A, Craddock M, Jones O, et al.

BMJ Surg Interv Health Technol, 2020;2(1):e000040.
PMID: 35047792 DOI: 10.1136/bmjsit-2020-000040

OBJECTIVE: Investigations into surgical expertise have almost exclusively focused on overt behavioral characteristics with little consideration of the underlying neural processes. Recent advances in neuroimaging technologies, for example, wireless, wearable scalp-recorded electroencephalography (EEG), allow an insight into the neural processes governing performance. We used scalp-recorded EEG to examine whether surgical expertise and task performance could be differentiated according to an oscillatory brain activity signal known as frontal theta-a putative biomarker for cognitive control processes.
DESIGN SETTING AND PARTICIPANTS: Behavioral and EEG data were acquired from dental surgery trainees with 1 year (n=25) and 4 years of experience (n=20) while they performed low and high difficulty drilling tasks on a virtual reality surgical simulator. EEG power in the 4-7 Hz range in frontal electrodes (indexing frontal theta) was examined as a function of experience, task difficulty and error rate.
RESULTS: Frontal theta power was greater for novices relative to experts (p=0.001), but did not vary according to task difficulty (p=0.15) and there was no Experience × Difficulty interaction (p=0.87). Brain-behavior correlations revealed a significant negative relationship between frontal theta and error in the experienced group for the difficult task (r=-0.594, p=0.0058), but no such relationship emerged for novices.
CONCLUSION: We find frontal theta power differentiates between surgical experiences but correlates only with error rates for experienced surgeons while performing difficult tasks. These results provide a novel perspective on the relationship between expertise and surgical performance.
Fulltext Comparative performance of Patient Health Questionnaire-9 and Edinburgh Postnatal Depression Scale for screening antepartum depression

Zhong Q, Gelaye B, Rondon M, Sánchez SE, García PJ, Sánchez E, et al.

J Affect Disord, 2014 Jun;162:1-7.
PMID: 24766996 DOI: 10.1016/j.jad.2014.03.028

OBJECTIVE: We sought to evaluate the psychometric properties of two widely used screening scales: the Patient Health Questionnaire (PHQ-9) and Edinburgh Postnatal Depression Scale (EPDS) among pregnant Peruvian women.
METHODS: This cross-sectional study included 1517 women receiving prenatal care from February 2012 to March 2013. A structured interview was used to collect data using PHQ-9 and EPDS. We examined reliability, construct and concurrent validity between two scales using internal consistency indices, factor structures, correlations, and Cohen׳s kappa.
RESULTS: Both scales had good internal consistency (Cronbach׳s alpha>0.8). Correlation between PHQ-9 and EPDS scores was fair (rho=0.52). Based on exploratory factor analysis (EFA), both scales yielded a two-factor structure. EFA including all items from PHQ-9 and EPDS yielded four factors, namely, "somatization", "depression and suicidal ideation", "anxiety and depression", and "anhedonia". The agreement between the two scales was generally fair at different cutoff scores with the highest Cohen׳s kappa being 0.46.
CONCLUSIONS: Both the PHQ-9 and EPDS are reliable and valid scales for antepartum depression assessment. The PHQ-9 captures somatic symptoms, while EPDS detects depressive symptoms comorbid with anxiety during early pregnancy. Our findings suggest simultaneous administration of both scales may improve identification of antepartum depressive disorders in clinical settings.
Fulltext Chemical compounds from anthropogenic environment and immune evasion mechanisms: potential interactions

Kravchenko J, Corsini E, Williams MA, Decker W, Manjili MH, Otsuki T, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S111-27.
PMID: 26002081 DOI: 10.1093/carcin/bgv033

An increasing number of studies suggest an important role of host immunity as a barrier to tumor formation and progression. Complex mechanisms and multiple pathways are involved in evading innate and adaptive immune responses, with a broad spectrum of chemicals displaying the potential to adversely influence immunosurveillance. The evaluation of the cumulative effects of low-dose exposures from the occupational and natural environment, especially if multiple chemicals target the same gene(s) or pathway(s), is a challenge. We reviewed common environmental chemicals and discussed their potential effects on immunosurveillance. Our overarching objective was to review related signaling pathways influencing immune surveillance such as the pathways involving PI3K/Akt, chemokines, TGF-β, FAK, IGF-1, HIF-1α, IL-6, IL-1α, CTLA-4 and PD-1/PDL-1 could individually or collectively impact immunosurveillance. A number of chemicals that are common in the anthropogenic environment such as fungicides (maneb, fluoxastrobin and pyroclostrobin), herbicides (atrazine), insecticides (pyridaben and azamethiphos), the components of personal care products (triclosan and bisphenol A) and diethylhexylphthalate with pathways critical to tumor immunosurveillance. At this time, these chemicals are not recognized as human carcinogens; however, it is known that they these chemicalscan simultaneously persist in the environment and appear to have some potential interfere with the host immune response, therefore potentially contributing to promotion interacting with of immune evasion mechanisms, and promoting subsequent tumor growth and progression.
Evaluation of multiple breast cancer polygenic risk score panels in women of Latin American heritage

Huang X, Lott PC, Hu D, Zavala VA, Jamal ZN, Vidaurre T, et al.

Cancer Epidemiol Biomarkers Prev, 2024 Dec 03.
PMID: 39625644 DOI: 10.1158/1055-9965.EPI-24-1247

BACKGROUND: A substantial portion of the genetic predisposition for breast cancer is explained by multiple common genetic variants of relatively small effect. A subset of these variants, which have been identified mostly in individuals of European and Asian ancestry, have been combined to construct a polygenic risk score (PRS) to predict breast cancer risk, but the prediction accuracy of existing PRSs in Hispanic/Latinx individuals (H/L) remain relatively low. We assessed the performance of several existing PRS panels with and without addition of H/L specific variants among self-reported H/L women.
METHODS: PRS performance was evaluated using multivariable logistic regression and the area under the receiver operating characteristic curve (AUC).
RESULTS: Both European and Asian PRSs performed worse in H/L samples compared to original reports. The best European PRS performed better than the best Asian PRS in pooled H/L samples. European PRSs had decreased performance with increasing Indigenous American (IA) ancestry while Asian PRSs had increased performance with increasing IA ancestry. The addition of 2 H/L SNPs increased performance for all PRSs, most notably in the samples with high IA ancestry and did not impact the performance of PRSs in individuals with lower IA ancestry.
CONCLUSIONS: A single PRS that incorporates risk variants relevant to the multiple ancestral components of individuals from Latin America, instead of a set of ancestry specific panels, could be used in clinical practice.
IMPACT: Results highlight the importance of population-specific discovery and suggest a straightforward approach to integrate ancestry specific variants into PRS for clinical application.
Fulltext Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead

Goodson WH, Lowe L, Carpenter DO, Gilbertson M, Manaf Ali A, Lopez de Cerain Salsamendi A, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S254-96.
PMID: 26106142 DOI: 10.1093/carcin/bgv039

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology.