Initial elevation bias in subjective reports.

People's reports of their thoughts, feelings, and behaviors are used in many fields of biomedical and social science. When these states have been studied over time, researchers have often observed an unpredicted and puzzling decrease with repeated assessment. When noted, this pattern has been called an "attenuation effect," suggesting that the effect is due to bias in later reports. However, the pattern could also be consistent with an initial elevation bias. We present systematic, experimental investigations of this effect in four field studies (study 1: n = 870; study 2: n = 246; study 3: n = 870; study 4: n = 141). Findings show clear support for an initial elevation bias rather than a later decline. This bias is larger for reports of internal states than for behaviors and for negative mental states and physical symptoms than for positive states. We encourage increased awareness and investigation of this initial elevation bias in all research using subjective reports.

Phenomenological features of dreams: Results from dream log studies using the Subjective Experiences Rating Scale (SERS).

Self-ratings of dream experiences were obtained from 144 college women for 788 dreams, using the Subjective Experiences Rating Scale (SERS). Consistent with past studies, dreams were characterized by a greater prevalence of vision, audition, and movement than smell, touch, or taste, by both positive and negative emotion, and by a range of cognitive processes. A Principal Components Analysis of SERS ratings revealed ten subscales: four sensory, three affective, one cognitive, and two structural (events/actions, locations). Correlations (Pearson r) among subscale means showed a stronger relationship among the process-oriented features (sensory, cognitive, affective) than between the process-oriented and content-centered (structural) features--a pattern predicted from past research (e.g., Bulkeley & Kahan, 2008). Notably, cognition and positive emotion were associated with a greater number of other phenomenal features than was negative emotion; these findings are consistent with studies of the qualitative features of waking autobiographical memory (e.g., Fredrickson, 2001).

Subjective report of eye fixations during serial search.

Humans readily introspect upon their thoughts and their behavior, but how reliable are these subjective reports? In the present study, we explored the consistencies of and differences between the observer's subjective report and actual behavior within a single trial. On each trial of a serial search task, we recorded eye movements and the participants' beliefs of where their eyes moved. The comparison of reported versus real eye movements revealed that subjects successfully reported a subset of their eye movements. Limits in subjective reports stemmed from both the number and the type of eye movements. Furthermore, subjects sometimes reported eye movements they actually never made. A detailed examination of these reports suggests that they could reflect covert shifts of attention during overt serial search. Our data provide quantitative and qualitative measures of observers' subjective reports and reveal experimental effects of visual search that would otherwise be inaccessible.

Objective Nebuliser Adherence Data as "Proof" of Adherence in the Management of Cystic Fibrosis: A Qualitative Interview Study.

Purpose: Low adherence to medication via nebulisers is linked to poor clinical outcomes for people with Cystic Fibrosis (PWCF). Advances in technology allow electronic monitoring of nebuliser usage and feedback of objective adherence data to PWCF and clinical teams caring for them. CFHealthHub is a new intervention that collects and displays objective adherence data in easy-to-read formats with the aim of improving nebuliser adherence and health. There is little understanding of how objective adherence data is perceived by PWCF and healthcare professionals (HCPs). Patients and Methods: A qualitative study using semi-structured interviews with 22 PWCF and 31 HCPs who had used the CFHealthHub intervention. Results: Objective adherence data was welcomed by the majority of PWCF in the sample, and HCP delivering the intervention, because the data allowed PWCF to reflect on patterns of adherence or non-adherence. Ease of use and characteristics of data display were important, particularly the use of a "traffic light" system to allow PWCF to easily see if they were meeting their adherence targets. For PWCF objective adherence data was used as "proof to self", offering reassurance to high adherers, and a wake-up call to those with lower levels of adherence. It could also provide 'proof to others' where PWCF had higher levels of adherence than HCP or family members believed. The data could sometimes change HCP perceptions of PWCF's identities as poor adherers. Where adherence was not high, data was used to facilitate honest discussions between PWCF and HCPs about how to increase adherence. HCPs perceived that it was important to use the data positively to motivate, rather than criticise, PWCF. Conclusion: Objective nebuliser adherence data in CFHealthHub can offer proof of adherence to PWCF and HCPs. It is important to use it constructively to facilitate discussions on how to improve adherence.

The Influence of Affective State on Subjective-Report Measurements: Evidence From Experimental Manipulations of Mood.

A substantial portion of the knowledge base of psychology is based on subjective reports with a risk of information bias. The objective of the present study was to elucidate one contextual source of variance and potential bias in subjective reports: the influence of affective state at the time of responding to questionnaires. Employees (N = 67, abstaining from stimulants and activities that may influence emotional and physiological state) were subjected to mood-induction procedures in the laboratory. Neutral, positive, and negative moods were induced by combinations of pictures from the international affective picture set (IAPS) and music. The subjects responded to questions on visual analog scales (VAS) in order to optimize sensitivity and attenuate short-term memory effects. Most subjects exhibited significant affective-state inductions with no change in arousal. The analyses took affective response to the manipulation into account. Only four of 20 questions were somewhat influenced by induced affective state: job overload, social support from co-workers, satisfaction with getting to develop personally, and an item measuring agreeableness. In general, responding to questions of work that were phrased for valence was little or insignificantly influenced by induced affective state.

Relationship among subjective responses, flavor, and chemical composition across more than 800 commercial cannabis varieties.

BACKGROUND: Widespread commercialization of cannabis has led to the introduction of brand names based on users' subjective experience of psychological effects and flavors, but this process has occurred in the absence of agreed standards. The objective of this work was to leverage information extracted from large databases to evaluate the consistency and validity of these subjective reports, and to determine their correlation with the reported cultivars and with estimates of their chemical composition (delta-9-THC, CBD, terpenes). METHODS: We analyzed a large publicly available dataset extracted from Leafly.com where users freely reported their experiences with cannabis cultivars, including different subjective effects and flavour associations. This analysis was complemented with information on the chemical composition of a subset of the cultivars extracted from Psilabs.org . The structure of this dataset was investigated using network analysis applied to the pairwise similarities between reported subjective effects and/or chemical compositions. Random forest classifiers were used to evaluate whether reports of flavours and subjective effects could identify the labelled species cultivar. We applied Natural Language Processing (NLP) tools to free narratives written by the users to validate the subjective effect and flavour tags. Finally, we explored the relationship between terpenoid content, cannabinoid composition and subjective reports in a subset of the cultivars. RESULTS: Machine learning classifiers distinguished between species tags given by "Cannabis sativa" and "Cannabis indica" based on the reported flavours: = 0.828 ± 0.002 (p < 0.001); and effects: = 0.9965 ± 0.0002 (p < 0.001). A significant relationship between terpene and cannabinoid content was suggested by positive correlations between subjective effect and flavour tags (p < 0.05, False-Discovery-rate (FDR)-corrected); these correlations clustered the reported effects into three groups that represented unpleasant, stimulant and soothing effects. The use of predefined tags was validated by applying latent semantic analysis tools to unstructured written reviews, also providing breed-specific topics consistent with their purported subjective effects. Terpene profiles matched the perceptual characterizations made by the users, particularly for the terpene-flavours graph (Q = 0.324). CONCLUSIONS: Our work represents the first data-driven synthesis of self-reported and chemical information in a large number of cannabis cultivars. Since terpene content is robustly inherited and less influenced by environmental factors, flavour perception could represent a reliable marker to indirectly characterize the psychoactive effects of cannabis. Our novel methodology helps meet demands for reliable cultivar characterization in the context of an ever-growing market for medicinal and recreational cannabis.

A model of subjective report and objective discrimination as categorical decisions in a vast representational space.

Subliminal perception studies have shown that one can objectively discriminate a stimulus without subjectively perceiving it. We show how a minimalist framework based on Signal Detection Theory and Bayesian inference can account for this dissociation, by describing subjective and objective tasks with similar decision-theoretic mechanisms. Each of these tasks relies on distinct response classes, and therefore distinct priors and decision boundaries. As a result, they may reach different conclusions. By formalizing, within the same framework, forced-choice discrimination responses, subjective visibility reports and confidence ratings, we show that this decision model suffices to account for several classical characteristics of conscious and unconscious perception. Furthermore, the model provides a set of original predictions on the nonlinear profiles of discrimination performance obtained at various levels of visibility. We successfully test one such prediction in a novel experiment: when varying continuously the degree of perceptual ambiguity between two visual symbols presented at perceptual threshold, identification performance varies quasi-linearly when the stimulus is unseen and in an 'all-or-none' manner when it is seen. The present model highlights how conscious and non-conscious decisions may correspond to distinct categorizations of the same stimulus encoded by a high-dimensional neuronal population vector.