Measurement practices in hallucinations research

Introduction In several sub-fields of psychology, there has been a renewed focus on measurement practices. As far as we are aware, this has been absent in hallucinations research. Thus, we investigated (a) cross-study variation in how hallucinatory experiences are measured and (b) the reliability of measurements obtained using two tasks that are widely employed in hallucinations research. Method In Study 1, we investigated to what extent there was variation in how the Launay-Slade Hallucination Scale (LSHS) has been used across 100 studies. In Study 2, we investigated the reliability of the measurements obtained through source monitoring and signal detection tasks, using data from four recent publications. Materials/data are available at doi: 10.17605/osf.io/d3gnk/. Results In Study 1, we found substantial variation in how hallucinatory experiences were assessed using the LSHS and that descriptions of the LSHS were often incomplete in important ways. In Study 2, we reported a range of reliability estimates for the measurements obtained using source monitoring and signal discrimination tasks. Some measurements obtained using source monitoring tasks had unacceptably low levels of reliability. Conclusions Our findings suggest that suboptimal measurement practices are common in hallucinations research and we suggest steps researchers could take to improve measurement practices

Multivariate analysis of the dominant and sub-dominant epipelic diatoms and water quality data from South African rivers

Data are presented on the distribution of the dominant and sub-dominant epipelic diatoms found in South African rivers from different regions of the country. A multivariate analysis identified 36 diatom species that were associated with different levels of TDS, PO4, NH4 and SiO2. Three groups of rivers were identified. Group I consisted of sites with high PO4 and SiO2, which corresponded to Durban Metropolitan Area sites, Kruger National Park rivers, the rivers in the Johannesburg Metropolitan Area and the Orange River. In these rivers 12 diatom species were identified that might  indicate those water quality characteristics. Group II included stations where the water quality had high TDS and NH4 values which were associated with most stations in the Swartkops River in the Eastern Cape. The indicators in this group comprised 12 diatom species. Group III were from sampling stations where the water had low levels of minerals, i.e. the upper reaches of the Gamtoos River and the Swartkops River in the Eastern Cape, the Olifants River in the Northern Cape, rivers sampled in KwaZulu-Natal and the Northern Cape. At these sites, 13 diatom species were found as dominants in this better water quality. Water quality data collected during this study showed that over 50% of the river systems display some degree of eutrophication and thus efforts should be made to reduce inputs of nutrients and pollutants to those rivers.Keywords: ammonium, diatoms, phosphate, rivers, South Africa, total dissolved solid

The brain’s conversation with itself: neural substrates of dialogic inner speech

Inner speech has been implicated in important aspects of normal and atypical cognition, including the development of auditory hallucinations. Studies to date have focused on covert speech elicited by simple word or sentence repetition, while ignoring richer and arguably more psychologically significant varieties of inner speech. This study compared neural activation for inner speech involving conversations (‘dialogic inner speech’) with single-speaker scenarios (‘monologic inner speech’). Inner speech-related activation differences were then compared with activations relating to Theory-of-Mind (ToM) reasoning and visual perspective-taking in a conjunction design. Generation of dialogic (compared with monologic) scenarios was associated with a widespread bilateral network including left and right superior temporal gyri, precuneus, posterior cingulate and left inferior and medial frontal gyri. Activation associated with dialogic scenarios and ToM reasoning overlapped in areas of right posterior temporal cortex previously linked to mental state representation. Implications for understanding verbal cognition in typical and atypical populations are discussed

Evaluation of core loss calculation methods for highly non-sinusoidal inputs

A modular, hybrid HVDC transformer, located in the turbine nacelle has been proposed for the offshore wind industry to improve efficiency and redundancy while reducing costs. The injection of harmonics by the transformer power electronics however, complicates the core loss calculations of such a transformer. The standard Steinmetz Equation is no longer valid and the alternative loss equations proposed in the literature are significantly more complicated. Therefore, many in the industry still use the Steinmetz Equation with the signal's Fourier Transform. However, the literature suggests this to be inaccurate without quantifying it. This paper will therefore compare the accuracy of this approach to a prominent alternative presented in the literature, the improved Generalised Steinmetz Equation

Developing inclusive pedagogies in HE through an understanding of the learner-consumer : promiscuity, hybridisation, and innovation

Abstract: This article contributes to debates about how to respond to the changing profile of Higher Education (HE) students, and the marketisation of HE, by challenging prevailing views about student engagement, in order to develop learner-centric and inclusive pedagogies which are relevant to the twenty-first century. The concepts of ‘participatory culture’ and ‘co-creativity’ are often associated with the digital world in which the current generation of students have grown up. But it is a mistake to assume that some learning styles are inherently more participatory than others: participation is not an effect of the medium or form, (analog vs digital), or the space (actual vs virtual), or the mode of interaction a (face-to-face vs networked) through which the learner participates – it is an effect of the practices involved. Students engage with a complex network of both digital and analog texts and spaces, and it is this postdigital hybrid setting within which student engagement takes place. Marketisation provides an opportunity to actively demonstrate our commitments to student-centredness and inclusive practice, by transcending the binary opposition between ‘Student as Partner’ and ‘Student as Consumer’ and recognizing that students are learner-consumers, and allowing students’ diversity to drive innovation, rather than continuing to disempower students by bolstering practices which privilege some learning styles above others, informed by the assumption that innovation is technology-led

Anomalous visual experience is linked to perceptual uncertainty and visual imagery vividness

An imbalance between top-down and bottom-up processing on perception (specifically, over-reliance on top-down processing) can lead to anomalous perception, such as illusions. One factor that may be involved in anomalous perception is visual mental imagery, which is the experience of “seeing” with the mind’s eye. There are vast individual differences in self-reported imagery vividness, and more vivid imagery is linked to a more sensory-like experience. We, therefore, hypothesized that susceptibility to anomalous perception is linked to individual imagery vividness. To investigate this, we adopted a paradigm that is known to elicit the perception of faces in pure visual noise (pareidolia). In four experiments, we explored how imagery vividness contributes to this experience under different response instructions and environments. We found strong evidence that people with more vivid imagery were more likely to see faces in the noise, although removing suggestive instructions weakened this relationship. Analyses from the first two experiments led us to explore confidence as another factor in pareidolia proneness. We, therefore, modulated environment noise and added a confidence rating in a novel design. We found strong evidence that pareidolia proneness is correlated with uncertainty about real percepts. Decreasing perceptual ambiguity abolished the relationship between pareidolia proneness and both imagery vividness and confidence. The results cannot be explained by incidental face-like patterns in the noise, individual variations in response bias, perceptual sensitivity, subjective perceptual thresholds, viewing distance, testing environments, motivation, gender, or prosopagnosia. This indicates a critical role of mental imagery vividness and perceptual uncertainty in anomalous perceptual experience. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00426-020-01364-7) contains supplementary material, which is available to authorized users