Social eye gaze modulates processing of speech and co-speech gesture

In human face-to-face communication, language comprehension is a multi-modal, situated activity. However, little is known about how we combine information from different modalities during comprehension, and how perceived communicative intentions, often signaled through visual signals, influence this process. We explored this question by simulating a multi-party communication context in which a speaker alternated her gaze between two recipients. Participants viewed speech-only or speech + gesture object-related messages when being addressed (direct gaze) or unaddressed (gaze averted to other participant). They were then asked to choose which of two object images matched the speaker’s preceding message. Unaddressed recipients responded significantly more slowly than addressees for speech-only utterances. However, perceiving the same speech accompanied by gestures sped unaddressed recipients up to a level identical to that of addressees. That is, when unaddressed recipients’ speech processing suffers, gestures can enhance the comprehension of a speaker’s message. We discuss our findings with respect to two hypotheses attempting to account for how social eye gaze may modulate multi-modal language comprehension.     

Testing the difficulty theory of the SON‐R –17, a non‐verbal test of intelligence

Fischer's (1973) linear logistic test model can be used to test hypotheses regarding the effect of covariates on item difficulty and to predict the difficulty of newly constructed test items. However, its assumptions of equal discriminatory power across items and a perfect prediction of item difficulty are never absolutely met. The amount of misfit in an application of a Bayesian version of the model to two subtests of the SON‐R –17 is investigated by means of item fit statistics in the framework of posterior predictive checks and by means of a comparison with a model that allows for residual (co)variance in the item parameters. The effect of the degree of residual (co)variance on the robustness of inferences is investigated in a simulation study.     

Reliance,Trust, and Belief

Abstract

An adequate theory of the nature of belief should help us explain the most obvious features of belief as we find it. Among these features are: guiding action and reasoning non-inferentially; varying in strength in ways that are spontaneously experience-sensitive; ‘aiming at truth’ in some sense and being evaluable in terms of correctness and warrant; possessing inertia across time and constancy across contexts; sustaining expectations in a manner mediated by propositional content; shaping the formation and execution of plans; generalizing spontaneously projectively; and being independent of the will and resisting instrumentalization. Using the method of ‘creature construction’, I attempt to show how we can build an attitude with these features step-by-step from simpler components, thereby avoiding the problems of regress or circularity affecting a number of influential accounts of belief.     

The effect of psychological stress and expectation on auditory perception: A signal detection analysis

Both psychological stress and predictive signals relating to expected sensory input are believed to influence perception, an influence which, when disrupted, may contribute to the generation of auditory hallucinations. The effect of stress and semantic expectation on auditory perception was therefore examined in healthy participants using an auditory signal detection task requiring the detection of speech from within white noise. Trait anxiety was found to predict the extent to which stress influenced response bias, resulting in more anxious participants adopting a more liberal criterion, and therefore experiencing more false positives, when under stress. While semantic expectation was found to increase sensitivity, its presence also generated a shift in response bias towards reporting a signal, suggesting that the erroneous perception of speech became more likely. These findings provide a potential cognitive mechanism that may explain the impact of stress on hallucination‐proneness, by suggesting that stress has the tendency to alter response bias in highly anxious individuals. These results also provide support for the idea that top‐down processes such as those relating to semantic expectation may contribute to the generation of auditory hallucinations.