Auditory processing and sensory behaviours in children with autism spectrum disorders as revealed by mismatch negativity

Sensory dysfunctions may underlie key characteristics in children with Autism Spectrum Disorders (ASD). The current study aimed to investigate auditory change detection in children with ASD in order to determine event-related potentials to meaningless and meaningful speech stimuli. 11 high functioning boys with a diagnosis of autism spectrum disorders (mean age = 13.0; SD = 1.08) and 11 typically developing boys (mean age = 13.7; SD = 1.5) participated in a mismatch negativity (MMN) paradigm. Results revealed that compared to TD controls, the children with ASD showed significantly reduced MMN responses to both words and pseudowords in the frontal regions of the brain and also a significant reduction in their activation for words in the Central Parietal regions. In order to test the relationship between sensory processing and auditory processing, children completed the Adult and Adolescent Sensory Profile. As predicted, the children with ASD showed more extreme sensory behaviours and were significantly higher than their typically developing controls across three of the sensory quadrants (sensory sensitivity, low registration and sensory avoidance). Importantly, only auditory sensory sensitivity was able to account for the differences displayed for words in the frontal and central parietal regions when controlling for the effect of group, revealing an inverse relationship of the higher sensory sensitivity scores the less activation in response for words. We discuss how the expression of sensory behaviours in ASD may result in deficient neurophysiological mechanisms underlying automatic language processing.     

Variance misperception explains illusions of confidence in simple perceptual decisions

Confidence in a perceptual decision is a judgment about the quality of the sensory evidence. The quality of the evidence depends not only on its strength (‘signal’) but critically on its reliability (‘noise’), but the separate contribution of these quantities to the formation of confidence judgments has not been investigated before in the context of perceptual decisions. We studied subjective confidence reports in a multi-element perceptual task where evidence strength and reliability could be manipulated independently. Our results reveal a confidence paradox: confidence is higher for stimuli of lower reliability that are associated with a lower accuracy. We show that the subjects’ overconfidence in trials with unreliable evidence is caused by a reduced sensitivity to stimulus variability. Our results bridge between the investigation of miss-attributions of confidence in behavioral economics and the domain of simple perceptual decisions amenable to neuroscience research.     

Thomas Bradwardine on God and the Foundations of Modality

Scholars have claimed that the fourteenth-century thinker Thomas Bradwardine held that God's will freely determined what was necessary, possible and impossible and in this regard, he was a medieval precursor to Descartes. In this article, I argue against this interpretation of Bradwardine. I show that Bradwardine held that objects derive their modal status based on whether God's necessary and immutable being isrepugnant or non-repugnant to their existence. I offer readings of thepassages in which Bradwardine appears to state that God's will determines modality that render them consistent with the non-voluntarist interpretation of his modal theory.     

The Red and The Real

It is often claimed that principles of individuation imply essential properties of the things individuated. For example, sets are individuated by their members, hence sets have their members essentially. But how does this inference work? First I discuss the form of such inferences, and conclude that the essentialist inference is not a purely formal matter: although there is a form which all principles of individuation have in common, it is not true that any statement of that form is a principle of individuation, and hence there is no valid inference based purely on that form. However, I argue that there is a viable version of the essentialist inference nonetheless. The resources for a proper reconstruction of this type of inference can be gathered from reflections upon the role principles of individuation play in the project of the ontologist: such principles turn out to carry a modal weight similar to that of definitions or conceptual truths. It follows that, no matter how austere the ontology, some portion of essentialist modality is inevitable.     

Conceptual Analysis and Philosophical Naturalism

Entitlement is conceived as a kind of positive epistemic status, attaching to certain propositions, that involves no cognitive or intellectual accomplishment on the part of the beneficiary—a status that is in place by default. In this paper I will argue that the notion of entitlement—or something very like it—falls out of an idea that may at first blush seem rather disparate: that the evidential support relation can be understood as a kind of variably strict conditional (in the sense of Lewis 1973). Lewis provided a general recipe for deriving what he termed inner modalities from any variably strict conditional governed by a logic meeting certain constraints. On my proposal, entitlement need be nothing more exotic than the inner necessity associated with evidential support. Understanding entitlement in this way helps to answer some common concerns—in particular, the concern that entitlement could only be a pragmatic, and not genuinely epistemic, status.     

Interstimulus Intervals and Sensory Modality Modulate the Impact of a Cognitive Task on Postural Control

The present literature not only reveals the use of a wide variety of cognitive tasks but variability in their interaction with postural control. The question then arises, as to, whether postural control is sensitive to specific features of a cognitive task. The present experiment assessed the impact of cognitive tasks with interstimulus intervals (ISI) of varied duration and sensory modality on postural control in young adults. Seventeen participants (23.71 ± 1.99 years old) were instructed to stand on a force platform while concurrently performing cognitive tasks with ISIs of two and 5 s. The tasks were presented both, auditorily and visually. The visual tasks consisted of counting the total occurrence of a single digit. The auditory tasks consisted of counting the total occurrence of a single letter. Performing the cognitive tasks with an ISI of 2 s resulted only in an increase in the anteroposterior mean power frequency. Presenting the tasks visually also significantly reduced area of 95% confidence ellipse and AP and mediolateral sway variability. These results may suggest that ISIs can modify postural performance by altering the allocation of attentional focus. Also, presenting tasks using a visual sensory modality appears to yield lower postural sway.     

Essence in abundance

Fine (1994 “Essence and Modality”, Philosophical Perspectives, 8: 1–16) is widely thought to have refuted the simple modal account of essence, which takes the essential properties of a thing to be those it cannot exist without exemplifying. Yet, a number of philosophers have suggested resuscitating the simple modal account by appealing to distinctions akin to the distinction Lewis (1983. “New Work For a Theory of Universals”, Australasian Journal of Philosophy, 61: 343–377; 1986. On the Plurality of Worlds. Oxford: Blackwell) draws between sparse and abundant properties, treating only those in the former class as candidates for essentiality. I argue that ‘sparse modalism’ succumbs to counterexamples similar to those originally posed by Fine, and fails to capture paradigmatic instances of essence involving abundant properties and relations.     

Bridging music and speech rhythm: Rhythmic priming and audio–motor training affect speech perception

Following findings that musical rhythmic priming enhances subsequent speech perception, we investigated whether rhythmic priming for spoken sentences can enhance phonological processing – the building blocks of speech – and whether audio–motor training enhances this effect. Participants heard a metrical prime followed by a sentence (with a matching/mismatching prosodic structure), for which they performed a phoneme detection task. Behavioural (RT) data was collected from two groups: one who received audio–motor training, and one who did not. We hypothesised that 1) phonological processing would be enhanced in matching conditions, and 2) audio–motor training with the musical rhythms would enhance this effect. Indeed, providing a matching rhythmic prime context resulted in faster phoneme detection, thus revealing a cross-domain effect of musical rhythm on phonological processing. In addition, our results indicate that rhythmic audio–motor training enhances this priming effect. These results have important implications for rhythm-based speech therapies, and suggest that metrical rhythm in music and speech may rely on shared temporal processing brain resources.     

The ecology of self-monitoring effects on memory of verbal productions: Does speaking to someone make a difference?

Experiments involving verbal self-monitoring show that memory for spoken words varies with types of sensory feedback: memory is better when words are spoken aloud than when they are lip-synched or covertly produced. Such effects can be explained by the Central Monitoring Theory (CMT) via a process that matches a forward model reflecting expected sensory effects of practiced forms and sensory information during speech. But CMT oversees factors of shared attention as achieved by speaker–listener gaze, and implies that sensory feedback may not affect the learning of unpracticed forms (non-words). These aspects of CMT were examined in two experiments of self-monitoring focusing on oro-sensory feedback. In Experiment 1 we show that varying feedback creates differential effects on memory for spoken words and that speaker–listener gaze alters these effects. Using non-words, Experiment 2 shows the absence of differential feedback effects. The results confirm CMT but suggest the need to refine the theory in terms of processes that mediate attention.     

The Relationship of Impulsiveness to Psychoticism and Extraversion in Elderly Psychiatric Patients

I conducted a correlational study to test the hypothesis that resource allocation outcomes become more favorable as uncertainty assessment accuracy (i.e., resolution and calibration) increases. For each of 32 college basketball games, participants predicted which team would win, estimated the subjective probability that their prediction was correct, and were given the opportunity to place a wager. The dependent variable was profit earned over the 32 bets. Proportion correct and mean certainty were controlled in the analyses. Results indicated that individuals with higher resolution scores earned significantly more profit than those with lower scores. Higher profits were also associated with better calibration.