Online research in philosophy

Although sensorimotor contingencies may explain visual perception, it is difficult to extend this concept to speech perception. However, the basic concept of perception as active hypothesis testing using attention does extend well to speech perception. We propose that the concept of sensorimotor contingencies can be broadened to sensory-attentional contingencies, thereby accounting for speech perception as well as vision.

Contrary to Pothos, rule- and similarity-based processes cannot be distinguished by dimensionality. Rather, one must consider the goal of the processing: what the system will do with the resulting representations. Research on speech perception demonstrates that the degree to which speech categories are gradient (or similarity-based) is a function of the utility of within-category variation for further processing.

Inner speech represents the activity of talking to oneself in silence. It can be assessed with questionnaires, sampling methods, and electromyographic recordings of articulatory movements. Inner speech has been linked to thought processes and self-awareness. Private speech (speech-for-self emitted aloud by children) serves an important self-regulatory function. The frequency of private speech follows an inverted-U relation with age, peaking at 3-4 years of age and disappearing at age 10. Social and inner speech share a common neurological basis: Broca’s area. Dysfunctional self-talk is known to mediate many pathological conditions; negative selfverbalizations have a more significant debilitating impact than positive ones.

Locus equations contain an economical set of hidden (i.e., not directly observable in the data) parameters of speech that provide an elegant way of characterizing the ubiquitous context-dependent behaviors exhibited in speech acoustics. These hidden parameters can be effectively exploited to constrain the huge set of context-dependent speech model parameters currently in use in modern, mainstream speech recognition technology.

This chapter introduces debates about freedom of speech and argues that very few if any individuals support no restrictions whatsoever on freedom of speech. The question is therefore not should we restrict freedom of speech but rather what sorts of speech and how?

There is a thriving debate over what aspects of our capacity to produce and understand language are special. My concern here is a key part of this wider debate: Is speech special? In particular, my focus is on speech perception, and whether it is special. This isn’t just one but a number of different questions. Too frequently, these very different questions are not clearly distinguished and kept apart. I discuss a framework for distinguishing various versions of the question, Is speech perceptually special? Focusing on a particular class of questions, I make a proposal about the sense in which speech is perceptually special. According to this account, the capacity to perceive speech is an acquired perceptual skill, and involves learning to hear language-specific types of biologically-significant sounds. This account illuminates the significance of interlocution in understanding what makes the perception of speech distinctive.

This commentary questions the proposed resemblance between the auditory mechanisms of localization and those of the sensory registration of speech sounds. Comparative evidence, which would show that the neurophysiology of localization is adequate to the task of categorizing consonants, does not exist. In addition, Sussman et al. do not offer sensory or perceptual evidence to confirm the presence in humans of processes promoting phoneme categorization that are analogous to the neurophysiology of localization. Furthermore, the computational simulation of the linear model of second formant variation is not a plausible sensory mechanism for perceiving speech sounds.

Fodor argues that speech perception is accomplished by a module. Typically, modular processing is taken to be bottom-up processing. Yet there is ubiquitous empirical evidence that speech perception is influenced by top-down processing. Fodor attempts to resolve this conflict by denying that modular processing must be exclusively bottom-up. It is argued, however, that Fodor's attempt to reconcile top-down and modular processing fails, because: (i) it undermines Fodor's own conception of modular processing; and (ii) it cannot account for the contextually varying top-down influences that characterize speech perception.

In this paper I provide a metatheoretical analysis of speech perception research. I argue that the central turning point in the history of speech perception research has not been well understood. While it is widely thought to mark a decisive break with what I call "the alphabetic conception of speech," I argue that it instead marks the entrenchment of this conception of speech. In addition, I argue that the alphabetic conception of speech continues to underwrite speech perception research today and moreover that it functions as a dogma which ought to be rejected.