The Motor Theory of Speech Perception is a proposed explanation of the fundamental relationship between the way speech is produced and the way it is perceived. Associated primarily with the work of Liberman and colleagues, it posited the active participation of the motor system in the perception of speech. Early versions of the theory contained elements that later proved untenable, such as the expectation that the neural commands to the muscles (as seen in electromyography) would be more invariant than the acoustics. Support drawn from categorical perception (in which discrimination is quite poor within linguistic categories but excellent across boundaries) was called into question by studies showing means of improving within-category discrimination and finding similar results for nonspeech sounds and for animals perceiving speech. Evidence for motor involvement in perceptual processes nonetheless continued to accrue, and related motor theories have been proposed. Neurological and neuroimaging results have yielded a great deal of evidence consistent with variants of the theory, but they highlight the issue that there is no single “motor system,” and so different components appear in different contexts. Assigning the appropriate amount of effort to the various systems that interact to result in the perception of speech is an ongoing process, but it is clear that some of the systems will reflect the motor control of speech.
D. H. Whalen
Irit Meir and Oksana Tkachman
Iconicity is a relationship of resemblance or similarity between the two aspects of a sign: its form and its meaning. An iconic sign is one whose form resembles its meaning in some way. The opposite of iconicity is arbitrariness. In an arbitrary sign, the association between form and meaning is based solely on convention; there is nothing in the form of the sign that resembles aspects of its meaning. The Hindu-Arabic numerals 1, 2, 3 are arbitrary, because their current form does not correlate to any aspect of their meaning. In contrast, the Roman numerals I, II, III are iconic, because the number of occurrences of the sign I correlates with the quantity that the numerals represent. Because iconicity has to do with the properties of signs in general and not only those of linguistic signs, it plays an important role in the field of semiotics—the study of signs and signaling. However, language is the most pervasive symbolic communicative system used by humans, and the notion of iconicity plays an important role in characterizing the linguistic sign and linguistic systems. Iconicity is also central to the study of literary uses of language, such as prose and poetry. There are various types of iconicity: the form of a sign may resemble aspects of its meaning in several ways: it may create a mental image of the concept (imagic iconicity), or its structure and the arrangement of its elements may resemble the structural relationship between components of the concept represented (diagrammatic iconicity). An example of the first type is the word cuckoo, whose sounds resemble the call of the bird, or a sign such as RABBIT in Israeli Sign Language, whose form—the hands representing the rabbit's long ears—resembles a visual property of that animal. An example of diagrammatic iconicity is vēnī, vīdī, vīcī, where the order of clauses in a discourse is understood as reflecting the sequence of events in the world. Iconicity is found on all linguistic levels: phonology, morphology, syntax, semantics, and discourse. It is found both in spoken languages and in sign languages. However, sign languages, because of the visual-gestural modality through which they are transmitted, are much richer in iconic devices, and therefore offer a rich array of topics and perspectives for investigating iconicity, and the interaction between iconicity and language structure.
Susanne Fuchs and Peter Birkholz
Consonants are a major class of sounds occurring in all human languages. Typologically, consonant inventories are richer than vowel inventories. Consonants have been classified according to four basic features. Airstream mechanism is one of these features and describes the direction of airflow in or out of the oral cavity. The outgoing airflow is further separated according to its origin, that is, air coming from the lungs (pulmonic) or the oral cavity (non-pulmonic). Consonants are also grouped according to their phonological voicing contrast, which can be manifested phonetically by the presence or absence of vocal fold oscillations during the oral closure/constriction phase and by the duration from an oral closure release to the onset of voicing. Place of articulation is the third feature and refers to the location at which a consonantal constriction or closure is produced in the vocal tract. Finally, manner of articulation reflects different timing and coordinated actions of the articulators closely tied to aerodynamic properties.
There are two main theoretical traditions in semantics. One is based on realism, where meanings are described as relations between language and the world, often in terms of truth conditions. The other is cognitivistic, where meanings are identified with mental structures. This article presents some of the main ideas and theories within the cognitivist approach. A central tenet of cognitively oriented theories of meaning is that there are close connections between the meaning structures and other cognitive processes. In particular, parallels between semantics and visual processes have been studied. As a complement, the theory of embodied cognition focuses on the relation between actions and components of meaning. One of the main methods of representing cognitive meaning structures is to use images schemas and idealized cognitive models. Such schemas focus on spatial relations between various semantic elements. Images schemas are often constructed using Gestalt psychological notions, including those of trajector and landmark, corresponding to figure and ground. In this tradition, metaphors and metonymies are considered to be central meaning transforming processes. A related approach is force dynamics. Here, the semantic schemas are construed from forces and their relations rather than from spatial relations. Recent extensions involve cognitive representations of actions and events, which then form the basis for a semantics of verbs. A third approach is the theory of conceptual spaces. In this theory, meanings are represented as regions of semantic domains such as space, time, color, weight, size, and shape. For example, strong evidence exists that color words in a large variety of languages correspond to such regions. This approach has been extended to a general account of the semantics of some of the main word classes, including adjectives, verbs, and prepositions. The theory of conceptual spaces shows similarities to the older frame semantics and feature analysis, but it puts more emphasis on geometric structures. A general criticism against cognitive theories of semantics is that they only consider the meaning structures of individuals, but neglect the social aspects of semantics, that is, that meanings are shared within a community. Recent theoretical proposals counter this by suggesting that semantics should be seen as a meeting of minds, that is, communicative processes that lead to the alignment of meanings between individuals. On this approach, semantics is seen as a product of communication, constrained by the cognitive mechanisms of the individuals.