SPEECH BEHAVIOUR—A FOUNDATION OF LANGUAGE SIMEON LOCKE Boston State Hospital A hierarchical view of the central nervous system suggests the principle that " lower level " activities are often recruited for utilization by subsequently evolved functions. In this view, speech, as distinguished from language, is a more automatic process in part responsive to perceptual input. It both shapes and is shaped by those aspects of language it serves.

The sustained interest in language, its philosophy, meaning, structure and function to its central position in human behaviour, and to man’s continuing effort to define himself. This central position, and the utilization of language as data for explorations of mind and culture, have led to the easy equation of language behaviour with specifically human attributes. The innateness of these attributes, and the presumed unique mechanisms underlying them, have been intuitively posited (Chomsky, 1968). Evidence in support of the intuition is elusive, although the notion, if correct, is clearly a particularly important one in understanding the position of human action in the biological realm. One means of access to the question of innateness of language and the unique mechanisms of its generation is provided by speech behaviour (as distinguished from language) which is viewed as a specific manifestation of more general behaviour and as a phenomenon that develops in advance of other aspects of language function. Speech, as behaviour, can be assumed to respond to the principles that govern other human motor performance, and can be visualized as having developed from a biological matrix by use of those principles which subvert earlier behavioural acquisitions. It consists of the phonological segmentation of earlier acquired vocalization. From the initial universal array of phonemes what are retained ultimately prove to be language specific members, while the &dquo; language inadmissible &dquo; members are discarded, never to be recovered even in neologisms or in the most severely regressed speech. The retained members are later endowed with meaning, placing speech at the disposal of language, as vocalization has been pressed into the service of speech. However speech also becomes evocative of language, as any low level function shapes the activity that grows out of it. Speech behaviour, like all behaviour, is released by adequate stimuli, and appears, when released, in aliquots. The adequacy of a releasing stimulus depends upon the level of development of the organism, its state at the time of stimulus presentation and the biological significance of the stimulus in the hierarchical array. What this means is that a focal lesion or other abnormality of the central nervous system affords opportunity, by changes in speech behaviour it produces, for deductions about the modules from which the architecture of speech, and ultimately of language, is

relate, surely,

produced. Studies in patients with schizophrenia, aphasia, and dementia (Locke et al. 1973) reveal that as these disorders constrict the function of the nervous system, so the


organism’s awareness of stimulus fields is constricted. The normal inhibitions imposed on speech behaviour, which prevent every intrusive percept from achieving utterance, are weakened in schizophrenia. The hyper-attentive state - really an inhibitory release is particularly evident with respect to the part of the &dquo; external world &dquo; that is recognized through the visual surround. Visual percepts find ready translation to utterances which then appear, independent of referent, as auditory percepts capable of being recycled. The auditory percepts, generated by the organism, rather than by the world around, are experienced by a sensory system much closer in texture and in cerebral localization to proprioceptive and postural modalities than is vision (Locke, 1961). As such this system presumably exploit low reflex mechanisms with recycling of input. In dementia, where reflex latitude is limited by the level of dissolution of function, repetition of an auditory percept is immediate and stereotyped. In schizophrenia, where manipulability is induced by selection from a stimulus array and there is ability to defer response, the recycling of auditory percepts eventuates in clang association. These data, derived from computer analysis of spontaneous verbal output of patients with schizophrenia, posterior aphasia, and the dementia of Alzheimer’s disease, underscore the interaction of the utterance and subsequent speech behaviour. The efficacy of vision as an initial releaser can be demonstrated in the same group of patients by the recording of spontaneous verbal output in an illuminated environment and in total darkness. The ratio of percentage of spontaneous speech (speech time/total time) in darkness to percentage of spontaneous speech in light demonstrates strikingly the relation between speech behaviour and visual input in schizophrenia, and the comparative independence of the two in the dementing diseases in which the auditory percept serves as a more potent releaser. The evocation of total parcels of behaviour, by a single stimulus, which has an analogue in insect physiology and which can be demonstrated by such things as spinal release in mammals, need not imply pre-determined behaviour. The fragmentation of total patterns by inhibition permits modulation by recombination of parts of the underlying reflexes to produce a virtually infinite repertory through recombination of finite parts - a generative system. The innateness of the performance, the principles which underlie it, and the rules predictive of further behaviour consist of the inherence of responsivity to releasing stimuli. Language bchaviour and the speech act in the behavioural sense - with illocutionary force determined by the context, presuppositions and assumptions inherent in the relationship between speaker and listener as well as by the syntax and semantic load of the sentence - depend ultimately on the neurological principles that govern the generation of the utterance. -


CHOMSKY, N. (1968). Language and Mind (New York). LOCKE, S. (1961). The projection of the magnocellular medial geniculate body. J. comp. Neur., 116, 179. LOCKE, S., CAPLAN, D. and KELLAR, L. (1973). A Study in Neurolinguistics (Springfield).

Speech behaviour--a foundation of language.

270 SPEECH BEHAVIOUR—A FOUNDATION OF LANGUAGE SIMEON LOCKE Boston State Hospital A hierarchical view of the central nervous system suggests the...
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