Dimensions for classifying spontaneous speech

After spontaneously produced speech is classified into social and private speech, most private speech studies go on to classify the private speech utterances on the basis of one or more dimensions of speech (Winsler et al., 2005). The various dimensions which form the basis of classification can be the physical or structural form of speech (e.g., degree of overtness or internalisation), the content of speech utterance (e.g., task-relevance and semantic content) or the context of speech (e.g., speech/conversational acts). There is no consensus yet on any one dimension being the most appropriate basis of classifying speech. However, the choice of the dimension which will form the basis of classification of speech in a study is crucial in correctly addressing a particular research question.

The various categories derived from these dimensions of speech, and the studies which have employed them, are described below. One of the major methodological issues in private speech research is the confusion between the various dimensions of speech, such that one dimension of speech (e.g., level of internalisation) is assumed to also represent another dimension of speech (e.g., task-relevance). This issue has also been elaborated below along with solutions for avoiding this confusion in new systems of classification.

2.5.3.1 Structural form of speech

While tracing the ontogenetic developmental trajectory of private speech, researchers (Berk, 1986; Kohlberg et al., 1968; Manning & White, 1990) found a rise in overt private speech utterances, reaching a peak during preschool years (3-5 years) and then declining gradually, appearing to be replaced by partially audible and semi-internalised whisperings and finally inaudible mutterings and lip movements by early primary school. Thus the levels of overtness of private speech have been assumed to represent the relative maturity or immaturity of private speech. Based on these findings, many private speech studies classified speech according to the dimension of structural form of speech, and its degree of overtness in particular. Hence they classified private speech into the following three categories, in descending order of internalisation of speech - loud or overt speech, semi-internalised whispers, and inaudible mutterings (Alarcon-Rubio et al., 2014; Berk, 1986; Fernyhough & Fradley, 2005; Kohlberg et al., 1968; Kraft & Berk, 1998; Lidstone, Meins & Fernyhough, 2011; Ostad & Sorensen, 2007; Winsler et al., 2000). Most of these studies usually reported correlation between speech categories with higher level of internalisation and conditions that either require more advanced behaviour, i.e. a difficult task level, or other measures of greater

behavioural control. Hence internalisation of private speech was proposed to be associated with advances in regulation of behaviour.

2.5.3.2 Content of speech

The dimension of content encompasses different aspects of speech content, such as task-relevance, semantic content and pragmatic content. Classification based on task-relevance usually involves assessing the content of the speech for its direct relation to the task at hand. Hence while statements about objects and events related to the task as well as evaluations of one’s performance or task difficulty may be classified as task-relevant speech, utterances such as word-play, repetitive sounds, singing and affective expressions are usually considered to be task-irrelevant. This system of classification is usually clubbed together with classification based on the form of speech, i.e., the degree of overtness of speech (Berk, 1986). The problem with classifying form and content of speech together under a single system of categorisation has been discussed later in Section 2.5.3.4.

Early on in the private speech tradition, methodologies which focused solely on the quantity or frequency of private speech utterances while examining their relation to mediation of behaviour were criticised (Frawley & Lantolf, 1986; Wretch, 1979) for ignoring the quality or content of the speech utterances, which might be more influential in determining how task-relevant behaviour is mediated by speech (refer to Section 2.3.2 for a discussion on this issue). Hence, more studies in this tradition started classifying speech based on its semantic content, wherein several mutually exclusive and exhaustive categories were employed based on ‘what is said’ in the speech utterance (Berk & Spuhl, 1995; Copeland, 1979; Diaz et al., 1992; Kraft & Berk, 1998; Damianova et al., 2012; Rubin & Dyck, 1980; Winsler, 1998; Winsler et al., 2003). In these studies, particular semantic categories such as future-oriented statements about the task, commands, questions referring to task-related objects and events were shown to be correlated with task-relevant behavioural measures or more advanced level of behavioural control in other situations. Hence the particular content of private speech was proposed to be associated with certain aspects of self- regulatory behaviour, under the assumption that the specific task-related content of an utterance may have a real-time mediatory effect on an aspect of task-related behaviour that accompanies the utterance. However, correlation findings can only assume real-time occurrence, while also being limited in examining the particular but ever-changing contexts in which such co-occurrences of speech and behaviour take place (refer to Section 2.5.6 for a discussion on the limitations of correlational findings).

2.5.3.3 Context of speech

While the examination of the semantic content of speech is certainly a step forward in focusing on the role of the qualitative aspects of speech in verbal mediation of behaviour, such classifications are not able to distinguish between ‘what is said’ and ‘what is meant’ by the speaker within a conversation, situated in a particular context. Several researchers have argued that Vygostky’s conceptualisation of verbal mediation of behaviour through private speech was primarily based on the effect that the meaning of the utterances had on behaviour rather than simply their rate of production (Feigenbaum, 2002; Frawley & Lantolf, 1986; Wretch, 1979). Further, according to Vygotsky, even the meaning of an utterance is not fixed or constant, but is dynamically created out of the movement between the act of thinking and the act of communication in words (Feigenbaum, 2002). Classifications of speech based on semantic analysis examine the semantic and syntactical aspects of individual speech utterances, divorced from the interactive and dynamic meaning-making context in which utterances are produced as a part of a turn-taking conversational structure. For example, utterances produced in the syntactical form of a question, such as - “Why don’t you give it a try?” may be classified as a question in a system based solely on the semantic content and syntactical structure of speech. However, when seen in the context of the entire conversation within which such an utterance is produced, it is clear that the utterance is a statement directing or suggesting someone to do something rather than asking them the reason for not making an attempt to do it. If more information about the speaker and the listener is also taken into consideration, one can further clarify that such an utterance was meant to be a command (albeit in a polite and encouraging conversational style) rather than a suggestion, if the speaker was a teacher directing a child to tidy-up a play area which the child had initially refused on the pretext that it was a difficult task. This example proves that features such as the intention of the speaker, the context in which the utterance is produced, and the conversational style and skills of the speaker are crucial in establishing ‘what is meant’ by an utterance. Therefore, in the above example, the knowledge that the question-like statement was ‘meant’ as a command in the given context can help in establishing the relation of this utterance with its accompanying behaviours, both by the speaker as well as by the listener. Hence the pragmatic meaning rather than the semantic content of speech may be crucial in understanding the phenomenon of verbal mediation of behaviour.

Such a discursive and pragmatic approach to classifying speech originates from the theory of speech acts proposed by Austin (1962) and Searle (1969). According to Austin (1962), a locution refers to ‘what was said’ in an utterance, while an illocution refers to ‘what was meant’ by the

speaker, while the effect of the illocution is termed as perlocution. Thus, an illocutionary act or speech act can be defined as an utterance which performs a certain ‘action’ through the act of speaking something with a particular intention of causing the action, in contrast to a linguistic act which only involves saying something meaningful in a language. Hence, we perform numerous actions such as - making claims, taking oaths, apologising, criticising, requesting and so on, simply by saying certain words. Intrinsic to a speech act is the intention of the speaker to produce a desired ‘action’ through its utterance. The intention with which a speech act is delivered was termed as the illocutionary force by Searle (1969). Only by attending to both the linguistic features of the utterance as well as it illocutionary force, can the listener fully comprehend and recognise a speech act. The response that the listener makes to the speech act as an effect of the illocutionary force was defined as the perlocutionary effect. Several researchers have since used the concept of speech acts in categorising utterances on the basis of the intended meaning (i.e., illocutionary force) and effect of an utterance (i.e., perlocutionary effect) spoken in a given context (Bruner, 1975; Dore, 1977; Feigenbaum, 1992; Furrow, 1984; Grice, 1975; Searle, 1979). Some of these categories suggested by Searle (1979) are as follows: assertives (utterances through which the speaker intends to assert the truth of a proposition, e.g. claiming, insisting, swearing, deducing, boasting, etc.), directives (utterances through which the speaker wants the listener to do something, e.g., asking, begging, requesting, suggesting, commanding, inviting, pleading), commissives (utterances through which the speaker commits to a future course of action, e.g., promising, pledging, proposing, etc.), expressives (utterances through which one’s emotional and affective state in a certain condition is expressed, e.g., apologising, congratulating, thanking, deploring, commiserating, welcoming, etc.) Since speech acts are necessarily embedded in the particular culture and context in which they are used, there is no consensus on the exhaustive list of all categories of speech acts that are used in any particular language. Hence classification systems vary in their particular set of categories, depending on the focus of the study itself.

2.5.3.4 Confusion between form, content and function of speech

Private speech studies have usually employed more than one dimension of speech in classifying their speech utterances. While in some cases, two or more dimensions of speech would be independently coded (Azmitia, 1992; Goudena, 1987; Kraft & Berk, 1998; Winsler, 1998; Winsler et al., 2003), many studies have combined these dimensions in one construct. One such example is the three-level coding system developed by Berk (1986), which is one of the most widely used typologies for private speech (Berk & Spuhl, 1995;Fernyhough & Fradley, 2005; Lidstone, Meins

& Fernyhough, 2010; Winsler, 1998; Winsler et al., 2003). Here, the degree of internalisation of private speech (dimension of form) has also come to include the concept of task-relevance (dimension of content). The content of those loud utterances, which are not related to the task that the child is engaged in, are termed as task-irrelevant (Level I), and are assumed to be the most immature form of private speech. Next in this proposed developmental hierarchy are the overt utterances which are related to the task, and are called task-relevant (Level II) private speech. The most mature level of private speech includes whisperings or lip movements, which are considered to be the external manifestations of inner speech (Level III). Although the content of the inaudible speech at Level III cannot be examined for task-relevance, it is assumed to be task-relevant, based on the assumption that it is the most mature form of private speech before it is completely internalised. Thus, the dimensions of form and content are assumed to be overlapping and synonymous.

The categories of task-relevant and task-irrelevant speech indicating content of private speech have also been assumed in some cases, as synonymous with ‘self-regulatory’ and ‘non self-regulatory’ private speech, respectively (Frauenglass & Diaz, 1985), thus inferring function from content. However, utterances such as word-play, repetition and affective expressions which may not appear to be goal-directed or even directly related to the task, may actually perform functions such as directing or sustaining attention during the task, or attributing responsibility for task failure to the external environment, thereby performing a task-relevant and self-regulatory role (Frawley & Lantolf, 1986). Assuming a priori that certain forms of speech have particular functions can lead to misleading conclusions about the role of private speech in verbal mediation of behaviour. Hence there have been persistent demands in the private speech literature to address the confusion between the form/content and function of private speech (Atencio & Montero, 2009; Diaz, 1986; Frawley & Lantolf, 1986; Matuga, 2003). By attributing inferred functional categories to the structural form or semantic content of private speech in coding schemes, several important studies (Berk & Spuhl, 1995; Fernyhough & Fradley, 2005; Frauenglass & Diaz, 1985) have failed to adequately differentiate between the various dimensions of children's private speech. Hence, more carefully constructed taxonomies which measure the various dimensions of speech independent from each other, as well as independent from any proposed function of speech need to be formulated, in deriving sound conclusions about the role, if any, of spontaneous speech in children's verbal mediation of behaviour. Researchers (Atencio & Montero, 2009; Diaz, 1986, 1999; Matuga, 2003) have also suggested the use of behavioural measures which are independent from the speech

measures, in order to examine their association with different categories of speech.