Joseph Jaffe

Vocalizing in unison and in alternation: two modes of communication within the mother-infant dyad.

Two laboratories studying dyadic communication have joined in a n ongoing research project on the ontogeny of communication. One laboratory has engaged in the study of naturally occurring interactions between mothers and infants, particularly their “nonverbal” communication.’-6 The other has focused on the rhythm of adult Together, we are examining vocal and kinesic behaviors and their integration during the course of development. This paper presents a part of that ongoing study. During the first half-year of life the infant communicates effectively through a variety of behaviors: head and body movement and tone, gaze, facial expressions, and vocalizations. By the age of three to four months, all of these behaviors can be integrated to form recognizable complex expressive acts. The distinction between vocal and other motor acts is less compelling at this point in development, and in fact, if made too sharply, may obscure a view of early vocalization. For instance, when watching a film of an infant, with the sound turned off, it is impossible to predict reliably when he is vocalizing. In social situations, there exists a wide range and variety of mouth behaviors, especially mouth-opening with head thrown up, which are extremely expressive and evocative.4 These may or may not be accompanied by a vocalization. When a vocalization is added to the entire kinesic event, that event becomes importantly different. Nonetheless, infant vocalizations rarely occur (in a social situation) as an isolated motor act such as an adult can perform in speaking; rather, they occur as another element in the constellation of kinesic events that make up a communicative act. Furthermore, they occur within an interpersonal context in which the levels of arousal and affective tone are constantly changing. We thus have examined mother and infant vocalization from the viewpoint that they are sound-producing kinesic events, as well as prelinguistic events which later transform into speech. This paper was initially prompted by an unexpected finding. During play sessions, mothers and their threeto four-month-old infants vocalize simultaneously to a far greater extent than we had anticipated or than had been commented on in the literature. Early vocalizations appear to have at least one beginning within the motherinfant dyad as a coaction system in which each member is performing the same or similar behavior a t the same time. This occurrence of behavioral coaction between

“Conversational” coupling of gaze behavior in prelinguistic human development

Mathematical regularities in the gross temporal pattern of infant-adult gaze behavior are identical to those found in adult verbal conversations. Both types of interaction conform to a Markov chain model. Such regularities suggest some universal property of human communication which predates the onset of speech. The present infants were 3.5 months old.

Infant gaze, head, face and self-touch at 4 months differentiate secure vs. avoidant attachment at 1 year: A microanalytic approach

The study attempted to distinguish avoidant vs. secure infants at 1 year from 4-month infant behavior only, during a face-to-face play interaction with the mother. Thirty-five 4-month-old infants were coded second by second for infant gaze, head orientation, facial expression and self-touch/mouthing behavior. Mother behavior was not coded. At 1 year, 27 of these infants were classified as secure (B), and 8 as avoidant (A) attachment in the Ainsworth Strange Situation. Compared with the B infant, the future A infant spent less time paying ‘focused’ visual attention (a look of a minimum 2 seconds duration) to the mothers face. Only if the A infant engaged in self-touch/mouthing behavior did its focused visual attention match that of the B. Markovian t to t+1 transition matrices then showed that both for future A and for future B infants, focused visual attention on the mother constrained the movements of the head to within 60 degrees from center vis-à-vis, defining head/gaze co-ordination within an attentional-interpersonal space. However, infant maintenance of head/gaze co-ordination was associated with self-touch/mouthing behavior for the A infant but not the B. Positive affect was associated with a disruption of head/gaze co-ordination for the A but not the B. Whereas the B had more variable facial behavior, potentially providing more facial signaling for the mother, the A had more variable tactile/mouthing behavior, changing patterns of self-soothing more often. Thus, infants classified as A vs. B at 12 months showed different behavioral patterns in face-to-face play with their mothers as early as 4 months.

Six-Week Postpartum Maternal Self-Criticism and Dependency and 4-Month Mother-Infant Self- and Interactive Contingencies.

Associations of 6-week postpartum maternal self-criticism and dependency with 4-month mother-infant self- and interactive contingencies during face-to-face play were investigated in 126 dyads. Infant and mother face, gaze, touch, and vocal quality were coded second by second from split-screen videotape. Self- and interactive contingencies were defined as auto- and lagged cross-correlation, respectively, using multilevel time-series models. Statistical significance was defined as p<.05. Regarding self-contingency, (a) more self-critical mothers showed primarily lowered self-contingency, whereas their infants showed both lowered and heightened, and (b) infants of more dependent mothers showed primarily lowered self-contingency, whereas findings were absent in mothers. Regarding interactive contingency, (a) more self-critical mothers showed lowered attention and emotion contingencies but heightened contingent touch coordination with infant touch, and (b) more dependent mothers and their infants showed heightened facial/vocal interactive contingencies. Thus, maternal self-criticism and dependency have different effects on mother-infant communication.

Coordinated interpersonal timing in adult-infant vocal interactions: A cross-site replication**

Coordinated interpersonal tinning exists when the temporal pattern of each partner in a dialogue is predictable from that of the other. Using a completely automated microanalytic technique to time the sequence of vocal sounds and silences in an interaction, we studied 28 four-month-old infants in face-to-face play with mother and a female stranger. Fifteen infants were recorded on one site and 13 at another. Time-series regression was used to evaluate the direction and magnitude of interpersonal prediction. Results indicated that (a) significant coordination (or its absence) occurred at both sites for 90% of the comparisons, and (b) the lag that best predicted the partner was 20 to 30 s at both sites. Unlike the labor-intensive microanalytic coding techniques that have dominated mother-infant interaction research, this work has the following advantages: (a) the automated instrumentation times behavior with a precision unobtainable by the unaided human observer; (b) the sound-silence variables are unambiguously defined for computer processing; and (c) the microanalytic method is applicable to large-sample studies. This automated method has shown its clinical utility in its power to predict 1-year developmental outcomes from 4-month coordinated interpersonal timing.

MARKOVIAN MODEL OF TIME PATTERNS OF SPEECH.

The time pattern of speech is describable as a first-order Markov process when presence or absence is sampled at a rate of 200 times per minute. Two types of monolog were generated under different conditions of environmental constraint. Although both fit the model, estimates of their mean range of statistical dependency differed significantly.

The Effect of Subject Sex, Verbal Interaction and Topical Focus on Speech Disruption

Forty-eight men and forty-eight women participated in four consecutive 5 minute subinterviews, two of which were concerned with personal problem content and two which were concerned with non-problem topics. in one problem and one non-problem subinterview the subject and experimenter engaged in naturalistic verbal interaction; in the other problem and non-problem subinterviews the talking was done only by the subject. The obtained speech samples were scored for proportions of Ah (filled pauses) and non-Ah speech disturbances. Statistical analysis indicated that the Ah ratio differentiated the sex groups although the non-Ah ratio did not. Higher non-Ah ratios were elicited by the interactive and problem subinterviews than by the non-interactive and non-problem subinterviews and there was a significant interaction effect. The male group emitted higher proportions of filled pauses in the interactive and problem subinterviews while the female group emitted higher proportions only in the interactive subinterviews and was not differentially affected by the problem and non-problem subinterviews. A post hoc analysis of verbal rate revealed that, like the non-Ah ratio, it differentiates interactive and non-interactive and problem and non-problem sub-interviews and shows a significant interaction effect. in addition, comparisons were made of the dependent variables with age, educational level, and a brief estimate of verbal intelligence.

Timing Analysis of Coding and Articulation Processes in Dyslexia

Several investigators have found that the time required to perform serial naming tasks is a good predictor of dyslexia in children. Protracted overall time scores, such as are reported for the Rapid Automatized Naming (RAN) test of Denckla and Rudel, are, by themselves, insufficient to determine the extent to which the performance deficit is cognitive in nature, or is the articulatory consequence of an inability master the quickly changing acoustic formant patterns associated with consonants, as proposed by Tallal. We administered the RAN test to matched groups of dyslexic and normal control children, aged 8 to 11 years. Measurement of speech signal durations was performed by computer. We applied the Gould and Boies algorithm for extracting cognitive preparation time to these data, resulting in a partition of overall RAN test score into coding time and articulation time components. Differential performances between the groups on RAN subtests were examined for effects of postvocalic consonants and semantic load. It was found that both vocalization time and pause time means were significantly longer for the dyslexics on each of the four RAN subtests: objects, colors, numbers, letters. The Gould and Boies analysis showed very little preparation time during speech in both groups, attributing virtually all coding time to pauses, although reanalysis suggested somewhat less. Increased vowel length among the dyslexics occurred on all subtests, but was not maximized on subtests with more numerous postvocalic consonants. Vowel time differences between groups accounted for nearly all of the differences in vocalization time. Profiles were constructed on speech measures which, for each subtest, correctly identified each subject with his group. On the letters subtest it was found that vowel duration alone achieved a perfect discrimination between the dyslexic and control subjects.

Coordinated Interpersonal Timing of Down-Syndrome and Nondelayed Infants with Their Mothers: Evidence for a Buffered Mechanism of Social Interaction

A longitudinal study of four- and nine-month-old infants indicates that they coordinate the timing of their vocal behavior with that of their mothers and vice versa. Maternal interactions of Down-syndrome and nondelayed infants were analyzed and found not to differ with regard to such temporal coordination, indicating that it is independent of level of cognitive functioning. The capacity for coordinated timing is proposed as a mechanism for the facilitation of social interaction. Such coordination parallels temporal matching observed in a variety of species along the phylogenetic scale.

Distressed Mothers and Their Infants Use a Less Efficient Timing Mechanism in Creating Expectancies of Each Other’s Looking Patterns

The prediction of events and the creation of expectancies about their time course is a crucial aspect of an infant’s mental life, but temporal mechanisms underlying these predictions are obscure. Scalar timing, in which the ratio of mean durations to their standard deviations is held constant, enables a person to use an estimate of the mean for its standard deviation. It is one efficient mechanism that may facilitate predictability and the creation of expectancies in mother–infant interaction. We illustrate this mechanism with the dyadic gaze rhythm of mother and infant looking at and looking away from each other’s faces. Two groups of Hi- and Lo-Distress mothers were created using self-reported depression, anxiety, self-criticism and childhood experiences. Lo-Distress infants (controls) used scalar timing 100% of the time, about double that of Hi-Distress infants. Lo-Distress mothers used scalar timing about nine times as much as Hi-Distress mothers. The diminished use of scalar timing patterns in Hi-Distress mothers and infants may make the anticipation of each other’s gaze patterns more difficult for both partners.