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D J Lewkowicz

Publications and source records attributed to D J Lewkowicz.

12 recordsLinked to original sources
PubMed2000

The development of intersensory temporal perception: an epigenetic systems/limitations view.

Several theories have stressed the importance of intersensory integration for development but have not identified specific underlying integration mechanisms. The author reviews and synthesizes current knowledge about the development of intersensory temporal perception and offers a theoretical model based on epigenetic systems theory, proposing that responsiveness to 4 basic features of multimodal temporal experience--temporal synchrony, duration, temporal rate, and rhythm--emerges in a sequential, hierarchical fashion. The model postulates that initial developmental limitations make intersensory synchrony the basis for the integration of intersensory temporal relations and that the emergence of responsiveness to the other, increasingly more complex, temporal relations occurs in a hierarchical, sequential fashion by building on the previously acquired intersensory temporal processing skills.

Adult↗
PubMed1998

Infants' response to the audible and visible properties of the human face: II. Discrimination of differences between singing and adult-directed speech.

Human infants' responsiveness to the audible and visible features of human faces was studied by habituating them to a person speaking a prepared script in an adult-directed manner and then administering a series of separate test trials where a person could be seen, heard, or seen and heard singing. When habituated to a female person speaking in an adult-directed manner and tested with a singing female 4, 6, and 8-month-old infants responded to the audible, visible, and bimodal changes, whereas 3-month-old infants only responded to the visual and bimodal changes. In contrast, when habituated to a male person speaking in an adult-directed manner and tested with a singing female, all age groups discriminated all three types of changes. These findings demonstrate that infants are responsive to differences between low- and high-prosody content inherent in both the facial and vocal characteristics of the human face and that, whereas responsiveness to the visible and bimodal features associated with differences between adult-directed speech and singing is present as early as 3 months of age, responsiveness to the audible features emerges between 3 and 4 months of age depending on whether gender differences are present as well.

Acoustic Stimulation↗
PubMed1996

Intersensory experience and early perceptual development: the role of spatial contiguity in Bobwhite quail chicks' responsiveness to multimodal maternal cues.

In contrast to the large body of work on young infants' capacity to perceive temporally based intersensory relations, little research has been done on the role of spatial contiguity in the development of audio-visual integration. This study examined the effects of early postnatal sensory experience on an avian neonate's responsiveness to the spatial contiguity between maternal auditory and visual cues. Specifically, we assessed whether a bobwhite quail chick's ability to respond to the correspondence between the location of auditory and visual events is affected by its sensory-stimulation history. Results revealed that chicks denied species-typical auditory or visual experience in the period immediately following hatching showed altered patterns of responsiveness to maternal auditory and visual cues. In particular, chicks that received modified postnatal sensory experience demonstrated a higher tolerance for audio-visual spatial discrepancy than did control chicks. These results provide evidence of the important role of sensory experience in the emergence of intersensory integration during the perinatal period and highlight the role of spatial information in early perceptual responsiveness to maternal cues.

Aging↗
PubMed1996

Perception of auditory-visual temporal synchrony in human infants.

Using a habituation/test procedure, the author investigated adults' and infants' perception of auditory-visual temporal synchrony. Participants were familiarized with a bouncing green disk and a sound that occurred each time the disk bounced. Then, they were given a series of asynchrony test trials where the sound occurred either before or after the disk bounced. The magnitude of the auditory-visual temporal asynchrony threshold differed markedly in adults and infants. The threshold for the detection of asynchrony created by a sound preceding a visible event was 65 ms in adults and 350 ms in infants and for the detection of asynchrony created by a sound following a visible event was 112 ms in adults and 450 ms in infants. Also, infants did not respond to asynchronies that exceeded intervals that yielded reliable discrimination. Infants' perception of auditory-visual temporal unity is guided by a synchrony and an asynchrony window, both of which become narrower in development.

Adolescent↗
PubMed1992

Infants' responsiveness to the auditory and visual attributes of a sounding/moving stimulus.

Responses to unimodal and multimodal attributes of a compound auditory/visual stimulus were investigated in 4-, 6-, 8-, and 10-month-old infants. First, infants were habituated to a compound stimulus consisting of a visual stimulus that moved up and down on a video monitor and a sound that occurred each time the visual stimulus reversed direction at the bottom. Once each infant met a habituation criterion, a series of test trials was administered to assess responsiveness to the components of the compound stimulus. Response was defined as the total duration of visual fixation in each trial. In the two unimodal test trials, the rate at which the component was presented was changed while the rate of the other component remained the same, whereas in the bimodal test trial the rate of both components was changed simultaneously. Results indicated that infants at each age successfully discriminated the bimodal and the two unimodal changes and that regression to the mean did not account for the results. Results also showed that disruption of the temporal relationship that accompanied the change in rate in the two unimodal test trials was also discriminable, but rate changes appeared to play a greater role in responsiveness than did synchrony changes. Considered together with results from similar prior studies, the current results are consistent with the modality appropriateness hypothesis in showing that discrimination of temporal changes in the auditory and visual modalities is dependent on the specialization of the sensory modalities.

Arousal↗
PubMed1990

Handling preterm infants in hospitals. Stimulating controversy about timing of stimulation.

The authors' research draws from a primary concern for the effects of the animate and inanimate caregiving environment on brain growth and central nervous system organization in hospitalized preterm infants. The current report presents data on physiologic trends in preterm infant heart rate and oxygenation as related to the timing and content of caregiver stimulation, specifically medical and social forms of touch. Results indicate that while most instances of bradycardia were not closely preceded by tactile stimulation, prebradycardia periods, which included touch, had lower pO2 levels than did baseline periods that included touch. These findings suggest that medical or "developmental" tactile stimulation presented when the infant was already physiologically compromised (with low pO2) may potentiate an underlying vulnerability to bradycardia. Timing, versus type, may be the better predictor of the physiologic effect of caregiver interventions on preterm infants.

Heart Rate↗
PubMed1987

Advances in neonatal and infant behavioral assessment: toward a comprehensive evaluation of early patterns of development.

Recognizing the impressive range of behavioral capacities of newborn infants, clinicians and researchers have long searched for valid assessment instruments to help evaluate infant behavior. Behavioral assessments with high predictive validity would aid the goals of developmental diagnostic, prognostic, and treatment programs for infants born at risk from biological or environmental circumstances. The failure of current assessments to predict developmental outcome based on infant behavior may be due to the limited information about higher central nervous system (CNS) functioning obtained from available measures, or to the very dynamic nature of CNS organization in young infants. We begin our review by discussing some major functional characteristics of neonates and then proceed to describe critically the commonly used methods of neurological and behavioral assessment. Noting the need for measures that are more predictive, we turn next to a discussion of a number of experimental techniques that seem to hold great promise for developmental prediction and clinical application.

Child Behavior↗
PubMed1981

Intersensory interaction in newborns: modification of visual preferences following exposure to sound.

The present study investigated intersensory interaction between auditory and visual stimulation in newborn infants. Stimulation in 1 modality may influence the response to stimulation in a second modality by changing the infant's state of arousal. To test this possibility, newborns' visual preferences for light patches of different intensity were examined following auditory stimulation. Visual preferences in infants not previously exposed to sound described an inverted U, indicating a preference for the light of intermediate intensity. In contrast, infants who were first exposed to sound preferred the light or lowest intensity. The results indicate that newborns attend to quantitative variations in stimulation and that these variations reflect both the objective stimulus intensity and organismic factors.

Arousal↗
PubMedDate not supplied

Infants' perception of the audible, visible, and bimodal attributes of multimodal syllables.

Three experiments investigated 4-, 6-, and 8-month-old infants' perception of the audible, visible, and combined attributes of bimodally specified syllables. Ninety-six infants in each experiment were habituated to a person mouthing and uttering a syllable and then tested for detection of changes of either the audible, visible, or combined attributes of the syllable. When the attributes of the syllable were produced in an adult-directed manner, all three age groups discriminated the audible and bimodal attribute changes but only the 8-month-olds discriminated the visible one. When the difference between the familiar and novel attributes of the syllable was enhanced by testing with a novel syllable produced in an infant-directed manner, all three age groups detected all three types of changes. Finally, to test the possible role of audiovisual synchrony in responsiveness, infants were tested with an asynchronous syllable spoken either by the same person or by a novel person following habituation to a synchronous syllable. Results suggested that at four months infants attended primarily to the featural information, at six months primarily to the asynchrony, and at eight months to both features independently. These results help identify some of the important dimensions of multimodal speech during early development.

Age Factors↗