Premature visual stimulation accelerates intersensory functioning in bobwhite quail neonates

Recent evidence from both altricial and precocial neonates suggests that premature stimulation of a later developing sensory system may alter the functioning of earlier developing sensory systems. The present study examined the influence of prenatal visual stimulation on postnatal auditory functioning in precocial bobwhite quail chicks. Hatchlings that experienced patterned light during the 24-36 hr prior to hatching did not exhibit a naive auditory preference for their species-specific maternal call at 24 hr or 48 hr following hatching, a reliable phenomenon in chicks not receiving embryonic visual stimulation. To examine whether this lack of responsiveness resulted from enhanced intersensory functioning, hatchlings were tested for preference for both auditory and visual features of the bobwhite hen. Results indicate that prematurely stimulated chicks require species-typical auditory and visual stimulation earlier in postnatal development than do normally reared chicks to direct their filial behavior. These findings point to the importance of normally occurring developmental limitation of sensory input to early species-typical sensory/perceptual organization.     

Augmented prenatal tactile and vestibular stimulation alters postnatal auditory and visual responsiveness in bobwhite quail chicks.

The fact that the sensory systems do not become functional at the same time during early development raises the question of how sensory systems and their respective stimulative histories might influence one another. Previous studies have shown that unusually early visual experience can alter subsequent responsiveness of both the visual system and the earlier developing olfactory and auditory systems. The question remains as to the extent which modified stimulation to an earlier developing system can also result in changes in responsiveness in later developing sensory systems. This study examined the effects of augmented prenatal tactile and vestibular stimulation on bobwhite quail chicks' postnatal visual and auditory responsiveness to maternal cues. Results indicate that augmented prenatal tactile and vestibular stimulation can alter postnatal perceptual responsivensss in the later developing auditory and visual sensory systems. Chicks exposed to augmented prenatal proximal stimulation continued to respond to maternal auditory cues into later stages of postnatal development and failed to demonstrate responsiveness to maternal visual cues in the days following hatching. However, augmented tactile and vestibular stimulation did not appear to affect prenatal auditory learning of an individual maternal call. These findings indicate a strong but selective pattern of influence between the sensory modalities during the prenatal period and support the view that substantially increased amounts of prenatal sensory stimulation can interfere with the emergence of species-typical perceptual functioning.     

Augmented prenatal visual stimulation alters postnatal auditory and visual responsiveness in bobwhite quail chicks

This study examined whether previously reported effects of altered prenatal sensory experience on subsequent acceleration of intersensory development in precocial birds are mediated by mechanisms sensitive to the overall amount of stimulation provided. Results revealed that bobwhite quail chicks exposed to substantially augmented amounts of prenatal visual stimulation show altered patterns of species-typical perceptual development. Specifically, chicks continued to respond to maternal auditory cues into later stages of postnatal development and failed to demonstrate responsiveness to maternal visual cues. Embryos also failed to demonstrate prenatal auditory learning of an individual maternal call, a behavior reliably seen in unmanipulated embryos. These findings suggest that substantially increased amounts of prenatal sensory stimulation can interfere with the emergence of species-typical patterns of postnatal intersensory functioning and lend support to the notion that sensory stimulation that falls within some optimal range maintains or facilitates normal patterns of perceptual development, whereas stimulation beyond the range of the species norm can result in intersensory interference. © 1995 John Wiley & Sons, Inc.     

Specific postnatal auditory stimulation interferes with species-typical visual responsiveness in bobwhite quail chicks

The effects that a manipulation of sensory experience may have on perceptual development are likely to depend on a number of factors, including the amount and the type of stimulation provided. To examine the relative influence of these stimulation factors on early perceptual organization, this study exposed bobwhite quail hatchlings to augmented amounts of bobwhite chick distress calls, bobwhite chick contentment calls, domestic chicken distress calls, or no additional auditory stimulation during the first 72 hr following hatching. Results showed that bobwhite hatchlings exposed to bobwhite chick distress calls do not exhibit species-typical visual responsiveness to maternal cues. In contrast, bobwhite hatchlings exposed to bobwhite chick contentment calls, domestic chicken hatchling distress calls, or no agumented auditory stimulation exhibited species-typical auditory and visual responsiveness to maternal cues. These results demonstrate intermodal effects of postnatal sensory stimulation and suggest that specific types of postnatal auditory stimulation, rather than simply increased amount of stimulation, are necessary to interfere with species-typical intersensory functioning.© 1994 John Wiley & Sons, Inc.     

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 temporarilly 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. © 1996 John Wiley & Sons, Inc.     

Augmented prenatal auditory stimulation alters postnatal perception,arousal, and survival in bobwhite quail chicks

This study examined whether previously reported effects of altered prenatal sensory experience on subsequent acceleration of intersensory development in precocial birds are mediated by mechanisms sensitive to the overall amount of stimulation provided. Results revealed that bobwhite quail chicks exposed to substantially augmented amounts of prenatal auditory stimulation show altered patterns of species-typical perceptual development. Specifically, chicks continued to respond to maternal auditory cues into later stages of postnatal development and failed to demonstrate responsiveness to maternal visual cues. In addition, embryos exposed to substantially augmented amounts of prenatal auditory stimulation exhibited a higher level of behavioral arousal and higher mortality rates than embryos provided either moderately augmented amounts or no additional amount of prenatal auditory stimulation. These findings suggest that substantially increased amounts of prenatal sensory stimulation can interfere with the emergence of species-typical patterns of postnatal perceptual functioning and lend support to the notion that sensory stimulation that falls within some optimal range maintains or facilitates normal patterns of perceptual development, whereas stimulation beyond the range of the species norm can result in intrasensory and intersensory interference. © 1997 John Wiley & Sons, Inc. Dev Psychobiol 30: 201–212, 1997     

Contextual determinants of auditory learning in bobwhite quail embryos and hatchlings.

This study examined the ability of bobwhite quail embryos and hatchlings to learn an individual bobwhite maternal call. Results revealed that embryos could learn an individual maternal call and remember that call for at least 24 hr following exposure. In contrast, hatchlings reared socially in groups of same-age chicks during postnatal exposure to a maternal call did not demonstrate a preference for that familiar call at 24 hr following exposure. However, individual auditory recognition was exhibited by hatchlings reared in social isolation, suggesting that the perceptual and social complexity of the postnatal situation can disrupt or interfere with early auditory learning. Additional support for this view was the finding that embryos exposed to unusually early visual stimulation during prenatal exposure to a maternal call also failed to prefer that familiar maternal call in subsequent choice tests. The idea that early auditory learning capacity is determined more by context and experience rather than the organism's specific age or stage of development is discussed.     

Prenatal exposure to temporal and spatial stimulus properties affects postnatal responsiveness to spatial contiguity in bobwhite quail chicks

Little is known about how experiential factors guide and organize the development of intersensory perception. This study manipulated the amount of late prenatal and early postnatal experience with the temporal synchrony and spatial contiguity of audio-visual stimulation available to bobwhite quail embryos and hatchlings to explore this question. Results revealed that only embryos exposed to temporally synchronous and spatially contiguous audio-visual stimulation prior to hatching subsequently preferred spatially contiguous audio-visual maternal information following hatching, despite being denied postnatal visual experience. In contrast, embryos that did not receive exposure to both temporal synchrony and spatial contiguity (and were also denied postnatal visual experience) failed to show a preference for the spatial contiguity of maternal auditory and visual information following hatching. These results suggest that prenatal exposure to the amodal properties of temporal synchrony and spatial contiguity facilitate chicks' emerging sensitivity to the spatial contiguity of audio-visual information in the period following hatching.     

Development of visually controlled maternal preferences in Peking ducklings

The interaction between natural visual and auditory stimulation in the control of filial behavior was studied in domestic mallard (Peking) ducklings during the first 3 days of postnatal life. Visual imprinting at 24 hr resulted in a visual preference for the familiar model over an unfamiliar model in each of two choice tests, one at 48 hr and one at 72 hr, but only if both models were silent. If both models emitted a recording of the mallard maternal call, the visual preference was found only in the later (72-hr) test. Visuomotor experience between training and testing was found to be essential for the development of the visual preference at 72 hr, but the required experience was of a very general nature. Either a choice test with silent models or a period of social rearing (between 24 and 72 hr) provided effective experience. Thus, the ability to show a visual preference in the presence of the maternal call at 72 hr depends on experience, but not necessarily on further exposure to the imprinting object or to any specific aspects of the test situation. These results demonstrate the importance of normal visual, motor and/or social experience to the development of the visual control of filial behavior in ducklings.     

Biased embryos: Prenatal experience alters the postnatal malleability of auditory preferences in bobwhite quail

Many precocial birds show a robust preference for the maternal call of their own species before and after hatching. This differential responsiveness to species-specific auditory stimuli by embryos and neonates has been the subject of study for more than four decades, but much remains unknown about the dynamics of this ability. Gottlieb [Gottlieb [1971]. Development of species identification in birds: An enquiry into the prenatal determinants of perception. Chicago/London: University of Chicago Press.] demonstrated that prenatal exposure to embryonic vocalizations serves to canalize the formation of species-specific preferences in ducklings. Apart from this, little is known about the features of the developmental system that serve to canalize such species-typical preferences, on the one hand, and generate novel behavioral phenotypes, on the other. In the current study, we show that briefly exposing bobwhite quail embryos to a heterospecific Japanese quail (JQ) maternal call significantly enhanced their acquisition of a preference for that call when chicks were provided with subsequent postnatal exposure to the same call. This was true whether postnatal exposure involved playback of the maternal call contingent upon chick contact vocalizations or yoked, non-contingent exposure to the call. Chicks that received both passive prenatal and contingent postnatal exposure to the JQ maternal call redirected their species-typical auditory preference, showing a significant preference for JQ call over the call of their own species. In contrast, chicks receiving only prenatal or only postnatal exposure to the JQ call did not show this redirection of their auditory preference. Our results indicate that prenatal sensory stimulation can significantly bias postnatal responsiveness to social stimuli, thereby altering the course of early learning and memory.     

The influence of prenatal tactile and vestibular stimulation on auditory and visual responsiveness in bobwhite quail: A matter of timing

The fact that the sensory systems do not become functional at the same time during prenatal development raises the question of how experience in a given modality can influence functioning in other sensory modalities. The present study exposed groups of bobwhite quail embryos to augmented tactile and vestibular stimulation at times that either coincided with or followed the period of onset of function in the later-developing auditory and visual modalities. Differences in the timing of augmented prenatal stimulation led to different patterns of subsequent auditory and visual responsiveness following hatching. No effect on normal visual responsiveness to species-typical maternal cues was found when exposure to tactile and vestibular stimulation coincided with the emergence of visual function (Days 14-19), but when exposure took place after the onset of visual functioning (Days 17-22), chicks displayed enhanced responsiveness to the same maternal visual cues. When augmented tactile and vestibular stimulation coincided with the onset of auditory function (Days 9-14), embryos subsequently failed to learn a species-typical maternal call prior to hatching. However, when given exposure to the same type and amount of augmented stimulation following the onset of auditory function (Days 14-19), embryos did learn the maternal call. These findings demonstrate that augmented stimulation to earlier-emerging sensory modalities can either facilitate or interfere with perceptual responsiveness in later-developing modalities, depending on when that stimulation takes place.     

Order-dependent timing of unimodal and multimodal stimulation affects prenatal auditory learning in bobwhite quail embryos

This study examined the relationship between unimodal and multimodal sensory stimulation and their effects on prenatal auditory learning in bobwhite quail embryos. Embryos exposed to a maternal call in the 24 hr prior to hatching (unimodal condition) significantly preferred this familiar call over an unfamiliar call in postnatal testing, but failed to demonstrate this preference when the maternal call was presented concurrently with non-synchronized patterned light (multimodal condition). To further explore this interference effect, we provided one group of embryos concurrent exposure to a maternal call and patterned light for 12 hr followed by 12 hr exposure to the call alone (multimodal-->unimodal call). This group failed to prefer the familiar call during postnatal testing. In contrast, reversing the order of presentation during prenatal exposure (unimodal call-->multimodal) led a second group of subjects to significantly prefer the familiar call, suggesting that the order-dependent timing of sensory stimulation can significantly impact prenatal auditory learning. Experiment 3 examined the influence of modality versus timing of sensory stimulation on prenatal auditory learning by providing three groups of embryos with exposure to a maternal call during the 12 hr prior to hatching and by varying the duration of visual stimulation. Results indicate that 12 hr unimodal exposure to patterned light does not support prenatal auditory learning when it is followed by 12 hr exposure to multimodal stimulation (light-->multimodal), but can facilitate prenatal auditory learning when it is followed by unimodal exposure to the call alone (light-->call). Results are discussed in terms of intersensory relationships during perinatal development.     

Effects of early and delayed visual experience on intersensory development in bobwhite quail chicks

The relative impact of early versus delayed visual experience on intersensory development was studied by manipulating the timing of visual experience of bobwhite quail (Colinus virginianus) embryos and hatchlings. Previous studies with quail chicks have revealed that: (1) Socially reared chicks require only maternal auditory cues to direct their social preferences in the first 2 days following hatching; (2) by 3 days following hatching chicks require both auditory and visual maternal cues to direct their social preferences; (3) chicks which have received unusually early visual experience as embryos require both auditory and visual cues by 24 hr following hatching, indicating an accelerated pattern of the emergence of intersensory functioning; and (4) chicks reared under conditions of attenuated social and visual experience continue to rely on matenal auditory cues alone at 4 days following hatching, indicating a decelerated pattern of early intersensory functioning. In the present study, quail chicks that received both early visual experience as embryos and delayed visual experience as hatchlings exhibited a pattern of both auditory and visual responsiveness like that seen in normally reared chicks. These results indicate that, at least under the present experimental conditions, the influence of early and delayed visual experience on perinatal perceptual development appears to be relatively comparable in effect © 1993 John Wiley & Sons, Inc.     

Effects of redundant and nonredundant bimodal sensory stimulation on heart rate in bobwhite quail embryos

Research with both animal embryos and human infants has provided evidence that information presented redundantly and in temporal synchrony across sensory modalities (intersensory redundancy) can guide selective attention, perceptual learning, and memory during early development. How this facilitation is achieved remains relatively unexamined. This study examined the effects of redundant versus nonredundant bimodal stimulation on a measure of physiological arousal (heart rate) in bobwhite quail embryos. Results show that quail embryos exposed to concurrent but nonredundant auditory and visual stimulation during the late stages of incubation exhibit significantly elevated heart rates following stimulus exposure and during stimulus reexposure when compared to embryos exposed to redundant and synchronous audiovisual stimulation, unimodal auditory stimulation, or no supplemental prenatal sensory stimulation. These findings indicate a functional distinction between redundant and nonredundant bimodal stimulation during early development and suggest that nonredundant bimodal stimulation during the prenatal period can raise arousal levels, thereby potentially interfering with the attentional capacities and perceptual learning of bobwhite quail. In contrast, intersensory redundancy appears to foster arousal levels that facilitate selective attention and perceptual learning during prenatal development.     

Effects of prenatal sensory stimulation on heart rate and behavioral measures of arousal in bobwhite quail embryos

Although a number of studies have demonstrated the effects of altered prenatal experience on subsequent behavioral development, how these effects are achieved remains a topic of enduring interest. The present study examined the immediate effects of unimodal and multimodal prenatal sensory stimulation on physiological and behavioral arousal in bobwhite quail embryos. Embryos were videotaped and their heart rate was monitored during a 4-min exposure period to (a) no supplemental sensory stimulation, (b) unimodal auditory stimulation, (c) unimodal visual stimulation, (d) two sources of concurrent auditory stimulation, or (e) concurrent auditory/visual stimulation. Results indicated that quail embryos' overall activity levels and heart rate can be significantly affected by the type of prenatal sensory stimulation provided during the period prior to hatching. In particular, multimodal stimulation increased both behavioral activity levels and heart rate compared to controls. Across the unimodal and intramodal groups, however, behavioral and physiological measures revealed different patterns of activity in response to supplemental sensory stimulation, highlighting the value of using multiple levels of analysis in exploring arousal mechanisms involved in prenatal perceptual responsiveness.     

Maternally separated rats show deficits in maternal care in adulthood

Although there is considerable research on the phenomenology, neuroendocrinology, neuroanatomy, and sensory control of maternal behavior, little is known about the influences of early postnatal and postweaning experiences on the development of maternal behavior. The purpose of this study was to assess how early life separation from the mother rat affects development of the offspring's juvenile and adult maternal behavior. From postnatal Days 1 to 17, 3 female rats within each litter were separated (SEP) from the mother and the rest of the litter for 5 hr daily while 3 of their sisters were not maternally separated (NSEP). On postnatal Day 21, all subjects were weaned and randomly assigned to one of three juvenile conditions. One female from both SEP and NSEP groups was either isolated (I), given a social conspecific (S), or given 1- to 4-day-old pups (P) for 5 consecutive days. Maternal behavior of SEP and NSEP animals was assessed and recorded on each of the 5 days. Once all animals reached adulthood, they were mated, gave birth, and were assessed for their maternal behavior. We found that the effects of maternal separation on juvenile maternal-like behaviors were minimal. On the other hand, maternal separation reduced adult maternal licking and crouching over pups. In addition, there was a significant interaction between postnatal and juvenile experience on maternal crouching in maternal animals. These results are discussed in terms of the variety of possible behavioral, endocrine, and neurochemical mechanisms that mediate the effects of early life experiences on adult maternal behavior.     

Early postnatal deprivation of active sleep with desipramine or zimeldine impairs later behavioural reactivity to auditory stimuli in rats

To examine the functional significance of early postnatal active sleep for the development of behavioural reactivity to auditory stimuli, rat pups were daily injected i.p. from the 7th to the 18th postnatal days with 5 mg kg-1 (6.6 mmol l-1) desipramine or 25 mg kg-1 (12.2 mmol l-1) zimeldine. Sleep-wake behaviour was recorded with a static-charge-sensitive bed (SCSB) method. Both desipramine and zimeldine suppressed the percentage of active sleep relative to the total recording time throughout the treatment period. In addition, these drugs increased the percentage of quiet state and waking. At the age of 38 days the zimeldine-treated rats showed more motor activity in the open field than the controls. At the age of 39 and 78 days all rat groups behaved similarly in the open field. Startle measures and motor activation, provoked by auditory stimulation, were determined by the SCSB method when the rats were 4 months of age. Auditory stimuli, consisting of a series of ten clicks, induced a greater number of startles as well as strong movement responses in the control rats than in the desipramine- or zimeldine-treated rats. The number of small movement responses did not differ between the rat groups. These findings indicate that early postnatal active sleep and the monoaminergic systems regulating it may be important for the normal development of neuronal circuitry associated with later reactivity to auditory stimuli.     

Ontogeny of eyeblink conditioning using a visual conditional stimulus

The developmental emergence of associative learning in rodents is determined by interactions among sensory, motor, and associative systems that are engaged in a particular experimental preparation (Carter & Stanton, 1996; Hunt & Campbell, 1997; Rudy, 1992). In fear conditioning, chemosensory, auditory, and visual cues emerge successively as effective conditional stimuli (CS) during postnatal ontogeny. In the present study, we begin to examine the generality of this principle of sensory system development for eyeblink conditioning, a form of associative learning that develops substantially later than conditioned fear (Carter & Stanton, 1996). We asked whether the developmental emergence of eyeblink conditioning to a visual CS occurs at an age that is the same or different from conditioning to an auditory CS. In Experiment 1, rat pups were trained on postnatal Day 17 or 24 with experimental parameters (and design) that were identical to our previous studies of eyeblink conditioning except that presentation of a light rather than a tone served as the CS. The outcome was also identical: no eyeblink conditioning on Day 17 and strong conditioning on Day 24. In Experiment 2, conditioning to tone versus light was directly compared by means of a discrimination learning design on postnatal Days 19, 21, 23, and 31. There was no evidence for differential development of auditory versus visual eyeblink conditioning. The difference between this outcome and previous ones involving conditioned fear (Hunt & Campbell, 1997; Rudy, 1992) suggests that principles concerning sensory maturation and learning may be different for early- versus late-developing associative systems.     

Prenatal visual experience influences the development of turning bias in bobwhite quail chicks (Colinus virginianus)

This study examined the effects of prenatal sensory experience on the development of turning bias in a precocial avian species (bobwhite quail). Control tests with naive bobwhite quail chicks revealed a left-side turning bias in 85% of subjects. Such large population biases are considered unusual in nonhuman species. Experiments 1, 2, and 3 demonstrated that prenatal visual experience is a significant contributor to this population level left-side turning bias in bobwhite quail chicks. In contrast, prenatal auditory experience did not appear to significantly influence the development of postnatal turning bias. The findings of this study are discussed in terms of an epigenetic theory for the development of hemispheric specialization and behavioral asymmetry. © 1998 John Wiley & Sons, Inc. Dev Psychobiol 32: 327–338, 1998     

Development of motor activity in kittens

Developmental alterations in motor activity were quantified for the 1st 7 postnatal months in the kitten. Motor activity measured with a stabilimeter was low and constant for the 1st 9 postnatal days, increased markedly until Day 14, and remained stable until Day 21. Locomotor activity measured in an open field decreased slightly during the 1st 3 weeks, increased markedly during the next 2 weeks, and then remained relatively constant until the 9th week. Activity increased again during the 3rd and 4th month and then declined until 7 months of age. We suggest that the marked increase in motor activity during the 2nd week reflects development of visual and auditory systems whereas the increase in locomotor activity during the 4th and 5th weeks represents maturation of neural systems concerned with motor control. The underlying causes of the final activity changes probably represent the maturation of many neural systems and concomitant development of adult behavior in the cat.