The role of task difficulty in directing selective attention in bobwhite quail (Colinus virginianus) neonates: A developmental test of the intersensory redundancy hypothesis.

The dynamics of selective attention necessarily influences the course of early perceptual development. The intersensory redundancy hypothesis proposes that in early development information presented redundantly across two or more senses selectively recruits attention to the amodal properties of an object or event. In contrast, information presented to a single sense enhances attention to modality-specific properties. The present study assessed the second of these predictions in neonatal bobwhite quail (Colinus virginianus), with a focus on the role of task difficulty in directing selective attention. In Experiment 1, we exposed quail chicks to unimodal auditory, nonredundant audiovisual, or redundant audiovisual presentations of a bobwhite maternal call paired with a pulsing light for 10 min/h on the day following hatching. Chicks were subsequently individually tested 24 h later for their unimodal auditory preference between the familiarized maternal call and the same call with pitch altered by two steps. Chicks from all experimental groups preferred the familiarized maternal call over the altered maternal call. In Experiment 2, we repeated the exposure conditions of Experiment 1, but presented a more difficult task by narrowing the pitch range between the two maternal calls during testing. Chicks in the unimodal auditory and nonredundant audiovisual conditions preferred the familiarized call, whereas chicks in the redundant audiovisual exposure group showed no detection of the pitch change. Our results indicate that early discrimination of pitch change is disrupted by intersensory redundancy under difficult but not easy task conditions. These findings, along with findings from human infants, highlight the role of task difficulty in shifting attentional selectivity and underscore the dynamic nature of neonatal attentional salience hierarchies.

Development as explanation: Understanding phenotypic stability and variability after the failure of genetic determinism.

In the predominately gene-centered view of 20th century biology, the relationship between genotype and phenotype was essentially a relationship between cause and effect, between a plan and a product. Abandoning the idea of genes as inherited instructions or blueprints for phenotypes raises the question of how to best account for observed phenotypic stability and variability within and across generations of a population. We argue that the processes responsible for phenotypic stability and the processes responsible for phenotypic variability are one and the same, namely, the dynamics of development. This argument proposes that stability of phenotypic form is found not because of the transmission of genotypes, genetic programs, or the transfer of internal blueprints, but because similar internal and external conditions-collectively conceptualized as resources of development-can be reliably reconstituted in each generation. Variability of phenotypic form, which is an indispensable feature of any evolving system, relies on these same resources, but because the internal and external conditions of development are not reconstituted identically in succeeding generations, these conditions-and the phenotypes to which they give rise-will always be characterized by at least some variability.

How deep do we have to go to rehabilitate evolutionary psychology? Reply to Bjorklund et al. (2022).

Disciplines like evolutionary developmental psychology admirably focus on trying to rehabilitate narrow evolutionary psychology (NEP) from within, by adding a developmental focus to NEP's tenets of adaptationism and computationalism. We argue, however, that these tenets are fundamentally incompatible with taking psychology and its development seriously, and that the kinds of modifications introduced by evolutionary developmental psychologists do not go deep enough to qualitatively change the nondevelopmental outlook of NEP. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Evolving evolutionary psychology.

Which evolutionary theory can best benefit psychological theory, research, and application? The most well-known school of evolutionary psychology has a narrow conceptual perspective (a.k.a., "Narrow Evolutionary Psychology" or NEP). Proponents of NEP have long argued that their brand of evolutionary psychology represents a full-fledged scientific revolution, with Buss (2020) recently likening NEP's scientific impact to that of a Copernican or Darwinian paradigm shift. However, NEP stands on two traditions that are now the subjects of serious debate and revision: the neo-Darwinian adaptationist framework within evolutionary biology, and the computationalist "mind-as-computer" framework within cognitive science. Although NEP calls itself revolutionary, the significant revolutions taking place today in both evolutionary biology and cognitive science reveal NEP to be rooted in the orthodoxies of the past. We propose a more inclusive, developmental evolutionary psychology theory (DEPTH) better suited for our field in multiple ways, from acknowledging epigenesis to incorporating developmental science. To discern appropriate baselines for human nature and for human becoming, one must integrate developmental neuroscience, anthropology, and cognitive archeology. To be of value in addressing and remedying the challenges facing humanity, psychological theories must recognize the central importance of our plasticity, evolved developmental niche, and deep history. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Hearing Better with the Right Eye? The Lateralization of Multisensory Processing Affects Auditory Learning in Northern Bobwhite Quail (Colinus Virginianus) Chicks.

Precocial avian species exhibit a high degree of lateralization of perceptual and motor abilities, including preferential eye use for tasks such as social recognition and predator detection. Such lateralization has been related, in part, to differential experience prior to hatch. That is, due to spatial and resulting postural constraints late in incubation, one eye and hemisphere-generally the right eye / left hemisphere-receive greater amounts of stimulation than the contralateral eye / hemisphere. This raises the possibility that the left hemisphere may specialize or show relative advantages in integrating information across visual and auditory modalities, given that it typically receives greater amounts of multimodal auditory and visual stimulation prior to hatch. The present study represents an initial investigation of this question in a precocial avian species, the Northern bobwhite quail (Colinus virginianus). Day-old bobwhite chicks received 5 min training sessions in which they vocalized to receive contingent playback of a bobwhite maternal call, presented with or without a light that flashed in synchrony with the notes of the call (i.e., bimodal versus unimodal exposure, respectively). Chicks were trained with or without eye patches that allowed them to experience the visual component of the bimodal stimulus with only the left eye (LE), right eye (RE), or both eyes (i.e., binocular; BIN). Finally, the light was placed in various positions relative to the speakers playing the maternal call across three experiments. 24 hrs later chicks were provided a simultaneous choice test between the familiarized and a novel bobwhite maternal call. Given that the right eye and ear typically face outward and are thus unoccluded by the body during late prenatal development, we hypothesized that RE chicks would show facilitated learning under bimodal conditions compared to all other training conditions. This hypothesis was partially confirmed in Experiment 1, when the light was positioned 40 cm above the source of the maternal call. However, we also observed evidence of suppressed learning in chicks provided BIN exposure to the bimodal audio-visual stimulus that was not present during auditory-only training. Experiments 2 and 3 demonstrated that this was likely related to activation of a left-hemisphere dependent fear response when the left eye was exposed to a visual stimulus that loomed above the auditory stimulus. These results indicate that multisensory processing is lateralized in a precocial bird and that these species may thus provide a unique model for studying experience-dependent plasticity of intersensory perception.

Prenatal light exposure influences gait performance and body composition in bobwhite quail chicks.

Maternal nesting behavior, which includes periods of patterned inattention, provides key elements essential for avian embryonic development, including regulation of temperature and light. For example, avian research consistently shows the importance of prenatal light exposure for several developmental processes; however, this research has primarily focused on artificial light regimens (i.e. 24 hr, 0 hr light). Comparatively less is known about how exposure to naturally occurring light patterns during incubation influence motor performance, body composition (i.e. body mass, bone length), and developmental age (incubation length). Here we conducted two experiments which investigated the effects of prenatal light exposure on developmental age, body composition, and gait performance in 1-day-old bobwhite quail. Experiment 1 investigated crepuscular light exposure during the last two days of incubation under two light duration treatments (2 hr & 6 hr) compared to a 12 hr continuous light schedule. Results indicated crepuscular prenatal light experience extended the incubation period for 2 hr exposed embryos, but not for 6 hr exposed embryos and negatively influenced postnatal body composition and postnatal gait performance when compared to 12 hr continuous light embryos. Experiment 2 examined the influence of prenatal light duration (2 hr vs 6 hr) and light presentation (crepuscular vs sporadic). Results demonstrated sporadic light presentation improved gait performance in 2 hr exposed hatchlings, but not 6 hr exposed hatchlings, improved body composition in 6 hr exposed hatchlings, but not 2 hr exposed hatchlings, and did not alter incubation length when compared to crepuscular light counterparts. This study provides further evidence for the importance of maternally regulated sensory stimulation during the prenatal period on early postnatal motor development.

Prenatal incubation temperature affects neonatal precocial birds' locomotor behavior.

Temperature during the prenatal period is an important factor for developing embryos. Extensive human and animal research indicate embryos are sensitive to small fluctuations in temperature which has profound effects on phenotype development. Much of this research has focused on survivability, morphology, and incubation duration, but comparatively less in known about how prenatal temperature influences the development of motor coordination. In this study, we experimentally tested whether exposure to naturally occurring cool (36.9 °C) or warm (38.1 °C) thermal conditions for a brief period (4 days) during early incubation can influence postnatal motor performance in neonatal bobwhite quail hatchlings. We compared gait spatiotemporal parameters, body kinematics, and locomotive behaviors of control chicks incubated in an optimal thermal environment (37.5 °C) with thermally manipulated chicks. Experimental temperature treatment began on embryonic day five (E5) and ended on E8. Chicks were tested 24-h after hatching. Cool thermal exposure during incubation delayed hatching, reduced body mass, and increased fall frequency, intertarsal joint angle and stride length variability during the gait task compared to optimally incubated chicks. Warm thermal exposure during incubation delayed bone growth and increased fall frequency relative to controls. We discuss the relationship between motor development and thermal regulatory processes and provide insight into how spatiotemporal parameters aid in elucidating subtle differences in coordinated movement which may contribute to atypical motor development and be associated with neural developmental disorders. We provide the first spatiotemporal evidence for the importance of optimal thermal microclimates for typical prenatal motor development.

Effects of multimodal synchrony on infant attention and heart rate during events with social and nonsocial stimuli.

Attention is a state of readiness or alertness, associated with behavioral and psychophysiological responses, that facilitates learning and memory. Multisensory and dynamic events have been shown to elicit more attention and produce greater sustained attention in infants than auditory or visual events alone. Such redundant and often temporally synchronous information guides selectivity and facilitates perception, learning, and memory of properties of events specified by redundancy. In addition, events involving faces or other social stimuli provide an extraordinary amount of redundant information that attracts and sustains attention. In the current study, 4- and 8-month-old infants were shown 2-min multimodal videos featuring social or nonsocial stimuli to determine the relative roles of synchrony and stimulus category in inducing attention. Behavioral measures included average looking time and peak look duration, and convergent measurement of heart rate (HR) allowed for the calculation of HR-defined phases of attention: Orienting (OR), sustained attention (SA), and attention termination (AT). The synchronous condition produced an earlier onset of SA (less time in OR) and a deeper state of SA than the asynchronous condition. Social stimuli attracted and held attention (longer duration of peak looks and lower HR than nonsocial stimuli). Effects of synchrony and the social nature of stimuli were additive, suggesting independence of their influence on attention. These findings are the first to demonstrate different HR-defined phases of attention as a function of intersensory redundancy, suggesting greater salience and deeper processing of naturalistic synchronous audiovisual events compared with asynchronous ones.

The influence of prenatal experience on behavioral and social development: The benefits and limitations of an animal model.

Prenatal experience is both a formative and a regulatory force in the process of development. As a result, birth is not an adequate starting point for explanations of behavioral development. However, surprisingly little is currently known regarding the role of prenatal experience in the emergence and facilitation of perceptual, cognitive, or social development. Our lack of knowledge in this area is due in part to the very restricted experimental manipulations possible with human fetuses. A comparative approach utilizing animal models provides an essential step in addressing this gap in our knowledge and providing testable predictions for studies with human fetuses, infants, and children. Further, animal-based comparative research serves to minimize the amount of exploratory research undertaken with human subjects and hone in on issues and research directions worthy of further research investment. In this article, I review selected animal-based research exploring how developmental influences during the prenatal period can guide and constrain subsequent behavioral and social development. I then discuss the importance of linking the prenatal environment to postnatal outcomes in terms of how psychologists conceptualize "innate" biases, preferences, and skills in the study of human development.

The intersensory redundancy hypothesis: Extending the principle of unimodal facilitation to prenatal development.

Selective attention to different properties of stimulation provides the foundation for perception, learning, and memory. The Intersensory Redundancy Hypothesis (IRH) proposes that early in development information presented redundantly across two or more modalities (multimodal) selectively recruits attention to and enhances perceptual learning of amodal properties, whereas information presented to a single sense modality (unimodal) enhances perceptual learning of modality-specific properties. The present study is the first to assess this principle of unimodal facilitation in non-human animals in prenatal development. We assessed bobwhite quail embryos' prenatal detection of pitch, a modality-specific property, under conditions of unimodal and bimodal (synchronous or asynchronous) exposure. Chicks exposed to prenatal unimodal auditory stimulation or asynchronous bimodal (audiovisual) stimulation preferred the familiarized maternal call over a novel pitch-modified maternal call following hatching, whereas chicks exposed to redundant (synchronous) audiovisual stimulation failed to prefer the familiar call over the pitch-modified call. These results provide further evidence that selective attention is recruited to specific stimulus properties of events in early development and that these biases are evident even during the prenatal period.

Coordinated movement is influenced by prenatal light experience in bobwhite quail chicks (Colinus virginianus).

Sensory-motor development begins early during embryogenesis and is influenced by sensory experience. Little is known about the prenatal factors that influence the development of motor coordination. Here we investigated whether and to what extent prenatal light experience can influence the development of motor coordination in bobwhite quail hatchlings. Quail embryos were incubated under four light conditions: no light (dark), 2h of total light (2HR), 6h of total light (6HR), and diffused sunlight (controls). Hatchlings were video recording walking down a runway at three developmental ages (12, 24, and 48h). Videos were assessed for forward locomotion, a measurement of motor coordination, falls, a measurement of motor instability, and motivation to complete the task. We anticipated a linear decline of coordination with a reduction in prenatal light experience and improved coordination with age. Furthermore, as motor coordination becomes more laborious we anticipated motivation to complete the task would decline. However, our findings revealed hatchlings did not uniformly improve with age as expected, nor did the reduction of light result in a linear reduction in motor coordination. Instead, we found a more complex relationship with 6HR and 2HR hatchlings showing distinct patterns of stability and instability. Similarly, we found a reduction in motivation within the 6HR light condition. It appears that prenatal light exposure influences the development of postnatal motor coordination and we discuss these finding in light of neurodevelopmental processes influenced by light experience.

Developmental evolution.

Biologists and psychologists are re-thinking the long-standing premise of genes as the primary cause of development, a view widely embraced in 20th-century biology. This shift in thinking is based in large part on: (1) the growing appreciation of the complex, distributed regulatory dynamics of gene expression; and (2) the growing appreciation of the probabilistic, contingent, and situated nature of development. We now appreciate that what actually unfolds during individual development represents only one of many possibilities. This expanded focus on the developmental process, often referred to as a developmental systems approach, has far-reaching implications for developmental and evolutionary theory, including new ways of thinking about the consequences of activity and experience, the emergence of novel properties or traits, the nature and extent of heredity, and the origins of phenotypic variability. WIREs Cogn Sci 2017, 8:e1422. doi: 10.1002/wcs.1422 For further resources related to this article, please visit the WIREs website.

Elevated yolk progesterone moderates prenatal heart rate and postnatal auditory learning in bobwhite quail (Colinus virginianus).

Previous studies have established that yolk hormones of maternal origin can influence physiology and behavior in birds. However, few studies have examined the effects of maternal gestagens, like progesterone, on chick behavior and physiology. We tested the effects of experimentally elevated egg yolk progesterone on embryonic heart rate and postnatal auditory learning in bobwhite quail hatchlings. Quail chicks were passively exposed to an individual maternal assembly call for 10 min/hr during the 24 hr following hatching. Preference for the familiarized call was tested at 48 hr following hatching in three experimental groups: chicks that received artificially elevated yolk progesterone (P) prior to incubation, vehicle-only controls (V), and non-manipulated controls (C). Resting heart rate of P, V, and C embryos were also measured on prenatal day 17. The resting heart rate of P embryos was significantly higher than both the V and C embryos. Chicks from the P group also showed an enhanced preference for the familiarized bobwhite maternal call when compared to chicks from the C and V groups. Our results indicate that elevated yolk progesterone in pre-incubated bobwhite quail eggs can influence arousal level in bobwhite embryos and postnatal perceptual learning in bobwhite neonates.

Intrasensory Redundancy Facilitates Infant Detection of Tempo: Extending Predictions of the Intersensory Redundancy Hypothesis.

Research has demonstrated that intersensory redundancy (stimulation synchronized across multiple senses) is highly salient and facilitates processing of amodal properties in multimodal events, bootstrapping early perceptual development. The present study is the first to extend this central principle of the intersensory redundancy hypothesis (IRH) to certain types of intrasensory redundancy (stimulation synchronized within a single sense). Infants were habituated to videos of a toy hammer tapping silently (unimodal control), depicting intersensory redundancy (synchronized with a soundtrack) or intrasensory redundancy (synchronized with another visual event; light flashing or bat tapping). In Experiment 1, 2-month-olds showed both intersensory and intrasensory facilitation (with respect to the unimodal control) for detecting a change in tempo. However, intrasensory facilitation was found when the hammer was synchronized with the light flashing (different motion) but not with the bat tapping (same motion). Experiment 2 tested 3-month-olds using a somewhat easier tempo contrast. Results supported a similarity hypothesis: intrasensory redundancy between two dissimilar events was more effective than that between two similar events for promoting processing of amodal properties. These findings extend the IRH and indicate that in addition to intersensory redundancy, intrasensory redundancy between two synchronized dissimilar visual events is also effective in promoting perceptual processing of amodal event properties.

Increased yolk progesterone interferes with prenatal auditory learning and elevates emotional reactivity in bobwhite quail (Colinus virginianus) chicks.

Avian eggs contain maternally derived hormones, including testosterone and progesterone. Little is currently known about the effects of these hormones on early behavioral development. We assessed the effects of elevated levels of progesterone levels on prenatal perceptual learning and postnatal emotional reactivity in Northern bobwhite quail. Prior to incubation, eggs received an injection of either progesterone (P) or oil vehicle (V). In P eggs, levels of progesterone were elevated two standard deviations above the mean based on ELISA analysis of progesterone yolk concentrations from a previous study. A third group of eggs served as controls and received no injection (C). Chicks hatched from P eggs displayed elevated levels of emotional reactivity compared to V and C chicks in a tonic immobility task and a hole-in-the-wall emergence task. Chicks from P eggs also failed to demonstrate a preference for a familiarized bobwhite maternal call that had been presented prenatally. In contrast, the V and C chicks demonstrated a significant preference for the familiarized maternal call following hatching, indicating prenatal auditory learning. Our results are consistent with previous findings from precocial birds demonstrating that hormones of maternal origin can influence prenatal perceptual learning as well as emotional reactivity in the period following hatching..

Developmental evolution and the origins of phenotypic variation.

Because of the variability of relevant developmental resources across different environments, and because only a portion of the genome is expressed in any individual organism as a result of its specific developmental context and experience, what is actually realized during the course of individual development represents only one of many possibilities. One conclusion to be drawn from this insight is that the origin of phenotypic traits and their variation can be traced to the process of development. In this conceptual overview, I briefly explore how recent efforts to integrate genetic, epigenetic, and environmental levels of analysis through a developmental lens is advancing our understanding of the generation of the stability and variability of phenotypic outcomes observed within and across generations. A growing body of evidence indicates that phenotypes are the outcomes of the whole developmental system, comprised of the organism, with its particular genetic and cellular make-up in its specific physical, biological, and social environments. I conclude that the emergent products of development are epigenetic, not just genetic, and evolutionary explanation cannot be complete without a developmental mode of analysis.

Neural correlates of intersensory processing in 5-month-old infants.

Two experiments assessing event-related potentials in 5-month-old infants were conducted to examine neural correlates of attentional salience and efficiency of processing of a visual event (woman speaking) paired with redundant (synchronous) speech, nonredundant (asynchronous) speech, or no speech. In Experiment 1, the Nc component associated with attentional salience was greater in amplitude following synchronous audiovisual as compared with asynchronous audiovisual and unimodal visual presentations. A block design was utilized in Experiment 2 to examine efficiency of processing of a visual event. Only infants exposed to synchronous audiovisual speech demonstrated a significant reduction in amplitude of the late slow wave associated with successful stimulus processing and recognition memory from early to late blocks of trials. These findings indicate that events that provide intersensory redundancy are associated with enhanced neural responsiveness indicative of greater attentional salience and more efficient stimulus processing as compared with the same events when they provide no intersensory redundancy in 5-month-old infants.

Learning to Attend Selectively: The Dual Role of Intersensory Redundancy.

Selective attention is the gateway to perceptual processing, learning, and memory, and is a skill honed through extensive experience. However, little research has focused on how selective attention develops. Here we synthesize established and new findings assessing the central role of redundancy across the senses in guiding and constraining this process in infancy and early childhood. We highlight research demonstrating the dual role of intersensory redundancy -- its facilitating and interfering effects-- on detection and perceptual processing of various properties of objects and events.

The origins of variation: evolutionary insights from developmental science.

Evidence from contemporary epigenetic research indicates that it is not biologically meaningful to discuss genes without reference to the molecular, cellular, organismal, and environmental context within which they are activated and expressed. Genetic and nongenetic factors, including those beyond the organism, constitute a dynamic relational developmental system. This insight highlights the importance of bringing together genetics, development, and ecology into one explanatory framework for a more complete understanding of the emergence and maintenance of phenotypic stability and variability. In this Chapter, I review some examples of this integrative effort and explore its implications for developmental and evolutionary science, with a particular emphasis on the origins of phenotypic novelty. I argue that developmental science is critical to this integrative effort, in that evolutionary explanation cannot be complete without developmental explanation. This is the case because the process of development generates the phenotypic variation on which natural selection can act.