Animal Imprinting Psychology: The Science Behind the Bond

Animal imprinting is a form of learning in which a young animal forms an attachment to a specific stimulus during a limited developmental window, with consequences that can persist into adulthood. This article examines the psychological mechanisms of imprinting, including critical periods, neural pathways, and long-term effects, with emphasis on what the research evidence shows about how imprinting works in birds and mammals. The content is intended for students, researchers, life-science professionals, and informed general readers who want a grounded understanding of the science.

What Imprinting Means in Animal Psychology

Imprinting refers to a learning process that occurs during a restricted period early in life, during which an animal acquires a preference for or attachment to a particular stimulus. In precocial birds such as geese, ducks, and chickens, baby birds learn the characteristics of the first moving object they see within a critical period, imprint on it, and follow it around. This behavior is an example of learning and memory acquisition in infancy, and it has been studied extensively to understand the neural mechanisms of early learning (NCBI Literature Resources, PubMed).

The term imprinting also appears in other contexts that are distinct from filial imprinting. Genomic imprinting refers to the epigenetic silencing of genes based on parental origin, a process unrelated to behavioral learning but sharing the name. Hormonal imprinting refers to the perinatal period when developing hormone receptors meet hormones for the first time, establishing receptor-hormone connections that can last for life. This article focuses primarily on filial imprinting, the behavioral process by which young animals form social attachments, while noting where related concepts apply.

The scientific study of imprinting has a long history in ethology, the biological study of animal behavior. Research on filial imprinting has yielded insights into a range of behavioral and neurobiological phenomena, and these insights have fed back to elucidate behavioral development more broadly (Filial Imprinting: Behaviour and Neurobiology). Understanding imprinting matters for animal husbandry because it affects how young animals bond with mothers, how they respond to handlers, and how they adapt to rearing environments.

Critical Periods and Sensitive Periods in Development

Experience exerts a profound influence on the brain and therefore on behavior. When the effect of experience on the brain is particularly strong during a limited period in development, this period is referred to as a sensitive period. Such periods allow experience to instruct neural circuits to process or represent information in a way that is adaptive for the individual. When experience provides information that is essential for normal development and alters performance permanently, such sensitive periods are referred to as critical periods (Sensitive periods in the development of the brain and behavior).

The distinction between sensitive and critical periods carries practical weight. A sensitive period is a window during which experience has a particularly strong influence on neural development. A critical period is a specific type of sensitive period in which the experience is essential for normal development and the absence of that experience leads to permanent alteration. In filial imprinting, the first few days after hatching constitute the sensitive period during which chicks can form social attachments. After this period, chicks raised in darkness cannot be imprinted (Wnt-2b in the intermediate hyperpallium apicale of the telencephalon is critical for the thyroid hormone-mediated opening of the sensitive period for filial imprinting in domestic chicks).

Sensitive periods are actually a property of neural circuits instead of behavior alone. Mechanisms of plasticity at the circuit level operate during sensitive periods, and experience during a sensitive period modifies the architecture of a circuit in fundamental ways, causing certain patterns of connectivity to become highly stable and therefore energetically preferred. Plasticity that occurs beyond the end of a sensitive period, which is substantial in many circuits, alters connectivity patterns within the architectural constraints established during the sensitive period (Sensitive periods in the development of the brain and behavior).

The concept of a sensitive period in mother-to-infant attachment has been subject to critical scrutiny. A review of the bonding concept concluded that there are no indications from animal investigations and no evidence from human studies that directly support the notion of a sensitive period in the formation of mother-to-infant attachments. The authors cautioned that the term bonding is often misleading because of a tendency to reify and simplify attachment phenomena (Mother-to-infant bonding). This distinction matters for practical applications: the evidence for critical periods in filial imprinting in birds is strong, but the extension of that concept to mammalian mother-infant bonding requires more caution.

Neural Pathways of Filial Imprinting

Research on the domestic chick has identified a specific neural circuit that mediates visual filial imprinting. Information pertaining to a visual imprinting stimulus is recognized and processed in the visual Wulst, a region that corresponds to the mammalian visual cortex. It is then transmitted to the posterior region of the telencephalon, followed by the core region of the hyperpallium densocellulare (HDCo), the periventricular region of the hyperpallium densocellulare (HDPe), and finally the intermediate medial mesopallium (IMM), a region similar to the mammalian association cortex. Memory is stored in the IMM (Neurobiology of imprinting).

After imprint training, plastic changes are observed in the visual Wulst as well as in the neurons of this circuit. HDCo cells, located at the center of this circuit, express N-methyl-D-aspartate (NMDA) receptors containing the NR2B subunit, and the expression of this receptor increases after imprint training. Inhibition of this receptor in the cells of the HDCo region leads to failure of imprinting and inactivation of the circuit. Thus, NMDA receptors bearing the NR2B subunit play a critical role in plastic changes in this circuit and in the induction of imprinting (Neurobiology of imprinting).

The intermediate medial mesopallium (IMM) in the chick forebrain is a site of memory encoding for imprinting. Electrophysiological, neuroanatomical, pharmacological, biochemical, and ablation studies have implicated the IMM in the recognition of individual conspecifics, and recent research has elucidated the underlying neurobiological mechanisms at the cellular and sub-cellular levels (Filial Imprinting: Behaviour and Neurobiology). The neural pathway from the IMM to the intermediate hyperpallium apicale (IMHA) is critical for filial imprinting in domestic chicks (Critical role of the neural pathway from the intermediate medial mesopallium to the intermediate hyperpallium apicale in filial imprinting of domestic chicks).

Structural plasticity in newborn chickens is regulated by the mTORC1 signaling pathway, which is involved in filial imprinting (Regulation of filial imprinting and structural plasticity by mTORC1 in newborn chickens). This finding connects the molecular mechanisms of imprinting to broader processes of synaptic remodeling and memory formation.

Hormonal Regulation of the Sensitive Period

The timing of the sensitive period for filial imprinting is regulated by thyroid hormone. Imprinting training in chicks causes rapid inflow of the thyroid hormone 3,5,3'-triiodothyronine (T3), converted from circulating plasma thyroxine by the enzyme type 2 iodothyronine deiodinase (Dio2) in brain vascular endothelial cells. The T3 initiates and extends the sensitive period to last more than one week via non-genomic mechanisms and primes subsequent learning. Even in non-imprinted chicks whose sensitive period has ended, exogenous T3 enables imprinting (Thyroid hormone determines the start of the sensitive period of imprinting and primes later learning).

The molecular mechanism downstream of T3 involves Wnt signaling. Wnt-2b mRNA levels increase in the T3-injected telencephalon of 4-day-old chicks. Pharmacological inhibition of Wnt signaling in the intermediate hyperpallium apicale (IMHA), the caudal area of the telencephalon, blocks the recovery of the sensitive period following T3 injection. Injection of recombinant Wnt-2b protein into the IMHA helps chicks recover the sensitive period without the injection of T3. Wnt signaling is also involved in imprinting via the IMHA region on day 1 during the sensitive period. These results indicate that Wnt signaling plays a critical role in the opening of the sensitive period downstream of T3 (Wnt-2b in the intermediate hyperpallium apicale of the telencephalon is critical for the thyroid hormone-mediated opening of the sensitive period for filial imprinting in domestic chicks).

The role of thyroid hormone in imprinting has broader implications for understanding attachment and early life stress. Replicated findings show critical roles of the conversion of thyroid prohormone by Dio2 into T3 in the regulation of the timing of imprinting learning. Because of the interactions of T3 with oxytocinergic and dopaminergic neurons of the hypothalamic paraventricular nucleus, these findings provide new neuroendocrinological insight for possible relations with both attachment and metabolic sequelae of early life stress (Research evidence from studies on filial imprinting, attachment, and early life stress).

Imprinting in Mammals and Farm Species

In buffaloes and other mammalian farm species, the mother provides food and protection to the young, but she is also the main source of behavioral and social learning for the offspring. It is important that mother and young establish a bond based on a learning mechanism defined as imprinting early after parturition during the sensitive period, on which the welfare and survival of the offspring will depend. Touch, hearing, vision, and smell seem to be the predominant senses involved during imprinting in buffaloes and other farm animals (Neurophysiological Mechanisms of Cow-Calf Bonding in Buffalo and Other Farm Animals).

The review of cow-calf bonding in buffaloes and other farm animals describes how bonding can be classified according to the predominant senses used by different species, the importance of learning in the development of the mother-young relationship, and the neurobiological mechanisms involved. Factors that can affect the mother-young relationship in the field include separation at birth, interference with sensory contact, and management practices that disrupt the early postpartum period (Neurophysiological Mechanisms of Cow-Calf Bonding in Buffalo and Other Farm Animals).

The relationship between imprinting and attachment theory is complex. Attachment is a concept that was developed and researched in developmental psychology in uptake of findings on filial imprinting from ethology. In the present period, attachment concepts are increasingly applied to and investigated in animal research, thereby translating back criteria that were established for human infants. Findings on filial imprinting are becoming more forgotten, while basic findings in human infants are not reflected in investigations on attachment in animals (Research evidence from studies on filial imprinting, attachment, and early life stress).

Attachment theory took its current form in John Bowlby's amalgamation of ideas from psychoanalysis, developmental psychology, and ethology. Bowlby's interest in Lorenz's concept of imprinting has been subject to historical and biographical studies, leaving a fine-grained theoretical scrutiny of the exact relationship between imprinting and attachment still pending. The analysis of the links between these processes brings to the foreground the distinction between supra-individual versus individual aspects of bonding, the relevance of proto-attachment phases before proper Bowlbyan attachment is attained, and the role of communicative signals during such early phases (Back to basics: A re-evaluation of the relevance of imprinting in the genesis of Bowlby's attachment theory).

At a Glance: Key Concepts in Imprinting Psychology

The Role of Voluntary Behavior in Imprinting Strength

The strength of imprinting depends on the nature of the following response. An experiment was performed to determine the effect on imprinting strength of forcing the following response during the critical period in chicks. Results of the procedures used indicate that although imprinting occurred with forced following, it was not as strong as it is when the following is voluntary (Imprinting by force).

This finding has practical implications for rearing systems. When young birds are forced to follow a stimulus, they may form an imprint, but the attachment is weaker than when they follow voluntarily. Rearing protocols that allow chicks to approach and follow a brood hen or imprinting stimulus at their own pace are likely to produce stronger attachments than protocols that force contact.

The reversibility of imprinting preferences has also been studied. Research has examined the reversal of a preference established during the critical period (Imprinting: reversal of a preference established during the critical period) and the reversibility of imprinting more generally (Reversibility of imprinting). These studies indicate that imprinting preferences are not necessarily permanent and can be modified under certain conditions, although the extent of reversibility depends on the timing and nature of the new experience.

Recognition and Preference Formation in Imprinting

Imprinting entails recognition of stimuli in terms of both form and certain abstract features. A striking property of imprinting is the development of a preference for a stimulus slightly different from one that has become familiar, a property having profound implications for survival (Filial Imprinting: Behaviour and Neurobiology). This preference for novelty within a familiar category allows young animals to recognize their mother or siblings while remaining responsive to individual variation.

The study of imprinting in chicks has led to the discovery of analogous processes in humans and promises to yield insights into cognitive development in both species (Filial Imprinting: Behaviour and Neurobiology). This cross-species relevance makes imprinting research valuable beyond the immediate context of animal behavior.

Mate preference learning, where individuals learn to prefer or avoid specific phenotypes during mate selection, is pervasive across animal taxa and influences reproductive isolation and trait evolution. Research in Bicyclus anynana butterflies has shown that valence attribution during learning may not be restricted to transcriptional changes in the brain. The antennae show higher transcriptomic changes during negative training and the eyes show higher transcriptomic changes during positive training, relative to the naive control. A subset of genes in each tissue changed expression patterns with valence, and genes previously linked to classical conditioning pathways were identified, supporting the hypothesis that imprinting-like learning and classical conditioning share molecular mechanisms (Divergent sensory transcriptomic profiles in positive and negative learning in Bicyclus anynana butterflies).

Practical Assessment of Imprinting in Rearing Systems

For farmers and animal managers, assessing whether imprinting has occurred requires systematic observation and record keeping. The following steps provide a practical framework for evaluating imprinting in poultry and mammalian livestock.

Step 1: Document the timing of first exposure. Record the age of the animal at first exposure to the imprinting stimulus. For chicks, the sensitive period is the first 2 to 3 days after hatching (Wnt-2b in the intermediate hyperpallium apicale of the telencephalon is critical for the thyroid hormone-mediated opening of the sensitive period for filial imprinting in domestic chicks). For mammalian species, the sensitive period begins at parturition, and the timing of first contact between mother and young should be recorded.

Step 2: Observe following and approach behavior. Measure whether the young animal approaches and follows the imprinting stimulus when given the opportunity. Voluntary following produces stronger imprinting than forced following (Imprinting by force). Record the latency to approach, the duration of following, and whether the behavior occurs consistently across multiple observations.

Step 3: Test discrimination. Present the imprinted stimulus alongside a novel stimulus of the same general category. An imprinted animal should show a clear preference for the familiar stimulus. The development of a preference for a stimulus slightly different from one that has become familiar is a normal property of imprinting (Filial Imprinting: Behaviour and Neurobiology).

Step 4: Record distress responses. When separated from the imprinting stimulus, a successfully imprinted animal typically shows distress vocalizations and attempts to re-establish contact. The absence of these responses may indicate failed imprinting.

Step 5: Monitor long-term social behavior. Imprinting affects social behavior beyond the immediate post-hatching or postpartum period. Observe whether the animal maintains social proximity to the imprinting stimulus or its species-typical equivalents as it matures.

Records and Measurements for Imprinting Assessment

Common Failure Patterns in Imprinting

Several management practices can interfere with successful imprinting. Recognizing these patterns allows for early intervention.

Delayed first exposure. When young animals are not exposed to an appropriate imprinting stimulus within the sensitive period, imprinting fails. Chicks raised in darkness beyond the first 2 to 3 days after hatching cannot be imprinted (Wnt-2b in the intermediate hyperpallium apicale of the telencephalon is critical for the thyroid hormone-mediated opening of the sensitive period for filial imprinting in domestic chicks). In mammalian species, separation of mother and young during the immediate postpartum period can disrupt bond formation.

Forced following. When chicks are forced to follow an imprinting stimulus, imprinting occurs but is weaker than with voluntary following (Imprinting by force). Rearing systems that confine chicks in close proximity to a stimulus without allowing approach and retreat behavior may produce weaker attachments.

Inappropriate stimulus characteristics. Imprinting stimuli must have certain characteristics to be effective. The stimulus must be moving and visually salient for chicks. Stimuli that lack these properties may not elicit following behavior or may produce weak imprinting.

Interference during the sensitive period. Stress, illness, or environmental disruption during the sensitive period can interfere with imprinting. The neural mechanisms of imprinting require intact sensory processing and memory formation, both of which can be disrupted by physiological stress.

Cross-species imprinting. Young animals may imprint on humans or other species if those are the first moving objects they encounter. This can complicate later social development and management, particularly if the animal later needs to bond with conspecifics.

Welfare and Safety Context

Imprinting has direct welfare implications. The mother-young bond, established through imprinting during the sensitive period, is important for the welfare and survival of the offspring in buffaloes and other farm species (Neurophysiological Mechanisms of Cow-Calf Bonding in Buffalo and Other Farm Animals). Failure to establish this bond can lead to poor nutrition, increased stress, and higher mortality.

The concept of bonding has been criticized for its use in clinical and social work practice. A critical review concluded that the usage of the term bonding is often misleading because of a tendency to reify and simplify attachment phenomena, and the authors described negative and pessimistic implications of using this concept in social work and clinical practice (Mother-to-infant bonding). This caution applies to animal management as well: labeling an animal as unbonded can lead to assumptions about permanent impairment that may not be justified.

The hormonal regulation of the sensitive period has implications for understanding early life stress. The interactions of T3 with oxytocinergic and dopaminergic neurons of the hypothalamic paraventricular nucleus provide new neuroendocrinological insight for possible relations with both attachment and metabolic sequelae of early life stress (Research evidence from studies on filial imprinting, attachment, and early life stress). Animals that experience disrupted imprinting may show long-term alterations in stress physiology and metabolic function.

Limitations of Imprinting Research

The research on imprinting has several limitations that should be acknowledged. Much of the detailed neural work has been conducted in domestic chicks, and the extent to which these findings generalize to other species is not fully established. The neural circuit identified in chicks, involving the visual Wulst, HDCo, HDPe, and IMM, is specific to birds, and mammalian imprinting may involve different pathways.

The concept of a sensitive period in mother-to-infant bonding in humans has been questioned. A review found no evidence from human studies that directly supports the notion of a sensitive period in the formation of mother-to-infant attachments (Mother-to-infant bonding). This finding does not negate the importance of early contact, but it cautions against assuming that missed early contact produces permanent bonding failure.

The reversibility of imprinting is not fully understood. Studies have demonstrated reversal of preferences established during the critical period (Imprinting: reversal of a preference established during the critical period) and reversibility of imprinting (Reversibility of imprinting), but the conditions under which reversal occurs and the limits of reversibility require further research.

The distinction between filial imprinting and other forms of early learning is not always clear. The ontogeny of behavior involves multiple processes that interact during development (Ontogeny of behaviour), and isolating the specific contribution of imprinting from other learning processes can be difficult.

Professional Escalation Criteria

Animal managers should seek professional advice when imprinting failures have welfare or production consequences. The following situations warrant consultation with a veterinarian, animal behaviorist, or poultry specialist.

Persistent failure to bond. If a young animal shows no following behavior, no preference for the mother or brood hen, and no distress upon separation beyond the expected sensitive period, professional assessment is warranted.

Aggression or avoidance directed at the mother. When a young animal actively avoids or shows aggression toward its mother or brood hen, this may indicate failed imprinting or a disrupted bond.

Failure to thrive despite adequate nutrition. Young animals that do not gain weight or show poor growth despite access to feed may have failed to learn appropriate feeding behavior from the mother, which can be a consequence of disrupted imprinting.

Abnormal social development. Young animals that fail to develop species-typical social behavior, such as flocking in birds or herd behavior in mammals, may have experienced imprinting failure.

Cross-species imprinting complications. When animals have imprinted on humans and show aggression toward conspecifics or fail to mate with their own species, professional guidance on management options is needed.

Frequently Asked Questions

What is the difference between imprinting and attachment?

Imprinting is a specific learning process that occurs during a limited sensitive period early in life, during which a young animal forms a preference for a particular stimulus. Attachment is a broader concept developed in developmental psychology that describes the emotional bond between an infant and caregiver. Attachment theory took its current form in John Bowlby's amalgamation of ideas from psychoanalysis, developmental psychology, and ethology, and Bowlby was interested in Lorenz's concept of imprinting (Back to basics: A re-evaluation of the relevance of imprinting in the genesis of Bowlby's attachment theory). The relationship between the two concepts remains a subject of theoretical scrutiny.

How long does the critical period for imprinting last in chicks?

The sensitive period for filial imprinting in domestic chicks is the first 2 to 3 days after hatching. After this period, chicks raised in darkness cannot be imprinted (Wnt-2b in the intermediate hyperpallium apicale of the telencephalon is critical for the thyroid hormone-mediated opening of the sensitive period for filial imprinting in domestic chicks). The thyroid hormone T3 determines the start of the sensitive period, and exogenous T3 can enable imprinting even after the sensitive period has ended (Thyroid hormone determines the start of the sensitive period of imprinting and primes later learning).

Can imprinting be reversed?

Research has demonstrated that preferences established during the critical period can be reversed under certain conditions. Studies have examined the reversal of a preference established during the critical period (Imprinting: reversal of a preference established during the critical period) and the reversibility of imprinting (Reversibility of imprinting). The conditions under which reversal occurs and the limits of reversibility depend on the timing and nature of the new experience.

What brain regions are involved in filial imprinting?

In domestic chicks, visual imprinting information is processed in the visual Wulst, then transmitted to the posterior telencephalon, the core and periventricular regions of the hyperpallium densocellulare (HDCo and HDPe), and finally the intermediate medial mesopallium (IMM), where memory is stored. NMDA receptors bearing the NR2B subunit in HDCo cells play a critical role in plastic changes in this circuit and in the induction of imprinting (Neurobiology of imprinting). The IMM is a site of memory encoding for imprinting (Filial Imprinting: Behaviour and Neurobiology).

How does thyroid hormone affect imprinting?

Thyroid hormone T3 determines the start of the sensitive period for imprinting. Imprinting training causes rapid inflow of T3, converted from circulating plasma thyroxine by the enzyme Dio2 in brain vascular endothelial cells. The T3 initiates and extends the sensitive period and primes subsequent learning. Even in non-imprinted chicks whose sensitive period has ended, exogenous T3 enables imprinting (Thyroid hormone determines the start of the sensitive period of imprinting and primes later learning). Wnt signaling plays a critical role in the opening of the sensitive period downstream of T3 (Wnt-2b in the intermediate hyperpallium apicale of the telencephalon is critical for the thyroid hormone-mediated opening of the sensitive period for filial imprinting in domestic chicks).

Does forced following produce weaker imprinting than voluntary following?

Yes. An experiment on the effect of forcing the following response during the critical period in chicks found that although imprinting occurred with forced following, it was not as strong as when the following is voluntary (Imprinting by force). This finding supports rearing approaches that allow young animals to approach and follow imprinting stimuli at their own pace.

How does imprinting differ between birds and mammals?

In birds, imprinting involves a specific neural circuit including the visual Wulst and IMM, and the process is regulated by thyroid hormone. In mammals such as buffaloes and other farm species, the mother-young bond is established through a learning mechanism defined as imprinting early after parturition during the sensitive period, with touch, hearing, vision, and smell as the predominant senses involved (Neurophysiological Mechanisms of Cow-Calf Bonding in Buffalo and Other Farm Animals). The neural mechanisms in mammals are less well characterized than in birds.

What is the relationship between imprinting and mate preference learning?

Mate preference learning, where individuals learn to prefer or avoid specific phenotypes during mate selection, is pervasive across animal taxa. Research in Bicyclus anynana butterflies has shown that valence attribution during learning involves tissue-specific transcriptional responses in sensory and brain tissues, and genes previously linked to classical conditioning pathways were identified, supporting the hypothesis that imprinting-like learning and classical conditioning share molecular mechanisms ([Div

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References and Further Reading

• NCBI Literature Resources. National Center for Biotechnology Information.
• PubMed. National Library of Medicine.
• Sensitive periods in the development of the brain and behavior.. Journal of cognitive neuroscience, 2004.
• [Neurobiology of imprinting].. Brain and nerve = Shinkei kenkyu no shinpo, 2012.
• Mother-to-infant bonding.. Journal of child psychology and psychiatry, and allied disciplines, 1982.
• Imprinting by force.. Science (New York, N.Y.), 1962.
• Wnt-2b in the intermediate hyperpallium apicale of the telencephalon is critical for the thyroid hormone-mediated opening of the sensitive period for filial imprinting in domestic chicks (Gallus gallus domesticus).. Hormones and behavior, 2018.
• Ontogeny of behaviour.. British medical bulletin, 1981.
• Imprinting: reversal of a preference established during the critical period.. Nature, 1967.
• Reversibility of imprinting.. Journal of comparative and physiological psychology, 1968.
• Filial Imprinting: Behaviour and Neurobiology.. 2026.
• Genomic Imprinting, Epigenetic Dysregulation, and Neuropsychiatric Mechanisms in Prader-Willi Syndrome: A Multi-Level Integrative Review.. 2026.
• The hallmarks of neuro-immune reprogramming in cancer.. 2026.
• Divergent sensory transcriptomic profiles in positive and negative learning in Bicyclus Anynana butterflies.. 2026.
• Intergenerational neuroimaging's present and future: Considering sex as a biological variable to enhance knowledge of brain development through parent-offspring similarity.. 2025.
• Toward Rational Design of Imprinted Proteins Based on Albumins: Computational and Experimental Studies.. 2026.
• Research evidence from studies on filial imprinting, attachment, and early life stress: a new route for scientific integration. Acta Ethologica, 2020.
• The Examination of a Critical Period of the Following Response in Chicks and the Effects of the Rearing and the Exposing Conditions of Imprinting Stimulus on the Response. 1981.
• Environmental Pollution and Non-Perinatal Faulty Hormonal Imprinting: A Critical Review. Integrative Pediatrics and Child Care, 2018.
• Neurophysiological Mechanisms of Cow-Calf Bonding in Buffalo and Other Farm Animals. Animals, 2021.
• Thyroid hormone determines the start of the sensitive period of imprinting and primes later learning. Nature Communications, 2012.
• Back to basics: A re-evaluation of the relevance of imprinting in the genesis of Bowlby’s attachment theory. Frontiers in Psychology, 2022.
• Imprinting: Drug-produced isolation and the sensitive period. Nature, 1968.
• Critical role of the neural pathway from the intermediate medial mesopallium to the intermediate hyperpallium apicale in filial imprinting of domestic chicks (Gallus gallus domesticus). Neuroscience, 2015.
• Regulation of filial imprinting and structural plasticity by mTORC1 in newborn chickens. Scientific Reports, 2018.

This article is educational and does not replace institutional policy, professional advice, or applicable safety and regulatory requirements.