Visual Imprinting in Birds: Behavior, Models, and Neural Mechanisms.

Brian J. McCabe

doi:10.3389/fphys.2019.00658

Abstract

Filial imprinting is a process, readily observed in precocial birds, whereby a social attachment is established between a young animal and an object that is typically (although not necessarily) a parent. During a perinatal sensitive period, the young animal learns characteristics of the object (the imprinting stimulus) simply by being exposed to it and will subsequently recognize and selectively approach this stimulus. Imprinting can thus establish a filial bond with an individual adult: a form of social cohesion that may be crucial for survival. Behavioral predispositions can act together with the learning process of imprinting in the formation, maintenance, and modification of the filial bond. Memory of the imprinting stimulus, as well as being necessary for social recognition, is also used adaptively in perceptual classification of sensory signals. features of an imprinting stimulus, such as similarity or difference between stimulus components, can also be recognized. Studies of domestic chicks have elucidated the neural basis of much of the above behavior. This article discusses (1) principal behavioral characteristics of filial imprinting and related predispositions, (2) theoretical models that have been developed to account for this behavior, and (3) physiological results elucidating the underlying neural mechanisms. Interactions between these different levels of analysis have resulted in advancement of all of them. Taken together, the different approaches have helped define strategies for investigating mechanisms of learning, memory, and perception.

Highlights

Filial imprinting has been recognized since antiquity and its behavioral characteristics reviewed extensively (Heinroth, 1911; Lorenz, 1935, 1937; Bateson, 1966; Sluckin, 1972; Hess, 1973; Bolhuis, 1991)
It is readily observed in the young of many precocial species and most of the available information comes from newly hatched galliform birds such as chickens, ducks, and quail
A group of chicks rather than an individual animal was used in this experiment, the results provide evidence of remarkable learning-dependent discrimination between naturalistic stimuli, such as may be engaged in learning the features of an individual

Summary

INTRODUCTION

Filial imprinting has been recognized since antiquity and its behavioral characteristics reviewed extensively (Heinroth, 1911; Lorenz, 1935, 1937; Bateson, 1966; Sluckin, 1972; Hess, 1973; Bolhuis, 1991). As well as the evidence for learning-related functional synaptic modification in the IMM, on the left side of this structure, single unit recording in freely moving chicks has shown that neuronal responsiveness in the IMM to a visual imprinting stimulus increases as a result of imprinting training (Brown and Horn, 1994; Nicol et al, 1995; Horn et al, 2001; Nicol and Horn, 2009). Exogenous T3, known to extend the sensitive period for imprinting (Yamaguchi et al, 2012), was found to enhance the preference for biological motion, providing a physiological link between imprinting, the sensitive period for imprinting, and the predisposition to prefer biological motion (Miura et al, 2018)

A Predisposition to Learn

CONCLUSION