Chapter 7 - 5

05 Psychology

Imprinting

It is often used as a striking image for the importance of early.

childhood experience: newly hatched ducks and geese follow the first moving object they see and treat it as their mother.

This is a phenomenon known as imprinting.

This special form of learning, explored by Konrad Lorenz in 1935, has drawn continuous interest by researchers in animal behavior and human psychology.

This is because it stands somewhere between innate and learned behavior.

The imprinting theory of learning states that animals have an innate tendency to respond to certain external stimuli, creating behavior that is important to the survival of the individual and the species.

Lorenz was not the first to describe or name the behavior known as imprinting.

However, he went further than previous researchers by laying out its defining characteristics and generating interest in further study.

Lorenz raised half a set of goose eggs in an incubator, and left the other half with their mother.

When the incubated eggs hatched, the goslings followed Lorenz as if he were their mother, while failing to recognize their real mother.

As adults, they preferred the company of humans to geese, and would not mate with their own species.

Lorenz suggested that imprinting differs from other types of learning in two important ways: it takes place during a critical period−a window of time in which the learning can occur−and is irreversible once it has happened.

He also proposed that its effects continue in adulthood, leading to the choice of a mate from the same species as the mother.

Later research has expanded on and modified Lorenz’s findings.

Imprinting is now known to affect not only birds, but other species, including mammals and even fish.

It turns out that salmon learn how to return to their home stream to lay eggs after spending their lives at sea by imprinting on the stream’s unique smell.

Imprinting was originally thought to take place early in life, but it is now recognized also in adults, with critical periods of varying lengths.

Just as baby birds imprint on their mother, adult birds imprint on their chicks: during the critical period of nesting, parents will adopt chicks of foreign species introduced into their nest, even though they would kill and eat a strange chick at other times.

Also, studies have found that imprinting is not necessarily irreversible, especially in adults.

Some birds raised with a foreign species during the critical period of youth preferred to mate with those foreigners, but eventually switched to mating with their own.

Songbirds imprinted with songs from other species that they learn from tape recordings eventually start singing their own species’ songs if they hear it from live birds another case where imprinting is modified by experience.

ln humans, we know there is a critical period for learning speech.

Additional languages are learned most easily during childhood, but adults can also learn them with extra time and effort.

Some psychologists believe that imprinting is just another example of learned response to a new stimulus, as when a cat learns to come running at the sound of its feeding bowl being picked up.

The term is now used loosely to refer to many types of learning.

Imprinting continues to be a subject of interest for its possible applications in human developmental psychology, social pathology, and even philosophy.

Lorenz himself suggested that emotional problems in humans might be somehow related to imprinting in childhood.

Many books of advice on parenting emphasize the importance of newborn “bonding” with mother or father figures.

For centuries, people have debated “nature versus nurture.”

This questions how much of who we are is due to genetics and how much to environment.

The only agreement seems to be that most behavior falls somewhere in between.

Lorenz’s geese were born with the tendency to follow the first thing they saw, especially if it made a sound.

But they had no tendency to recognize their own mother or even their own species.

Many years after it was first described, imprinting continues to fascinate psychologists.

It focuses attention on the mysterious interaction between what we are born with and what the world provides.