ETHOLOGY NOTES-LEARNING AND TYPES OF LEARNING

Learning

Learning is the acquisition of information. Memory is the storage of effects, impressions and information’s gained through learning and their subsequent retrieval on demand. They are the results of activities of nervous system. Some were in the nerve system there is a permanent record of the information gained through learning called engram or memory trace.

Learned behaviour is the pattern of behaviour gained in life through experience and the interaction with environment. Learning and learned behaviour are related to changes in the readiness of neurons to form synapses and circuit relationships with each other. The existence of neuronal circuitry is a pre requisite for learned behaviour. The degree of performance of learned behaviour mostly depended on memory.

Types of Learning

Different types of learning exhibited by animals are: habituation,conditioned reflex (classical conditioning),trial and error learning (instrumental conditioning), latent learning, insight learning, imprinting.

Habituation

Habituation is the simplest type of learning. Habituation is the learning by an animal not to respond to a stimulus. Habituation involves not the acquisition of new responses but the loss of old ones.  It is the reduction of responsiveness that is of no use or harm to the life of the animal. This is the case where, upon repeated exposure to a stimulus, the animal gradually decreases its natural response until it may vanish entirely. For example if an animal is exposed to a moderate sound, its initial response will be very high and it will orient toward the sound. But with each successive exposure, its orientation to the sound stimulus becomes less and less until it orients no longer. In a sense, habituation represents the dropping out of responses, which are of no ‘significance’ in the life of the animal. This has great adaptive significance. Every time when the animal responds to a stimulus it is expending energy. Habituation is a means by which an animal can conserve energy by not responding to stimuli, which have no apparent significance in s life.

Conditioned reflex ( Classical conditioning )

These are complex uninhabited and learned or acquired cranial reflexes, evolved in life time of an animal. They result from experience and memory. They are elaborated in the life time of animal with formation of temporary nervous connections and with the use of highest centres of central nerve system. Conditioned reflexes result in response to an indifferent stimulus, called conditioned stimuli. Conditioning is the previous association of native reflexes with indifferent stimuli (which forms the temporary nerve connections). Biological significances of conditioned reflex involves the following,

1.   Ensure adaptation of organisms to the external environment in the course of life,

2.   Enable better orientation in changing conditions,

3.   Play an important part in the physiology of learning,

4.   Helps animals to find food, to avoid danger and to avoid harmful influences.

Latent learning

Latent learning is the learning in animals through the exploration of new circumstances and surroundings for later use in their life. There for called as exploratory learning. It is a kind of pre-adaptation for a life in later stage. The acquired information’s remains latent or unexpressed for a time in life, hence it has the name. Latent learning increases the fitness and survival value of organisms. Animal learns new information’s when environment changes (stimulation). This acquired information’s can be useful at a later stage when the environment changes again. .   For example a non-hungry rat was allowed to explore a maze for ten days. During this time the animal learned several things, but they remained latent. On the eleventh day it was made hungry. The animal could found out the food placed at a particular end of the maze quickly.  On the other hand if the animal had not given an opportunity to explore the maze previously it could not have reached the food so quickly. Here the learning during the previous exploration (though remained latent) helped the animal. Thus latent learning is a type of learning which involves an animal using experience gained at one time in the modification of behaviour at a much later time.

Insight learning

Insight appears to be the highest form of learning. In this learning the animals learns how to solve a complex problem easily and quickly. It is very prominent in humans, primates and mammals but rare in invertebrates. Insight learning probably is the highest type of learning based on information’s previously gained through other types of learning. It relies more on mental abilities such as thought and reasoning.

E.g. in Kohler experiment chimpanzee reach banana dangling from ceiling by placing boxes one above the other.

Imprinting

It is a simple and species specific rapid learning behaviour that occurs during a critical receptive period in early stages of life. In it the young animal learns to direct its social responses to a particular object, usually a parent. It takes place only during a critical period in early life, if it not takes place in that time, it will not occurred any time in future life. During this period social attachments are established and social customs are registered in the brain as engram. Imprinting is irreversible so that the learned behaviour becomes almost fixed and resistant to change. Imprinting is significant in that it establishes a bond between the offspring and the parents, particularly the mother in many birds and mammals. This enables the offspring to acquire the skills of parent. The term was coined by Konard Lorenz, to describe the behaviour he discovered in ducklings of grey goslings, when deprived of their parents, very shortly after hatching, would follow the first moving object they see and use it as a substitute parent, ignoring real parents.