Concept of Learning, Instinct, Habituation, Imprinting, Reinforcement, Conditioning, and Temperament Scoring
27.4.1 Learning
Learning is a process whereby an individual acquires new responses and new capacities. Learning results in behavioral changes within an animal’s lifetime which can introduce a new dimension into behavioral evolution.
Behavior can have a genetic basis and so change occurs by natural selection operating on inherited mutations, favoring those changes in which the interactions with the environment lead to greater success. An animal which grows up in a persistent social group or has frequent contact with others is influenced by them and it will profoundly affect the way its behavior develops. The parent and the other adults in a social group form a constantly changing set of “models” from which young animals learn. Learning from others and copying can be a potential factor for change in behavior, which is both rapid and extensive. The famous long-term studies on Japanese macaques (Macaca fuscata) have recorded the development of a “food-washing” culture in some groups. It might have originated in some monkeys copying humans who were providing them with sweet potatoes after washing the earth sticking to sweet potatoes. Later on, it could be observed that due to social learning, some coastal groups of monkeys also began to wash food in streams.Learning as a whole helps the animal to survive better in ever-changing environment. Animals learn about potential mates, familial relationships, aggression, and about predators, e.g., prey often in areas that contain both predatory and nonpredatory species. Encounters with predators are not the same always, as at any given time, some predators might be in hunting mode while others might not be actively hunting the prey. If prey can learn to distinguish between dangerous and benign encounters with potential predators, they may free up that time for their other vital activities such as foraging or mating.
Learning and memory formation are important to both wild and domesticated animals. Dogs and horses are often valued based on their ability to learn. In farms, the cows learn to approach the milking area, feeders and also remember which cow will butt her. Pigs and poultry learn to operate electronically controlled feeders and drinkers. Many animals learn to fear veterinarians who are easily recognizable by their white coats and their shiny examination tables.
Learning occurs in two distinct phases: short-term memory which is a synaptic event wherein impulses pass from one neuron to another due to sustained neurotransmitter release and long-term memory which requires new protein (cAMP response element binding protein) synthesis. These proteins form new synaptic connections which are the basis for longterm memory. The cellular and molecular mechanisms for learning are similar throughout various species ranging from fruit flies to large mammals. The hippocampus appears to be essential for explicit spatial learning, but the striatum is necessary for tasks that require incremental learning of associations. For learning simpler implicit tasks such as the classical conditioning of blinking when a puff of air is directed at the eye, only the cerebellum is necessary.
27.4.2 Instinct
Instinct is a stereotyped, species-typical behavior that is fully functional for the first time it is performed, without the process of learning. Such behaviors are usually triggered by a particular stimulus or cue and are not readily modified by subsequent experience. For instance, a kangaroo rat instantly performs an automatic escape jump maneuver when it hears the sound of a striking rattlesnake, even if it has never encountered a snake before. Instinctive behaviors play an essential role in survival. Instinct develops along with the developing nervous system and gradually evolves over the generations to match an animal’s behavior to its environment. Instinct behavior does not essentially require learning or practice, but it is needed for those who appear appropriately the first time.
Animals may not have any pre-set responsiveness but tend to modify their behavior on the basis of their individual experiences. They learn how to behave appropriately and perhaps practice or even copy from others to produce the best response. Pre-set behavior which requires no learning or practice is especially advantageous for animals having short life span and no parental care.27.4.3 Habituation
Habituation is an extremely simple form of learning, wherein an animal, after a period of exposure to a stimulus, stops responding and ignores it. Habituation occurs after repeated exposure. Habituation is more if the stimulus is not offensive or harmless. Lack of continued response to strong odors is a common example of sensory habituation. Habituation to complex stimuli may occur at the level of hippocampus in the brain. Habituation helps in filtering the large amounts of information received from the surrounding external environment. By habituating to less important signals, an animal learns to focus its attention on the most important features of its environment. For example, birds very soon learn to ignore the scarecrow which had scared and made them fly away when it was initially placed in a field and later the birds get habituated to it. Thus, habituation can be considered as a simple form of learning. It is relatively long-lasting and is “stimulus-specific,” i.e., only the stimuli which are repeated without reinforcement are affected whereas the animal remains alert to others.
Another good example may be observed in species that depend on alarm calls to convey information about approaching predators. As the animal gets habituated, the animals stop giving alarm calls when they become familiar with other species in their environment that turn to be non-predators.
27.4.4 Imprinting
“Imprinting” refers to the various behavioral changes wherein a young animal becomes attached to a “mother figure” and/or a future mating partner. This type of response to a mother figure is usually called “filial imprinting.” Imprinting is distinctive because it occurs soon after hatching or birth and commonly results in an attachment which is difficult to change.
Imprinting is an early form of learning having major effects on how young birds and mammals attach to a parent figure which offers protection, and interestingly, rather later may influence the young animal’s choice of a sexual partner. Imprinting-like phenomena are also associated with the social development of mammals. For example, the popularly known example is of baby ducks and geese, which are observed to closely follow their mother on their early forays away from the nest. The baby birds form an attachment to an individual that was present as they hatched out and moved about after hatching.27.4.5 Operant Conditioning
Learning in which behavior is affected by its consequences is called as operant conditioning. This type of learning is seen in animals as they associate performing a specific behavior with some sort of benefit or detriment. Operant conditioning is classified as a type of associative learning. When behavior is followed by something the animal wants the behavior gets strengthened. Conversely, if the behavior is followed by something the animal fears or dislikes the behavior is likely to weaken also in cases where nothing follows the behavior. Operant conditioning is useful when the animals are trained to perform behaviors, as it primarily deals with voluntary behavior.
Operant conditioning continues throughout the animal’s life. They learn through trial and error about the behavior that brings them stimuli they want and which brings them stimuli they dislike. The stimuli affecting the animal’s behavior can be a variety of foods, touches, sounds, activities, and odors. It depends on the individual animal whether a stimulus is a reinforcement or punishment. Both reinforcement and punishment must occur within 2 s of the behavior and before the performance of the behavior or else their effect on the behavior is likely to be weakened tremendously.
27.4.6 Reinforcement
The treat given for exhibiting behavior during operant conditioning is called as reinforcement.
There are two types of reinforcements used in operant conditioning: positive and negative reinforcements. Positive reinforcement involves adding a stimulus, the animal wants immediately after or during the behavior it is performing. Adding this stimulus strengthens the behavior that precedes it. Rewarding the dog a piece of bone whenever it obeys the owner’s command would serve as positive reinforcement. Negative reinforcement takes away a stimulus when a behavior happens, causing the behavior to strengthen. For example, when a dog lunges at the approaching person causing the person to back up, the animal learns lunging behavior removes the scary person. Consequently, the behavior of lunging at the person will strengthen.27.4.7 Classical Conditioning
This type of associative learning is the one in which an animal associates a novel stimulus with another stimulus that has already caused a reaction. After repeated pairings, the novel stimulus will also cause the same reaction. The typical pattern for classical conditioning is the animal associating a conditioned stimulus with an unconditioned stimulus to elicit an unconditioned response. Again, after many pairings, the conditioned stimulus will elicit a conditioned response. A conditioned stimulus is often defined as a stimulus that initially fails to elicit a particular response but then comes to do so when it becomes associated with a second (unconditioned) stimulus.
The conditioned stimulus must occur before an unconditioned stimulus to elicit the unconditioned response as the animal is learning about the conditioned stimulus. The unconditioned response occurs naturally after the unconditioned stimulus but the conditioned response is learned when the conditioned stimulus repeatedly precedes the unconditioned stimulus. This type of learning was studied by Russian Ivan Pavlov in the late 1800s and the early 1900s. His experiments with dogs involved the reflex of salivation. Most of the behaviors involved are involuntary; they include reflexes, emotions, and secretions.
Classical conditioning is powerful as learning takes place within the unconscious mind. For example, a cat learns being put in its carrier signifies it is taken to the veterinary hospital. Once when it is placed in the carrier, it starts to feel as if in the hospital. In a way, the carrier becomes the hospital for this cat. We can effectively use classical conditioning to our advantage by teaching animals to associate the hospital and/or the carrier with stimuli they enjoy.27.4.8 Spatial Learning
Spatial learning is the ability to recognize surroundings and memorize a route. In contrast to other forms of learning, it is probably explicit, i.e., the animal is aware that it is learning.
27.4.9 Temperament scoring
The temperament of an animal influences the animal’s judgemental capabilities about the surrounding environment. If the animal is highly reactive and fearful, it will judge more stimuli to be dangerous and thus will become sensitized to them. Although the animal’s temperament is largely present at birth, it can and is modified throughout life by experience. During an animal’s socialization period, they can be exposed to many stimuli, creating a board basis of exposure to many objects, experiences, sounds, and living things. This allows them to have the best chance of being able to habituate to the stimuli commonly found in their environment throughout their life.
Hormones also influence learning and temperament. Glucocorticoids have a major role in mediating stress responses and learning in animals. In adult animals, glucocorticoids easily cross the “blood-brain” boundary and bind with the receptors in the hippocampus, where they can modulate the emotional state and cognitive abilities of the individual. Glucocorticoids not only influence learning and memory in adult animals but also have an influence on fetus. For example, when pregnant female rats are stressed and level of glucocorticoid rises, the offspring of such females show high levels of anxiety and perform sub-optimally in learning tests indicating that stressing pregnant mothers affects anxiety levels in their offspring.
27.4.10 Culture
Extensive observation of social groups in nature commonly reveals enduring differences in their behavior. Individual patterns have arisen in one group or another and persist because young animals acquire them from the adults with whom they grow up. These persistent behavioral features are referred as “culture” and the changes as cultural evolution. They are acquired and passed on across generations/between individuals. Cultural evolution is possible only among animals living in contact with others and having the ability to modify their behavior by copying and practicing. For example, rats have been shown to acquire the tendency to dig for hidden food by watching others doing so. Having learnt this, they themselves can become models from whom others learn thus initiating a chain of cultural transmission. Cultural transmission may occur via vertical (information is transmitted across generations from parent(s) to offspring), oblique (transfer of information across generations via unrelated individuals, but not through parent/offspring interactions), or horizontal (transfer of information between individuals of same age groups) transmission.
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