Principles of Behavior Modification and Treatment

Habituation

Spontaneous Recovery

Dishabituation

Conditioning

Reinforcement

Stimulus and Response Generalization

Aversive Conditioning/Punishment

The most commonly used behavioral techniques include habituation, extinction, desensitization, counterconditioning, and shaping. Flooding is often talked about but seldom used because it has the potential to make most animals worse. While it is claimed that punishment is frequently used, with varying degrees of success, few people correctly employ punishment. For punishment to occur, the aversive stimulus (eg, screaming at the dog, startling the cat with a loud noise, etc) must occur sufficiently close to the onset of the behavior that the probability of the behavior occurring in the future is lessened. Most aversive stimuli are inappropriate in context, duration, or time of application and are more about the client’s anger than about changing the behavior.

Most of the humane, passive, or positive techniques involved in behavior modification are not hard to learn and are equally successfully employed as preventive techniques. The following is a short review of the basic principles involved in the techniques and their associated strategies.

Habituation:

Habituation is an elementary form of learning that involves no rewards. It is merely the cessation or decrease in a response to a stimulus that results from repeated or prolonged exposure to that stimulus. The stimulus can be positive, neutral, or negative. For example, horses placed in a pasture bordering a road may at first run away when traffic passes, but eventually learn to ignore it. As would be expected, stimuli associated with potentially adverse consequences are more difficult to extinguish with habituation than other stimuli. In prey species, responses to sounds associated with predators should be difficult to habituate because they have been selected for and generally are adaptive; the predator does not have to be present very often for the response to be rewarded. Furthermore, if such responses are even occasionally rewarded, the habituation response will be inhibited. In such circumstances, prolonged exposure to the stimulus may be associated with hypervigilance, exhaustion, and increased anxiety. In fact, this is one explanation for the feedback between anxiety and environmental events, even in situations when the anxiety is pathologic and potentially maladaptive.

Spontaneous Recovery:

This phenomenon is associated with habituation. If there is an extended interval between the time the animal last experienced a stimulus to which it had habituated and re-exposure to the stimulus, the animal may again react. Habituation usually occurs more rapidly following spontaneous recovery if no overt fearful associations are involved.

Dishabituation:

Dishabituation is the reinstatement of a habituated response as a result of exposure to a stimulus that provokes a response similar to the original. The classic examples of this involve mildly fearful responses—if habituation had just occurred to a certain hand gesture, and another movement occurred that was also worrisome for the animal, the animal could dishabituate to the hand gesture. Rehabituation is the rule unless the event is compounded and made more fearful, or the animal’s reaction is extreme (suggesting something innate about the animal’s response, not the event itself).

Conditioning:

Conditioning refers to associations between stimuli and responses. Classical conditioning does not require a reward structure to make these associations, while operant or instrumental conditioning uses a reward structure. In operant conditioning, learning is fastest if the positive reinforcer occurs immediately (within 0.5 sec). Delayed and intermittent reinforcements slow the acquisition of the response but work well to reinforce its maintenance. In addition to timing (quantity), value (quality) is also important—the more an animal values a reinforcer, the more quickly and reliably it will acquire the response. Hence, a food treat that dogs do not usually get (eg, cheese, boiled chicken, etc) will be better than their standard kibble in teaching them a new behavior. It is important to realize that not all dogs value food above all else—some prefer interactive play or petting.

Reinforcement:

Reinforcement is the application of a stimulus or an event that increases the probability that a certain behavior or class of behaviors will be repeated. A positive reinforcer is a stimulus or an event that occurs after a response that leads to an increase in the response in the future. A negative reinforcer is an aversive event or stimulus that increases the frequency of a behavior, but does so through escape or avoidance. Because people tend to use negative reinforcers in a way consistent with the potential for abuse, they should be avoided by those who feel less than absolutely confident in their timing and control.

Negative reinforcement is not to be confused with punishment. Punishment is the application of an aversive or negative stimulus after a response, which leads to a decrease in the frequency of the response. Negative reinforcement is the removal of an aversive stimulus that then leads to an increase in a response.

Second-order reinforcers are signals that can be used at a distance to convey that the reward or the valuable stimulus is coming. Commonly used second-order reinforcers are words (“Good girl!”), hand signals, and clickers or whistles. By carefully pairing these with the reward with which the response to the command has already been paired, second-order reinforcers can elicit the same response as the reward would (at least temporarily—suddenly switching from a first-order reward to only a second-order one should not be done without at least intermittent pairing of the first- and second-order rewards).

“Positive” training and “clicker” training have recently become fashionable. It is possible to do an excellent job at positive training without using any secondary reinforcers. Clicker training requires frequent practice and excellent timing. In situations involving problem behaviors, the animal must be confused as seldom as possible. The incorrect use of clickers may hinder, rather than expedite, a behavior modification program. However, the correct use of clickers is an excellent way to immediately “mark” desirable responses or to associate a positive emotional response with the stimulus. A competent trainer and clear and accurate instructions are therefore needed.

Stimulus and Response Generalization:

This occurs when an operantly or classically conditioned response is provoked not only by the object or event that originally provoked it, but by similar objects or events. A common example of stimulus response generalization in dogs is to people in uniforms: if a delivery person or meter-reader initially scared the dog or provoked a protective response, this response may then be generalized to others in uniform although the circumstances might not be the same. The more similar the original and subsequent stimuli are, the more similar the responses will be. Stimulus and response generalization may be associated with the development of profoundly anxious or fearful and phobic responses, and understanding this may be key to diminishing the worrisome behavior.

Extinction:

A response that ceases when reinforcement/reward is stopped is called extinction. A classic example of extinction of a response involves the dog that jumps up on people for attention. If people pet the dog, the behavior continues; if they stop at once and forever, the dog will eventually extinguish its response because the reward is no longer there. However, any form of intermittent reinforcement—even occasional petting of the dog in response to its jumping—will enhance the continuation of the response. The more valuable the original reinforcer, the longer the reinforcement has been continuing, and the more uncertainty there is about whether the response has been truly removed (ie, presence or absence of intermittent reinforcement), the greater the resistance to extinction.

Resistance to extinction can also occur even without reinforcement, if the reward was good enough and it is tightly coupled with the behavior. Because there is often an association between eliciting the reward and the intensity or rapidity of the performance of the behavior, the intensity or frequency of the behavior one is attempting to extinguish usually increases at the beginning of an extinction process. It is critical that clients not give in. Giving in will only make extinction more difficult because the animal has learned that although the client’s threshold has increased, the animal can override it.

Overlearning:

Overlearning is the repeated evocation and expression of an already learned response. It is a phenomenon that is frequently employed in training for specific events, but may be underused in preventing fearful responses in dogs. Overlearning accomplishes 3 things: it delays forgetting, it increases the resistance to extinction, and it increases the probability that the response will become a “knee-jerk” one, or response of first choice, when the circumstances are similar. This last aspect can be extremely useful in teaching an animal to overcome a fear or anxiety.

Shaping:

This learning technique works well for animals that do not know what response is desired by the trainer. Shaping works through gradual approximations and allows the animal to be rewarded initially for any behavior that resembles the desired behavior. For instance, when teaching a puppy to sit, following a slight squat with a food reward will enhance the probability that squatting will be repeated. This squatting behavior is then rewarded only when it becomes more exaggerated, and finally, when it becomes a true sit.

Avoidance:

Avoidance is essential until clients can seek qualified help, particularly in the case of aggression. With treatment it may be possible to desensitize the dog to circumstances in which aggressive behavior is exhibited, but avoidance is key in minimizing danger. Clients may be concerned that avoidance means that the dog will now have control, ie, that they are giving in to the dog. This is not what is happening; rather, the dog is not being given the chance to exert control in the manner to which it is accustomed. Every time a dog becomes aggressive, it learns that aggression may help it cope with the situation, thus reinforcing the problem. Even if the event is eventually aborted by an outside force, they learn the experience of exhibiting aggression.

Desensitization:

Desensitization is a decrement in response that is produced by gradual exposure to a stimulus that elicits the response. For example, if a puppy has become fearful of or stimulated by the doorbell, use of a tape recording of the doorbell could help stop the undesired response. If the tape is played very softly at first and then only gradually increased in volume at increments designed to elicit no response, the puppy may become desensitized to the doorbell.

In counterconditioning, negative or undesirable behavior is extinguished or controlled by teaching the animal to do another behavior (preferably favorable and fun) that competitively interferes with the execution of the undesirable behavior. This is best coupled with desensitization. In the doorbell example, the puppy will learn faster if it is first taught to sit, stay, and relax in exchange for a treat. The puppy must be absolutely quiet and calm, and convey by the look in its eyes, body posture, and facial expressions that it would do anything for its owner. Once this behavior is learned, the desensitization component is added by playing the tape recording at gradually increasing volume. Performing the adoration act for a food reward is incompatible with or competitively exclusive of barking. If at any point the puppy starts to act anxious or to not attend to the client, the tape recording should be lowered in volume until it can relax again. Relaxing is the key—the sitting and staying is merely a facilitator for the relaxation. There is no point in having the dog sit and stay if it is clearly distressed. Relaxation is the first step to changing the behavior.

Counterconditioning coupled with desensitization is an extremely time-consuming technique. The exercises must be constantly repeated so that the response lessens until there is none, and all the patient’s communicatory signals must be considered. Clients who are least successful with this technique want both quicker fixes and less work. However, moving too quickly provokes anxiety and sabotages any behavior modification program.

Flooding:

Flooding involves prolonged exposure at a level that provokes the response so that the animal eventually gives up. This is exactly the opposite of the approach taken in desensitization. It is far more stressful than any of the other therapy strategies and, used inappropriately, could damage the animal. The most common side effect is enhanced fear. This technique should be used only by those with extensive experience and as a last resort.

Aversive Conditioning/Punishment:

This strategy involves the presentation of an aversive stimulus in response to an inappropriate or undesirable behavior; the stimulus is intended to abort the behavior and to decrease the probability of it occurring in the future (the correct definition of punishment). To be most successful, the stimulus designed to abort the behavior must occur as early as possible but certainly within the first 30-60 sec of the onset of the behavioral sequence, and it must be consistent and appropriate. The critical factors in punishment include timing, consistency, appropriate intensity, and the presence of a conditioned response (ie, when the undesirable behavior ends there must be some favorable stimulus or reward, even if it is just praise or a pat). This is the most frequently ignored part of therapy for people whose pets have behavioral problems. People often resort to physical punishment as the correction method of choice, but punishment does not need to be physical. Furthermore, “good” punishment is just as hard work as appropriately executed counterconditioning and desensitization. Punishment is never an “easy out” and has a high probability of failure unless the client understands that its focus is to decrease the probability of future inappropriate events.