Abnormal Behavior

These activities show dysfunction in action and behavior. Alternatively, the terms behavior pathology or behavior problems might be used. By comparison, many behavioral complaints are normal behaviors that are undesirable to owners (eg, garbage raiding, jumping up, predation, herding, guarding).

Aggression

Aggression can be defined in a narrow sense (attack) or in a broader sense as agonistic behavior. In the latter case, aggression can be appropriate or inappropriate, in-context or out-of-context, inter- or intra-specific, or a challenge or contest that results in deference or in combat and resolution.

Anxiety

Anxiety is the apprehensive anticipation of future danger or misfortune, which may be accompanied by both behavioral and somatic signs (vigilance and scanning, autonomic hyperactivity, increased motor activity and tension).

Compulsive or Obsessive-Compulsive Disorders

Compulsive disorders may arise out of anxiety, conflict, or frustration. Unlike displacement activities, compulsive behaviors are exhibited independent of the original context, have no apparent goal, and have an element of dyscontrol in either the initiation or termination of the behavior. They may be repetitive, exaggerated, sustained, or so intense that they might be difficult to interrupt. There appears to be a genetic predisposition to the development of certain compulsive behaviors (eg, wool sucking in oriental breeds of cats, tail chasing in German Shepherds, flank sucking in Dobermans). Compulsive disorder or obsessive-compulsive disorder is a diagnostic term indicating behavioral pathology that often improves with psychotropic medications that inhibit serotonin reuptake. However, there can be a wide range of presentations (eg, locomotor, self-trauma, hallucinatory) and multiple neurotransmitters have been implicated (eg, dopamine, β-endorphins). This may indicate an altered course of disease over time or that the diagnosis encompasses more than one disorder.

Conflict

Conflict arises when a pet has competing motivations or is motivated to perform more than one opposing behavior. This might occur when a dog is motivated to greet but is fearful of approach perhaps because of previous unpleasant experiences (eg, yelling, hitting, pinning). The resultant behavior might be either a displacement behavior (see Behavioral Medicine Introduction: Displacement Behavior) or aggression (when fear is an overriding factor).

Displacement Behavior

This type of activity is performed out-of-context, or is “displaced,” because the animal is unable—physically or behaviorally—to execute another activity or otherwise occupy itself. This is less specific than redirected behavior (see Behavioral Medicine Introduction: Redirected Behavior), in which the intended behavior is directed toward another target. When displacement activity occurs, the behavior may be out of context with the situation (eg, circling, air snapping, or even urination). Displacement behaviors may arise from conflict or frustration or be a vacuum activity.

Dominance

Dominance is a concept that has been frequently misapplied. The ethological concept of dominance refers to competitive control over a resource in a limited circumstance and to the ability of a higher-ranking animal to displace a lower-ranking one from that resource. Rank is usually defined by an ability to control the resource or by access and ability to restrict matings (eg, the alpha wolf pair generally is thought to do all the mating); however, extra-pair copulation is almost always more common when assessed by DNA analysis than it was believed to be on the basis of behavioral observations.

Dominance is not interchangeable with a hierarchical rank. Dominance ranks, particularly those that are linear and in which a “dominant” animal is identified, are largely artifacts of experimental or manipulated situations. A “dominant” animal is not the one engaged in the most fighting and combat. Most high-ranking animals seldom have to contest their right of access to a resource. Instead, high-ranking animals are usually better identified by the character and frequency of deferential behaviors exhibited by others in their social group, and their ability to respond appropriately to a variety of social and environmental circumstances.

Fear

Fear is a feeling of apprehension associated with the presence or proximity of an object, individual, or social situation. Fear is part of normal behavior and can be an adaptive response. The determination of whether the fear or fearful response is abnormal or inappropriate must be determined by context. For example, fire is a useful tool, but avoidance of fire is an adaptive response. If a pet is fearful of stimuli that are innocuous such as walking on certain types of surfaces or going outdoors, such fear would be irrational and, if it were constant or recurrent, probably maladaptive. Normal and abnormal fears usually occur as graded responses, with the intensity of the response proportional to the proximity of the stimulus. A sudden, all-or-nothing, profound, abnormal response that results in extremely fearful behaviors is usually called a phobia.

Frustration

This state arises when an animal is motivated to engage in a sequence of behaviors that it is unable to complete because of physical or psychological obstacles in the environment. When pets are frustrated—such as a cat that cannot gain access to an outdoor cat that it sees through the window, or a dog that cannot get to a stimulus on the other side of a door or fence—the resultant behavior can be a redirected behavior (eg, attack of another family pet or owner), a displacement behavior (eg, stereotypic pacing), or signs associated with anxiety (eg, whining or howling). Another example of goal frustration is the dog or cat that chases a laser light toy but is unable to finish the sequence or achieve any goal. This frustration may lead to obsessive chasing of other lights and shadows.

Phobia

Most fearful reactions are learned and can be unlearned with gradual exposure. Phobias are defined as profound and quickly developed fearful reactions that do not diminish either with gradual exposure to the object or without exposure (as fears will) over time. Phobias involve sudden, all-or-nothing, profound, abnormal responses that result in extremely fearful behaviors (catatonia, panic). An immediate, excessive anxiety response is characteristic of phobias. Phobias may develop over time—some animals develop increasingly more intense fears with repeated exposure (eg, storm phobias). However, once established they are immediate and intense when the stimulus is presented. Once a phobic event has been experienced, any event associated with it or the memory of it is often sufficient to generate the response (eg, wind, rain, or darkening sky and storm phobias). While fears may diminish with repeated exposure and no untoward consequences, phobias can remain at or exceed their former high level for years even without re-exposure. The genesis for such events in dogs is usually either extremely frightening or traumatic, or the dog itself has profound internal problems with fear (eg, genetic predisposition) so that responses to unfamiliar stimuli are excessive. Owner responses might inadvertently reinforce fearful and phobic behaviors or if unpleasant or negative (eg, frustration, punishment) could further enhance the pet's fearful emotional state. Phobic situations are either avoided at all costs or, if unavoidable, are endured with intense anxiety or distress.

Redirected Behavior

These activities are directed away from the principal target and toward another, less appropriate target. When the animal is in a state of emotional arousal and is unable to reach the appropriate target, the behavior can be redirected to an alternative target if the animal is interrupted.

Stereotypic Behaviors

These behaviors involve a repetitious, relatively unvaried sequence of movements that has no obvious purpose or function but is usually derived from contextually normal maintenance behaviors (eg, grooming, eating, walking). Not all stereotypic behaviors meet the diagnostic criteria for compulsive or obsessive-compulsive disorders (OCD), while most compulsive and OCD involve stereotypic behaviors. A stereotypy is a nonspecific sign and a description—not a diagnosis.

Vacuum Activity

Such activity involves an instinctive or unconscious response in the absence of the stimulus that would normally elicit that behavior. The activity seemingly has no apparent, contextual, useful purpose.

Last full review/revision March 2012 by Gary Landsberg, BSc, DVM, MRCVS, DACVB, DECVBM-CA