habit-strength = (th, bt) Hull's 8Hr. A hypothetical or inferred ''historical" variable considered to determine the extent to which a conditioned stimulus or set of stimuli tends to evoke a given response. A function of the number of reinforcements, of the quantity of the reinforcing stimulus, and of time variables. For a full development, see Hull (16).
habituation = 1. (emp) the decrement in response-strength which occurs with the repeated elicitation of that response in massed practice. In reflex habituation, recovery after a time interval may be complete, although on subsequent occasions habituation may occur more rapidly. Operationally, there is no distinction between habituation and extinction, except in terms of the history of the response prior to the procedure of repeated elicitation. Responses that are extinguished have previously undergone a systematic experimental procedure of reinforcement before repeated elicitation or emission without reinforcement begins. The antecedent history of responses that are habituated out shows no such experimental reinforcement. As data accumulate, it may become advisable to distinguish between several kinds of response decrements that are all functions of repeated elicitation, but differ with respect to stimulus-control and rate of recovery. See, for example, definition 2. =2. (emp, eth) response decrement that is a function of the number of elicitations, that is specific to the response (and independent of the stimuli eliciting it), and from which recovery is slow or absent. Hinde (12, 13, 14).
hierarchy = (th, eth, bt) a series divided or classified in ranks or orders. This term is used by psychologists and ethologists to describe certain conspicuous properties of behavior. "Habit-family hierarchy" and "hierarchical organization of centers" both refer to such organizations of hypothetical entities or constructs postulated to account for certain temporal sequences and dependent probabilities evident in behavior. The term is also applied empirically to behavior, where it has reference to certain statistical sequential dependencies that can be found in the order in which a number of responses occur, and theoretically to sets of causal variables inferred from the statistical organization of behavior.
hypothesis = 1. (emp, bt) a term applied to repeated occurrences of the same response or response-pattern during the acquisition of a discrimination in the two-choice discrimination experiment (see Lashley jumping-stand) when a large proportion of the responses are errors. Alternation and position habits are hypotheses. = 2. (?, bt) a class of expectancies postulated by cognitive theories to account for hypothesis (1.) According to continuity theory; hypotheses are the effect of the summed differential reinforcements of response to various aspects of the discriminative stimuli. = 3. (emp, bt) one class of statements emitted by humans when they are undergoing discrimination or concept formation training. An hypothesis may be distinguished from other such statements in that it purports to describe the rules or principles followed by the experimenter in reinforcing the subject. If it indeed does describe these rules, it will be regularly reinforced on each occasion that the behavior it controls occurs, without regard to the particular discriminative stimuli present on that occasion. If, however, the experimenter is interested in human hypothesizing, he may independently reinforce the hypotheses and the behaviors they direct. A discriminated hypothesis is often termed "conditional." =4. (th, bt) an hypothesis (3.) that is inferred to occur covertly, when subjects are be-having in discrimination situations as they do when such hypotheses do in fact occur. A very dangerous inference; cf. hypothesis (1.).
imprinting =1. (emp, eth) the operation of visually presenting to an individual large (and usually noisy) moving objects (exclusive of members of its own species) during the first hours of its life. Imprinting is said to have occurred if, and only if, the individual subsequently exhibits toward the large moving object (and objects like it) the behavior ordinarily exhibited only to-ward members of its own species. By extension, theoretically, the term is then applied to such behavior shown with respect to its own species. The experimental data at hand do not yield a more adequate empirical definition. =2 (th, eth) a process hypothesized to account for imprinting (1.) in terms of perceptual theory. = 3. (con) any learning that strikes someone as 'like' imprinting (1.).
inertia = (emp, eth) continuation of a response after the stimuli for it are withdrawn. Cf. After-discharge.
inhibition = 1. (th, bt) a hypothetical state of the animal sometimes used to account for decrements in response magnitude, or habit-strength, or both. It is a negative, variable presumed to operate by canceling out an excitation of some sort. =2. (th, physiol) a cortical process opposite to excitation and postulated as having the property of suppressing excitation and, hence, of suppressing the behavior dependent on that excitation (20). Its behavioral correlate in the extreme case is inactivity and eventually sleep. =3. (th, eth) a block.
inhibition/external = (emp, eth) the term applied to the fact that, in the course of the acquisition of a conditioned response, if an extraneous, stimulus is presented with the conditioned stimulus, a CR of smaller magnitude than that predicted from previous trials may be produced.
inhibition/reactive = (th, bt) Hull's Ir (16). A hypothetical state variable which, together with conditioned reactive inhibition, accounts for response decrement in both learned and unlearned behavior (i.e., for both extinction and habituation). It is a function of the work involved in a response, of the number of times the response is elicited, and of time since the occurrence of the last response. It applies particularly to the ease of short-term reversible decrements. i
inhibition/conditioned reactive = (th, bt) Hull's 8Ir (16). A hypothetical state variable which, together with reactive inhibition, accounts for response decrement. It is a function of I' and of some of the variables that control habit-strength, and is used to account for long-term, relatively irreversible decrements. When a response is extinguished, 1r increases and becomes conditioned to the stimuli present. On subsequent occasions, when the stimuli are again presented to the animal, the stimuli elicit 8Ir at the same time that further Ir produced by the repeated elicitation of the response. 1r and 81r summate to render ineffective 8Hr or 8Ur for the elicitation of the response.
innate = (emp, genetics) a term applied to differences in genetic character between two members of the same species that have been raised in the same environment. It is now generally acknowledged that the term innate, a technical one in genetics, cannot properly be applied to behavior as synonymous with unlearned or inborn, and its use in this sense may be expected to become less frequent. Where it has appeared in the past, innate behavior should now be read as unlearned behavior or as species-specific behavior. The restricted use of the term innate has recently been adopted as necessary by prominent ethologists. Its new place in the technical vocabulary of ethology and of behavior theory, and the use of species-specific and unlearned instead, will probably have fruitful consequences, since the connotations of innate for ethologists and psychologists have been different indeed and have led to many confusions that may now be avoided. (E.g., one of two human beings has blue eyes, the other has brown eyes. Blue eyes are not innate. Brown eyes are not innate. But the difference in eye color between the two persons is innate. Clearly, by this definition, which is that of the geneticists, it is not permissible to speak of a response, or set of responses, as innate.)
insight = 1. (emp, lab slang) a gross difference in behavior between two successive occasions on which behavior can occur, when the behavior shown on the second occasion is close to what the experimenter has previously decided upon as a "good" or "efficient,'' solution. =2. (con) an event hypothesized to account for insightful learning. It may be further defined as "reorganization of the perceptual field" or the "apprehension of relations," for which the writer cannot find any elucidating elucidations.
instinct = 1. (emp) a class of sets of responses shown by most members of a species. Many of the responses can be demonstrated as dependent on highly specific stimuli in the environment. Such a class is empirically demonstrated by showing that certain responses are statistically organized (i.e., associated together in time) under specified environmental conditions and following a single set of drive operations, when there have been experimental manipulations calculated to prevent learning. =2. (emp, eth) same as instinct (1.) but without any qualification with respect to experimental manipulations calculated to prevent learning. Such a definition has recently been proposed by Tinbergen (30). It is based on the increasing emphasis on the logical (and experimental) impossibility of distinguishing in a meaningful way between "1earned" and "unlearned" behavior, and recognizes that this distinction, even if it could be made easily, would not necessarily be a useful one. Theoretically, this concept of instinct may readily be related to the biological concepts of function and adaptation as they appear in general evolutionary theory. = 3. (th, eth obsolet]) a hypothetical system of hierarchically organized centers postulated to account for observable instances of instinct (1.). "A hierarchically organized nervous mechanism which is susceptible to certain priming, releasing and directing impulses of internal as well as of external origin, and which responds to these impulses by coordinated movements that contribute to the maintenance of the individual and the species" (29).
intention movement = (emp, eth) if an instance of a response that is a member of a behavior chain occurs usually, but not necessarily, in association with instances of other members of the same chain, it is termed an intention movement with respect to later members of the chain. Used most often when the chain is not necessarily carried through to completion immediately. Intention movements are usually of low intensity. See response/intensity of. The experienced observer can predict accurately from the occurrence of intention movements that the chain will be carried to completion after a delay or that it will begin anew. For example, members of a species of bird will give an ordered series of responses before becoming airborne. From these responses, termed intention movements of flight, the observer can predict, other things being equal, that the bird will take off in the very near future. The responses can be identified on occasions when they are not followed by flight in young birds that have never flown or in birds that are presented with weakly aversive stimulation while they are feeding. Cf. vicarious trial and error and conflict.
interference = (th, bt) a process often assumed by contiguity theorists (see theory/contiguity) to underlie experimental extinction, involving a decrement in response-strength as a result of the occurrence and conditioning of competing responses. This view implies that habituation and extinction are produced by the same variables that produced acquisition of the response that is undergoing decrement. This process is a basic postulate of contiguity theory. See also conditioning/counter-.