Bornstein, M. H., & Suess, P. E. (2000). Physiological self-regulation and information processing in infancy: Cardiac vagal tone and habituation. Child Development, 71(2), 273-287.

Investigated the role of physiological self-regulation (cardiac vagal tone) in information processing (habituation) in 81 infants. Nucleus ambiguus vagal tone (V-sub(na), a measure of respiratory sinus arrhythmia) was used to index cardiac vagal tone. Physiological self-regulation was operationalized as the change in V-sub(na ) from a baseline period of measurement to habituation. Decreases in V-sub(na ) consistently related to habituation efficiency, operationalized as accumulated looking time (ALT), in all infants twice at 2 mo and twice at 5 mo; however, this relation was accounted for by infants who met a habituation criterion on each task. Among habituators, shorter lookers also had greater V-sub(na ) suppression during habituation. Within-age and between-age suppression of vagal tone predicted ALT, but ALT did not predict suppression of vagal tone. Physiological self-regulation provided by the vagal system appears to play a role in information processing in infancy as indexed by habituation. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 4 of 16 in PsycINFO 1999-2000/12


Dielenberg, R. A., & McGregor, I. S. (1999). Habituation of the hiding response to cat odor in rats (Rattus norvegicus). Journal of Comparative Psychology, 113(4), 376-387.

Cat odor-induced hiding was examined in rats (Rattus norvegicus) using an apparatus with a "hide box" at one end and a piece of a worn cat collar at the other end. Rats spent most of their time hiding on exposure to the cat collar, but this response gradually habituated over repeated daily exposures. Hiding was reversed by administering the anxiolytic drug midazolam (0.375 mg/kg). Rats showed increased anxiety on the elevated plus-maze after exposure to the collar. This response was absent in habituated rats, suggesting that habituation of hiding reflects decreased odor-induced anxiety. It was established that rats located in the hide box of the apparatus might not have detected the odor of the cat collar placed at the other end of the apparatus. This implies that habituation occurs after relatively modest levels of odor exposure. Overall, the results cast some doubt on claims that predatory odors in rats are akin to phobic stimuli in humans. (PsycINFO Database Record (c) 2000 APA, all rights reserved)(journal abstract)


Fischer, H., Furmark, T., Wik, G., & Fredrikson, M. (2000). Brain representation of habituation to repeated complex visual stimulation studied with PET. Neuroreport: For Rapid Communication of Neuroscience Research, 11(1), 123-126.

To investigate CNS habituation (i.e., response decrement due to stimulus repetition) the present study used positron emission tomography (PET) to measure regional cerebral blood flow (rCBF) in eight healthy women (20-32 yrs old) during two repetitions of complex visual stimuli (viewing of snake and park scenes for 2 min during PET scanning). Repeated visual stimulation resulted in neural habituation bilaterally in the secondary visual cortex and in the right medial temporal cortex including the amygdala and the hippocampus. Regional CBF in the left thalamus was elevated as a function of repeated stimuli presentations. Thus, repeated presentation of complex visual stimuli result in rCBF habituation in later stages of the visual processing chain. The elevated neural activity in the thalamus might be associated with interruption of further neural transmission related to suppression of non-meaningful behavior. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 5 of 16 in PsycINFO 1999-2000/12

Jordan, W. P., Strasser, H. C., & McHale, L. (2000). Contextual control of long-term habituation in rats. Journal of Experimental Psychology: Animal Behavior Processes, 26(3), 323-339.

This study examined contextual control of long-term habituation and whether such effects are dependent on the habituating response system. Habituation of the acoustic startle response transferred from the home cage to the testing context, whereas habituation of lick suppression was context specific (Experiments 1 and 2). Contextual control of habituation was demonstrated between 2 experimental contexts for lick suppression to a tone (Experiment 3) and bar-press suppression to a light (Experiment 4). Experiment 5 extinguished habituation of lick suppression and the orienting response to a tone with 27 exposures to the habituation context. Context specificity of both responses also was found. Previous failures to demonstrate contextual control of habituation may be due to the choice of response system and to less sensitive procedures to detect response recovery. The habituation mechanism for startle is independent from the process or processes that underlie habituation in other response systems, but the nature of these mechanisms is not yet known. (PsycINFO Database Record (c) 2000 APA, all rights reserved)(journal abstract) Record 9 of 16 in PsycINFO 1999-2000/12


Kellman, P. J., & Spelke, E. S. (1983). Perception of partly occluded objects in infancy. Cognitive Psychology, 15(4), 483-524.

In 6 experiments, 224 3-4 mo olds were habituated to 1 object whose top and bottom were visible but whose center was occluded by a nearer object. They were then tested with a fully visible continuous object and with 2 fully visible object pieces with a gap where the occluder had been. A 7th experiment with 10 undergraduates investigated how infants' perception of partly occluded objects compared with that of adults. Patterns of dishabituation suggested that infants perceived the boundaries of a partly hidden object by analyzing the movements of its surfaces: Infants perceived a connected object when its ends moved in a common translation behind the occluder. Infants did not appear to perceive a connected object by analyzing the colors and forms of surfaces: They did not perceive a connected object when its visible parts were stationary, its color was homogeneous, its edges were aligned, and its shape was simple and regular. Findings do not support the thesis from gestalt psychology that object perception first arises as a consequence of a tendency to perceive the simplest, most regular configuration, or the Piagetian thesis that object perception depends on the prior coordination of action. Perception of objects may depend on an inherent conception of what an object is. (40 ref) (PsycINFO Database Record (c) 2000 APA, all rights reserved)(unassigned) (see page 554 of Gleitman, 1999)

Mather, J. A., & Anderson, R. C. (1999). Exploration, play and habituation in octopuses (Octopus dofleini). Journal of Comparative Psychology, 113(3), 333-338.

The combination of exploration, habituation, and exploratory play was investigated in octopuses (Octopus dofleini). Eight octopuses were given 10 trials to investigate a floating pill bottle. Exploration consisted of palpation of the object with the arms. Habituation was noticeable in the 1st trial but was more complex across trials. Two octopuses appeared to show exploratory play. This play consisted of aiming water jets through the flexible funnel, which caused regular transport of the object to and return by the aquarium intake current. In this situation, the amount of the 3 activities appeared to be minimally correlated. The results raise questions about the course of habituation, the definition and the extent of play, and the relation of exploratory play to exploration in complex animals. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 16 of 16 in PsycINFO 1999-2000/12

McNamara, F., Wulbrand, H., & Thach, B. T. (1999). Habituation of the infant arousal response. Sleep, 22(3), 320-326.

Examined whether the individual arousal responses would diminish serially and whether the brainstem responses may be more resistant to habituation than the cortical response. The effects of sleep on this process were also determined. 22 normal infants (aged 1-22 wks) were studied. The infants underwent polysomnographic monitoring during a daytime nap. Tactile stimuli was applied to the infants foot at 5-sec intervals. It was found that spinal, brainstem, and cortical responses occurred on the first trial of each test. Repeated trials during non-REM and REM sleep resulted in a decrease in the incidence of each individual response and eventually elimination of the arousal responses. Cortical responses were eliminated first, followed by brainstern responses and finally spinal responses. The elimination of each of the responses occurred more rapidly during REM sleep than during non-REM sleep. It is concluded that habituation of the infant arousal sequence occurs with repeated tactile stimulation. There is a serial habituation of responses from the cortical to the spinal level, which occurs more rapidly during REM sleep. Rapid habituation to innocuous stimuli is probably beneficial in avoiding detrimental sleep disruptions. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 15 of 16 in PsycINFO 1999-2000/12

McSweeney, F. K., & Swindell, S. (1999). General-process theories of motivation revisited: The role of habituation. Psychological Bulletin, 125(4), 437-457.

The authors propose that the goal objects of motivated behaviors serve as reinforcers. Animals sensitize and then habituate to these reinforcers with repeated contact, altering their ability to control behavior. Several characteristics of motivation are consistent with this idea. Motivated behaviors decrease in strength with contact with the goal (habituation) and increase in strength in the absence of the goal (spontaneous recovery). They may increase in strength with initial contact with the goal (sensitization precedes habituation), with the presentation of irrelevant stimuli (sensitization), with changes in the goal (stimulus specificity), and with the presentation of dishabituators (dishabituation). The present idea is not a complete description of motivation. Habituation is only one among many contributors to its control. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 14 of 16 in PsycINFO 1999-2000/12

Miquel, M., Fuentes, I., Garcia Merita, M., & Rojo, L. (1999). Habituation and sensitization processes in depressive disorders. Psychopathology, 32(1), 35-42.

The aim of the present study was to investigate further into habituation and sensitization processes in depressive disorders. The depressive subjects were 27 outpatients. All of them were diagnosed according to Mental Disorders-III-Revised (DSM-III-R) criteria. Controls were 27 normal subjects. The amplitudes of electrodermal responses and the basal levels were recorded during a stimuli series of 15 80-dB tones and of 1,100-dB tone in the 11th trial. The depressive patients displayed lower basal conductance levels and lower conductance amplitudes in orienting responses to the first stimulus and to stimulus change. No differences were found in conductance response amplitudes of stimuli series, although a tendency towards smaller conductance amplitudes in depressive patients was observed before stimulus change. A trend towards habituation was detected in both groups, but no differences between them were present, and neither was the habituation velocity of depressives found to be unlike normals. Our results display lower responsivity in depressive patients, which reflects alterations in the sensitization process. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 12 of 16 in PsycINFO 1999-2000/12

Ramus, F., Hauser, M. D., Miller, C., Morris, D., & Mehler, J. (2000). Language discrimination by human newborns and by cotton-top tamarin monkeys. Science, 288(5464), 349-351.

Examines and compares speech perception among humans and nonhuman animals. Parallel experiments were conducted on human newborns and cotton-top tamarin monkeys to assess their ability to discriminate unfamiliar languages. A habituation-dishabituation procedure was used to show that human newborns and tamarins can discriminate sentences from Dutch and Japanese, but not if the sentences are played backward. Moreover, the cues for discrimination are not present in backward speech. This suggests that the human newborns' tuning to certain properties of speech relies on general processes of the primate auditory system. (PsycINFO Database Record (c) 2000 APA, all rights reserved)


Rankin, C. H. (2000). Context conditioning in habituation in the nematode Caenorhabditis elegans. Behavioral Neuroscience, 114(3), 496-505.

Habituation has traditionally been considered a nonassociative form of learning. However, recent research suggests that retention of this nonassociative form of learning may be aided by associations formed during training. An example of this is context conditioning, in which animals that are trained and tested in the presence of a contextual cue show greater retention than animals trained and tested in different environments. This article reports context conditioning in habituation in the nematode Caenorhabditis elegans. The results showed that retention of habituation to tap at both 10- and 60-s interstimulus intervals was significantly greater if training and testing occurred in the presence of the same chemosensory cue (NaCH-sub-3COO). This context conditioning showed both extinction and latent inhibition, demonstrating that these simple worms with only 302 neurons are capable of associative context conditioning. (PsycINFO Database Record (c) 2000 APA, all rights reserved)(journal abstract) Record 2 of 16 in PsycINFO 1999-2000/12

Rowland, W. J. (2000). Habituation and development of response specificity to a sign stimulus: Male preference for female courtship posture in stickleback. Animal Behaviour, 60(1), 63-68.

Examined biased patterns of habituation when reproductive male 3-spined sticklebacks, Gasterosteus aculeatus, responded to 1 of 2 dummy females (DF; both of whom were stationary and unreactive and so could not provide feedback to the males) displaying either a head-up, sexually receptive (SR) or horizontal-neutral (HN) posture. Males initially courted both about equally, but within 5 min, began to habituate and eventually attack (a behavior which increased 4-fold during the 1-hr trial) the HN DF. Courtship to the SR DF continued unabated throughout the trial and by 5 min exceeded courtship to the HN DF. Attack to the SR DF increased slightly in the 1st half of the trial then leveled off to about 1/3 that directed to the HN DF. It is speculated that the males' self-arousal to the HN posture reinforces their response. This sign's salience may develop through a process wherein the male recognizes and courts the SR posture and obtains self-arousal which counters habituation and helps maintain the response. The stimulus-response specificity of male courtship is assumed to have an innate basis but requires experience for full differentiation. The results also illustrate that rate or extent of habituation to different stimuli can differ within the individual and adaptively. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 11 of 16 in PsycINFO 1999-2000/12

Wilson, D. A. (2000). Odor specificity of habituation in the rat anterior piriform cortex. Journal of Neurophysiology, 83(1), 139-145.

Exposure to odorants results in a rapid (<10 sec) reduction in odor-evoked activity in the rat anterior piriform cortex despite relatively maintained afferent input from olfactory bulb mitral cells. To further understand this form of cortical plasticity, a detailed analysis of its odor specificity was performed. Habituation of odor responses in anterior piriform cortex single units was examined in anesthetized, freely breathing male rats. The magnitude of single-unit responses of layer II/III neurons to 2-sec odor pulses were examined before and after a 50-sec habituating stimulus of either the same or different odor. The results showed that odor habituation was odor specific, with no significant cross-habituation between either markedly different single odors or between odors within a series of straight chain alkanes. Furthermore, habituation to binary 1:1 mixtures produced minimal cross-habituation to the components of that mixture. These latter results may suggest synthetic odor processing in the olfactory system, with novel odor mixtures processed as unique stimuli. Potential mechanisms of odor habituation in the piriform cortex must be able to account for the high degree of specificity of this effect. (PsycINFO Database Record (c) 2000 APA, all rights reserved) Record 6 of 16 in PsycINFO 1999-2000/12

Zuberbuehler, K., Cheney, D. L., & Seyfarth, R. M. (1999). Conceptual semantics in a nonhuman primate. Journal of Comparative Psychology, 113(1), 33-42.

Some animal vocalizations have been described as referential, or semantic, because individuals respond to them as if they designate some object or event. Alternatively, subjects may simply attend to the acoustic features of calls rather than their meanings. Field playback experiments on diana monkeys (Cercopithecus diana diana) tested these hypotheses using the calls of leopards and eagles and the males' alarm calls to these predators. In the experiment, 2 calls were played in sequence, separated by 5 min of silence, such that they were either (a) similar in acoustic and semantic features, (b) similar in semantic features only, or (c) different in both acoustic and semantic features. Subjects readily transferred habituation across acoustic but not semantic features, suggesting that they attended to the calls' underlying meanings. (PsycINFO Database Record (c) 2000 APA, all rights reserved)(journal abstract)