Recognition memory, sleep and circadian rhythms.

Examined the effects of sleep on memory. In Exp 1, 43 Ss learned a list of words and were tested for recognition 24 hrs later. For the delayed sleep group, learning was followed by a period of wakefulness; for the immediate sleep group, it was followed by a period of sleep. Retention was significantly better for the immediate sleep group. In Exp 2, 69 Ss were tested approximately 8 hrs after learning. The normal waking group learned and was tested after a period of daytime wakefulness; the normal sleep group learned and was tested after a period of nighttime sleep; and the sleep deprivation group learned and was tested after a period of nighttime wakefulness. In agreement with previous work (e.g., J. G. Jenkins and K. M. Dallenbach, 1924), retention for the normal sleep group was superior to that of the normal waking group; however, retention was not better for the normal sleep group than for the sleep deprivation group. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Some effects of sleep deprivation on tracking performance in static and dynamic environments.

The influence of 34 and 55 hrs of sleep deprivation on scores derived from manually tracking the localizer needle on an aircraft instrument was assessed in 2 experiments under both static (no motion) and dynamic (whole-body angular acceleration) laboratory conditions. In each study, 20 21–30 yr old men, equally divided into control and sleep-deprived groups, were tested in an enclosed rotator, in darkness with the exception of the illuminated tracking display. Significant decrements in dynamic performance were uniformly obtained after 24 hrs and more of sleep loss. Static scores were less consistently impaired. Administration of d-amphetamine after 55 hrs of sleep loss reduced error for both static and dynamic tracking; although performance at both tasks remained poorer for sleep-deprived Ss, their static tracking scores did not differ significantly from controls 2 hrs after drug ingestion. Results indicate clear performance impairment for an aviation-related task after 1 night without sleep. Impairment is generally greater with increasing amounts of sleep loss and is more pervasive in motion environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual stimulation: Effects on vestibular habituation.

Studied the influence of various forms of visual stimulation presented during the course of vestibular habituation to a caloric stimulus, using 32 adult cats. Eye movements which were either complimentary or in opposition to the induced vestibular nystagmus were produced with an optokinetic drum. In addition, the effect of visual fixation during vestibular-response periods was studied. In all cases, Ss that received visual stimulation during the majority of the caloric trials habituated more slowly than did Ss that received all the habituation trials in total darkness. Data conflict with previous reports of vestibular-visual interactions. Possible explanations for the discrepancy include species differences, distraction provided by the visual stimuli, and the transfer of learning from the dark to light conditions. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Short-term retention of habituation in the rat: A developmental study from infancy to old age.

Allowed 168 infant, weanling, adult, and elderly Blue Spruce hooded and albino rats to habituate to a simple exploratory situation and then tested them for retention after 1 min, 1 hr, or 24 hrs. Infants habituated more slowly than older Ss as indicated by time to habituate and response frequency measures. No age differences were found after a 1-min retention interval, which suggests that the final levels of original habituation did not differ. However, after longer intervals (1 hr and 24 hrs), infants showed poorer retention of habituation than the older Ss. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vestibular habituation in paralyzed cats.

Studied the role of the eye movement response in the production of vestibular habituation in 12 cats. One group of Ss was subjected to an habituation series of 15 unilateral caloric irrigations while paralyzed with gallamine triethiodide. A 2nd group underwent an identical habituation procedure but was not paralyzed. Tests conducted following recovery from paralysis showed that the responses of the previously is Ss were habituated and did not differ from the responses of Ss habituated in a normal manner. Data support a central origin for the phenomenon of vestibular habituation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neonatal habituation and dishabituation to tactile stimulation during sleep.

Two experiments examined habituation and dishabituation of behavioral responding to repeated presentations of a tactile stimulus (brush stroke) in 48 newborns during the 1st epoch of active-quiet sleep following a feeding. Exp I demonstrated habituation to a repeatedly presented brush stroke to the ear but failed to demonstrate dishabituation (i.e., response recovery) to the original brush stroke following an intense auditory stimulus (86 dB rattle sound). A post hoc control group showed that the intense auditory stimulus had suppressed subsequent responding to the tactile stimulus. Exp II replicated the habituation phase of Exp I and demonstrated response recovery to stimulation at a novel tactile site and to an auditory probe. Results indicate that the habituation paradigm used in infancy research could be successfully extended to the tactile modality. It is also suggested that prior auditory stimulation, but not prior tactile stimulation, might direct attention away from a subsequently presented tactile stimulus. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Habituation of the EEG arousal response in rats: Short- and long-term effects, frequency specificity, and wake–sleep transfer.

In 3 experiments with 78 male Holtzman albino rats, presentation of auditory stimuli over interstimulus intervals (ISIs) of several minutes to sleeping Ss produced significant habituation of the EEG arousal response. The arousal response habituated to an asymptote after only 2 or 3 stimulus presentations. Little or no spontaneous recovery occurred between sessions separated by 24 or 72 hrs. The habituation produced by a single stimulus presentation was retained for at least 24 hrs, and orderly habituation was shown with a 24-hr ISI. Approximately 90% retention of habituation was shown 32 days following 10 stimulus presentations, and some degree of retention was shown for as long as 50 days. After habituation had reached a long-term asymptote, 600 stimulus presentations over 2-sec ISIs produced further response decrements, but these decrements recovered completely within a matter of minutes and responsiveness returned to the previously established long-term asymptote. Habituation was shown to be frequency-specific over both 24-hr and 32-day intervals. Habituation produced by stimulus presentations to awake Ss transferred to the condition in which stimuli were presented to sleeping Ss. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance deficits following short-term partial sleep deprivation and subsequent recovery oversleeping.

Tested the effects on performance of 1 and 5 cumulative nights of partial sleep deprivation (PSD; less than 40% per night) and 1 and 2 nights of subsequent recovery oversleep (+40%, +20% respectively), compared to pre- and postbaselines in 7 undergraduates (18–23 yrs). Assessment measures included the standard 1-hr Wilkinson auditory vigilance test, 2 RT tests, the Stanford Sleepiness Scale, and Ss' self-ratings. The experiment lasted 8 days, and Ss were tested twice each day for 2 hrs. Results show deficits in performance on the vigilance and RT tests, as well as lower self-ratings of alertness and energy and other transient deficits after 5 nights PSD. Time of day effects were most pronounced on the initial days following sleep reduction or gain. Results indicate that a typical work week of undersleeping on weekdays and oversleeping on weekends may produce performance deficits. This may be due to a sudden shift in the phase of sleep, rather than sleep loss per se. (French abstract) (48 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

REM motivation induced by brief REM deprivation: The influence of cognition, gender, and personality.

Prominence of the brain's right-hemisphere information processing and intensity of dream experience have been proposed as important psychological aspects of REM sleep. Either view is consistent with the prediction that the effect of REM deprivation will depend in part on the nature of cognitive activity that is initiated at the onset of each REM period and that "substitutes" for the interrupted REM process. In the present study with 84 female and 73 male undergraduates, the effect of REM deprivation was more striking for females given a digits task than for females given a fantasy-reporting task during awakenings used to induce REM deprivation for the 1st 6 hrs of the night. High neuroticism (Maudsley Personality Inventory) appeared to exaggerate the effect. No corresponding pattern was observed for males. These preliminary findings are in part consistent with the view that the "motive" for REM sleep and dreaming may be exaggerated by cognitive activity that is functionally incongruent with those processes. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term retention of habituation in the sea anemone (Anthopleura elegantissima).

Long-term retention of habituation was assessed over a 4-day period in the contraction response of intertidal sea anemones. Substantially less responding was evident as much as 72 hrs after initial training either with or without interpolated training on Day 2. Retained response decrements were indicated both by an absence of spontaneous recovery and by the potentiation of habituation. Although slight differences in habituation rates were evident between the 2 components of contradiction (closure and reexpansion), no differences appeared in the amount of long-term retention observed in each. Results are discussed with respect to the possible nature of retention processes occurring in the coelenterate nerve net. It is concluded that the generalized association of persistence with increased complexity is invalid. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maternal deprivation potentiates pituitary-adrenal stress responses in infant rats.

Examined the effect of maternal deprivation on the pituitary-adrenal response of 12-, 16-, and 20-day-old rat pups to novelty stress. Infants were either deprived individually in heated incubators or left in the home nest with their mother and then tested for corticosteroid response to 30-min exposure to a novel test arena. In Exp 1, the magnitude of the stress response (SR) was a positively accelerated function of the deprivation interval. SRs were not increased after 1 hr of deprivation, were modestly increased after 8 hrs of deprivation, and were dramatically increased after 24 hrs of deprivation. Exp 2 investigated whether potentiation of the SR resulted from the maternal or the nutritive components of the deprivation procedure. Pups were tested under 1 of 4 treatment conditions formed by a 2 (Maternally Deprived vs Nondeprived)?×?2 (Nutritively Deprived vs Nondeprived) factorial design. At 12 and 16 days of age, potentiation of the SR was traced to the absence of maternal care and not nutrients. At 20 days of age, both maternal and nutritive deprivation contributed to the potentiated SR. Exp 3 showed that this effect was mediated by increased adrenocortical sensitivity to ACTH, because the corticosteroid response to exogenous ACTH administration was also increased by maternal deprivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Habituation of startle response, lick suppression, and exploratory behavior in rats with hippocampal lesions.

34 male albino Holtzman rats with bilateral hippocampal lesions (HLs) and 22 controls with neocortical lesions (NLs) were compared on the habituation of lick suppression and startle response. Ss with HLs showed no consistent differences from controls on any measure within these 2 response systems. Ss with HLs showed significant retention of habituation over periods of 24 hrs and 21 days. Experimental and control differences were not revealed when stimulation was presented on a 1-sec interstimulus interval. None of these results varied with the extent of the HLs, which ranged from relatively small lesions restricted to the dorsal hippocampus to large lesions that damaged the hippocampus in its dorsal, posterior, and ventral aspects. In contrast to the startle response and lick suppression results, HLs significantly disrupted Y-maze exploratory behavior, and the disruption was directly related to the extent of hippocampal damage. Data suggest that the hippocampus is not involved in any important way in the control of either short- or long-term habituation of elicited, reflex-like behaviors but is importantly involved in the control of emitted, exploratory behaviors. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The characterization of neonatal behavior: A dimensional analysis.

137 healthy human neonates were tested in 2 procedurally identical 3-hr sessions at 2 days of age. Each session contained 21/2 hrs of nonintervention during which sleep and other spontaneous behaviors were assessed and 1/2 hr of stimulation during which various responses were elicited. Obtained were measures describing characteristics of active sleep, quiet sleep, sucking, and crying. These measures along with measures of body size and gestational age were factor analyzed, yielding 3 factors that were stable across both sessions. The factors were labeled Reactivity-Irritability, Maturity, and Reflexive and Discriminative Sucking. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

REM drive and function: A study of the interactive effects of personality and presleep condition.

To investigate individual differences in REM sleep drive and function, a factorial design that manipulated type of experimental presleep stimulation (insolvable, solvable, or no problems), personality (repressor or sensitizer), and sleep manipulation (REM deprivation or nondeprivation) was used. Data were obtained from 169 18–28 yr old male undergraduates who completed the Neuroticism scale of the Maudsley Personality Inventory as a measure of repression–sensitization. REM drive was assessed in terms of initial REM sleep onset and inter-REM interval throughout the night; REM function was assessed in terms of postsleep mood (Multiple Affect Adjective Check List) and anagram performance. Results reveal REM drive to be an interactive function of personality and presleep stimulation, but there was little evidence of an adaptive function for REM sleep. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Habituation and retention of habituation of responses to air puff of normal and decerebrate earthworms.

Exp I showed habituation and retention of habituation for 24 and 48 hrs for movement responses of 23 earthworms, (Lumbricus terrestris) when an air puff was used as the stimulus. Habituation was shown by reductions in frequencies and magnitudes of backward movements. Exp II with 38 Ss showed that ablation of the suprapharyngeal ganglion did not affect habituation or retention. For all groups (ablated, normal, and sham operated), a 10-sec intertrial interval (ITI) led to faster habituation and rehabilitation (the test for retention) than a 60-sec ITI. Data extend findings of habituation and retention for earthworms and suggest that cerebral ganglia do not mediate responses to air puff. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Motivational and neuroanatomical specificity of hypodipsia for aversive solutions produced by medial preoptic injury to the rat.

In an experiment with a total of 28 Sprague-Dawley rats, bilateral medial preoptic lesions dramatically lowered the rejection threshold for quinine-adulterated water but not for food in 24-hr forced-choice tests. The detection threshold for quinine in a 2-bottle choice test, however, was unaffected by the medial preoptic lesion. Bilateral septal and lateral preoptic lesions had no effect on any quinine adulteration tests. The enhanced rejection of quinine-adulterated water in a forced-choice test by medial-preoptic-damaged Ss was also observed after 24 hrs of water deprivation. The plasma osmolality of medial preoptic Ss was significantly elevated above controls after 24 hrs of water deprivation. Findings suggest that a medial preoptic lesion produces a deficit in thirst-motivated behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Control of ingestion by oral habituation in rat pups.

The role of habituation of mouthing activity in the control of ingestion was investigated in 6-, 12-, and 18-day-old rat pups. In pups at all ages, oral habituation to a flavored diet inhibited ingestion of a continuous oral infusion of that same diet. 12-day-old pups that had orally habituated to a diet continued to consume less of a continuous oral infusion of that diet both 30 min and 3 hrs later, and the duration of suppressed ingestion was shown to be dependent on the rate of stimulus presentation during habituation experience. These data suggest that oral habituation may be a diet-specific influence on both intra- and intermeal patterning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of overtraining and high activation on bar pressing of rats tested under water deprivation.

Trained 2 groups of 9 male albino Sprague-Dawley rats each in a Skinner box under 24 hrs of water deprivation; Group 1 received 15 daily training sessions, Group 2 30 sessions. In Exp II, 4 groups (9 Ss each) were also trained in a Skinner box but under different conditions of water deprivation (24, 36, 48, and 60 hrs, respectively). In both experiments, the relationship between performance and activation was evaluated by submitting each group to successive and independent conditions of water deprivation (24, 36, 48, 60, and 72 hrs). Heart rate was used as an index of activation during training and during the test phase. Overtraining (Exp I) and high activation during training (Exp II) prevented the drop in performance usually observed under high levels of activation. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhancement of feeding produced by stimulation of the ventromedial hypothalamus.

Following 24 hrs of food deprivation, 39 male hooded Long-Evans rats were subjected to low-level electrical stimulation in the ventromedial hypothalamus. Stimulation produced a 20% increase in the mean amount of food eaten during a 100-sec interval. This effect was eliminated when Ss were allowed to ingest more than 1 g of food immediately prior to testing. The increase in rate of feeding was most reliable with electrode placements in, or touching the edge of, the ventromedial nucleus (VMN). Suppression of feeding was observed during stimulation through the same electrodes at higher current levels, but the lowest thresholds for suppression were associated with placements dorsal and lateral to the VMN. Data support the suggestion that the ventromedial hypothalamus contains a neural mechanism which facilitates feeding. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

One night of total sleep deprivation impairs implicit learning in the serial reaction task, but not the behavioral expression of knowledge.

Implicit sequence learning in the serial reaction task suffers from total sleep deprivation. The authors compared implicit-learning scores in a sleep-deprivation (SD) group (n = 12) and a control group (n = 6). Both groups were tested immediately after learning a 1st sequence; a delayed test was conducted on the next day (after a night without sleep in the SD group). Immediately after the delayed test a 2nd sequence was learned, followed by an immediate test and a delayed test toward the end of the experiment. In the SD group implicit-learning scores were reduced in both tests of the 2nd sequence, but in neither test of the 1st sequence. Thus, 1 night of total sleep deprivation impairs the acquisition of implicit sequence knowledge, but not its behavioral expression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)