Age-related changes in processing auditory stimuli during visual attention: Evidence for deficits in inhibitory control and sensory memory.

Age-related declines in attention and cognition have been associated with a difficulty in inhibiting the processing of task-irrelevant information (i.e., the inhibitory deficit hypothesis). However, evidence supporting the inhibitory deficit hypothesis remains equivocal, in part because of complexities in examining the processing of irrelevant stimuli using purely behavioral techniques. The effects of age on the processing of task-irrelevant stimuli were examined using scalp-recorded event-related brain potentials. Participants performed a visual discrimination task while standard and deviant auditory stimuli were presented in the background. Deviant auditory stimuli generated a mismatch negativity (MMN) wave that decreased with age, in part because of an age-related enhancement in sensory-evoked responses. The age-related changes in processing task-irrelevant auditory stimuli are consistent with the inhibitory deficit hypothesis and suggest that impaired inhibitory control of sensory input may play a role in the age-related declines in performance during selective attention tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of brief sensory deprivation on field dependence.

To determine whether brief sensory deprivation would act to decrease perceptual field dependence, 41 male and female college students were given the Rod and Frame Test (RFT). ? of the group then underwent 1 hr. of sensory deprivation, after which a 2nd RFT indicated a significant decrease (p     

Effect of auditory deprivation on visual resolving power.

Conducted 2 experiments in which changes in the critical flicker fusion (CFF) were determined during and after auditory deprivation (silence). In Exp I, 36 male undergraduates were exposed to 1 wk of auditory deprivation, measurements of the CFF being taken at daily intervals and at Days 1, 2, 3, and 7 after the termination of the experimental condition. Results show that the experimental group exhibited a significant progressive improvement in visual resolving power as a function of auditory deprivation and, following its termination, a gradual decline towards the pre-experimental baseline. On the other hand, 2 control conditions, a group of confined Ss, and a non-confined group showed no systematic changes in the CFF. In Exp II with 6 new Ss, the period of auditory deprivation was extended to 14 days. Results again reveal a progressive improvement on the CFF during the 1st wk of silence followed by an asymptotic performance during the 2nd wk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Birth order of volunteers for sensory deprivation.

Published data have indicated the preponderance of 1st-born individuals among volunteer Ss in experiments involving group interaction and cooperation. The results were explained on the basis of strong affiliative tendencies among 1st borns. This report shows a similarly high proportion of 1st borns among individuals volunteering for a sensory deprivation study which called for total isolation of the S, and suggests that an explanation based only on affiliation motives may not be adequate for an understanding of the overrepresentation of 1st borns among volunteer Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

First came the trees, then the forest: Developmental changes during childhood in the processing of visual local-global patterns according to the meaningfulness of the stimuli.

This study investigated how global and local perceptual processes evolve during childhood according to the meaningfulness of the stimuli. Children had to decide whether visually presented pairs of items were identical or not. Items consisted of global forms made up of local forms. Both global and local forms could represent either objects or nonobjects. In dissimilar pairs, items differed at one level (target level), while the other level included similar forms on both sides (irrelevant level). The results indicate an evolution from local preference at 4 years of age to adult-like global preference at 9 years of age. Moreover, as previously reported in adults, regardless of age, identification impaired performance when the irrelevant level was made of objects and the target level was made of nonobjects (interference). However, in younger children, this interference existed even when objects were present at all levels, suggesting that the strategy used to perform the comparison task also varied according to age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Learning about deprivation intensity stimuli.

Rats demonstrated that they can use deprivation-produced stimuli as discriminative signals for shock in three experiments that used observation of freezing behavior as the index of learning. In Experiment 1, one group was shocked under 24-hr, but not under 0-hr food deprivation. Another group received the reversed discrimination. Both groups froze more under their shocked than under their nonshocked deprivation level. Furthermore, freezing was greatest under a given deprivation level for the group shocked under that level. Behavior was shown to be a function of this learning during subsequent testing under other deprivation levels. In Experiment 2, rats discriminated between deprivation intensities approximating those encountered under free-feeding conditions, and behavior under other deprivation levels also depended on this learning. Experiment 3, using 6- and 23-hr food deprivation, showed that discriminative responding occurred in the absence of cues arising from the recent memory of food in the home cage. Generalization of discriminative control to cues produced by intubation of a high calorie load and to injection of insulin (Experiment 3{a}) provided evidence that animals learned about the interoceptive stimulus consequences of their deprivation states. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temporal changes in cutaneous sensitivity during prolonged visual deprivation.

Conducted 2 experiments with a total of 62 male undergraduates and 60 controls in which various measures of cutaneous sensitivity were administered at intervals of 0, 1/2, 1, 2, 3, 5, and 7 days of visual deprivation (darkness). Relative to controls results reveal no significant differences in performance on the 2-point threshold and on measures of pressure and pain sensitivity, although on the last 2 measures a definite trend toward an improvement was observed after the 3rd day. However, results on the tactual fusion threshold reveal a linear improvement in performance as a function of increasing duration of visual deprivation, a facilitatory effect which was already present, to a statistically significant degree, at the 1st test period of 12 hr. Results of a 3rd experiment, also with 32 experimental ss and 30 controls, indicate that this improvement on the tactual fusion task 1st appeared somewhere between 4 and 12 hr. Of deprivation. Various hypotheses are offered to account for these differential results and findings are related to D. P. Schultz's sensoristatic theory. (french summary) (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A note concerning sensory deprivation.

Argues that in the short span of a few years the topic of sensory deprivation has become fashionable in psychological society. It has generated considerable experimental research, has proven itself worthy of foundation support, and has been a popular theme at APA and regional meetings. An excerpt from Melville's "Moby Dick" is presented to provide a literary precedence for this topic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lesions of the amygdala central nucleus abolish lipoprivic-enhanced responding during oil-predicting conditioned stimuli.

T. L. Davidson, A. M. Altizer, S. C. Benoit, E. K. Walls, and T. L. Powley (see record 1997-43076-013) reported that rats show facilitated responding to conditioned stimuli (CSs) that predict oil, after administration of the lipoprivic agent, Na-2-mercaptoacetate (MA). This facilitation was blocked by vagal deafferentation. The present article extends that investigation to another structure, the amygdala central nucleus (CN). The CN receives inputs from dorsal vagal nuclei, and neurotoxic lesions of this nucleus are reported to abolish feeding in response to lipoprivic challenges. In Experiment 1, rats with ibotenic acid (IBO) lesions of the CN failed to show enhanced appetitive responding during oil-predicting CSs after administration of MA. Experiment 2 used a conditioned taste-aversion procedure to establish that rats with IBO lesions of the CN were able to discriminate the tastes of sucrose and peanut oil and had intact CS–US representations. It is concluded that the amygdala CN is a necessary structure for the detection of lipoprivic challenges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sensory deprivation versus sensory variation.

Compared verbal and physiological reactions to sensory deprivation (SD) and extreme sensory variation (SV). 22 male undergraduates were confined to a cubicle for 8 hr. in each condition on 2 different occasions. 2 other 8-hr sessions were spent in a relatively normal, nonconfined condition. Ss found SD more boring, dislikable, and anxiety and depression provoking than SV. More unreality stress was reported after SD. However, more autonomic activation was found in SV. Both SD and SV produced more hostility, somatic complaints, and adrenocortical output than control conditions. Trait anxiety was associated with stress response to both conditions. Subjective stress is associated with a condition, SD, which produces less than optimal arousal. Confinement may produce hostility and adrenocortical activation at either extreme of sensory variation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of visual deprivation on depth discrimination of hooded rats.

In a study with hooded rats (N = 530), Ss raised in the dark were compared to light-reared controls. 21-day-old dark-reared (DR) Ss were not different from controls in the discrimination of 4-in depths, but 30-day-old DR Ss were deficient. 60-day-old DR Ss were deficient in discriminating 4-, 6-, and 8-in depths. 30-day-old DR Ss recovered the loss in depth discrimination after 48 hrs in the light. 60-day-old DR Ss had no noticeable recovery to the 4-in depth discrimination, but they did recover discrimination of the 6-in depth after 72 hrs in the light. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and distraction by highly familiar stimuli during visual search.

P. Rabbitt's (1965, 1968) theory regarding age-related changes in cognition proposes that aging is accompanied by a decreased ability to ignore irrelevant information (perceptual noise). The present experiment examined age differences in the extent to which highly familiar stimuli used as perceptual noise could disrupt visual search performance. On Days 1–4, 10 Ss aged 19–27 yrs and 10 Ss aged 63–77 yrs performed a search task with specific, unchanging sets of target and nontarget stimuli (letters). Performance on a subsequent search task (Day 5) was disrupted when these familiar stimuli appeared as noise items in the displays, as compared with trials on which only new, unpracticed stimuli were used. The magnitude of the distraction associated with the familiar stimuli on Day 5 was equivalent for the 2 age groups. However, age differences in Day 5 search performance increased as more items in the simulus display required inspection. Age differences were thus influenced more by the requirement to attend to relevant information than by distraction from irrelevant information. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and visual marking: Selective deficits for moving stimuli.

The selective processing of new visual information can be facilitated by the top-down inhibition of old stimuli already in the visual field, a capacity-limited process termed visual marking (D. G. Watson & G. W. Humphreys, 1997). Three experiments assessed the effects of aging on visual marking using stationary (Experiment 1) and moving (Experiments 2 and 3) items. For young participants, visual marking was observed in all experiments. For older participants, visual marking was observed only with stationary items. The results are not consistent with any simple account of general age-related decrements and provide further support for the deployment of different methods of visual marking depending on the properties of the old items and the current task demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of pre-adapting spectral stimuli on visual responses

Electroretinograms (ERGs) were recorded following pre-adapting exposures to radiometrically and photometrically matched spectral stimuli. The magnitudes of three aspects of the ERG varied as a function of the pre-adapting wavelength. Longer wavelenght pre-adapting stimuli produced less suppression of the response magnitudes than stimuli from the short wavelenght end of the spectrum. The implications of the findings for display design and cockpit-light-source design and management are discussed.     

Regional cerebral blood flow increases during preparation for and processing of sensory stimuli

The transferrin receptor (TFR) has been detected in tissues characterised by a high degree of proliferation. We have developed a procedure for isolating TFR from human placental tissues by affinity chromatography on transferrin-Sepharose. Using gel filtration and electrophoresis in 7% PAAG, it has been shown that the molecular mass of the protein is 180 kDa. The protein has a subunit structure and is made up of two identical subunits, 90 kDa each. The constant for the protein binding to transferrin is equal to 5 x 10(-9) M. The yield of the protein isolated by the novel procedure exceeds 5-fold that obtained by previously described methods.     

The location of noisy visual stimuli.

Examined the results of experiments where Ss were required to detect the misalignment of 2 abutting dot clusters on a monitor screen. Thresholds varied with the square root of dot density and did not appear to be affected by changing the sampling strategy used to generate the random dot clusters. Comparison of the Ss' performance with that expected of 3 information processing strategies suggested that Ss accomplished the task by locating the edges of the dot clusters rather than by extracting measures of global scope or of central position. The efficiency with which edge information was extracted was approximately 50% for low-density stimuli and declined exponentially with increasing dot density. (French abstract) (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparison of the effects of prolonged sensory deprivation and perceptual deprivation.

Compared the effects on 161 male undergraduates of sensory deprivation (sd) and perceptual deprivation (pd), each of 4-days duration. Ss were tested on measures of eeg activity, subjective stress, and on 22 different psychological and somatic symptom areas derived from myers' postisolation questionnaire. Results reveal that both sd and pd produced a decrease in occipital alpha frequency, an increased degree of subjective stress, and a higher incidence of 16 of the 22 questionnaire-elicited symptoms. Virtually no significant differences were observed between the 2 experimental conditions, a finding contrary to 2 current deprivation theories which would predict that pd should produce a greater impairment than sd. It is suggested that these negative results may be related to the shortness of the deprivation period. (french summary) (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of visual deprivation on development of depth perception in the rat.

Compared the behavior of light- and dark-reared Long-Evans hooded rats (N = 1,786) at 20-160 days of age in 3 experiments using a visual cliff apparatus in which the depth of the deep side could be varied. Differential depth thresholds obtained revealed no significant difference at 20 days in perceptual ability due to rearing condition. Both groups showed improvement in depth perception over the next 40-60 days. Dark-reared Ss did not improve at the same rate nor acquire the same degree of discriminative ability as did light-reared Ss. The performance of light-reared Ss leveled off after 100 days, but dark-reared Ss' ability deteriorated. Results are discussed in terms of further specification of the effects of visual deprivation on perceptual capacities. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Feedback stimuli and the extinction of avoidance responding in rats.

Trained 24 female Wistar rats to avoid electric shock in a 2-way shuttlebox with a feedback stimulus contingent upon each avoidance response in order to investigate extinction of the avoidance response. Shock presentations were then discontinued. Results indicate that the temporal relationship of the avoidance response and feedback was disrupted by continuously presenting the feedback stimulus or by random presentations of the stimulus. These procedures prolonged extinction relative to complete withdrawal of the feedback, but enhanced extinction relative to response contingent presentations of the feedback. Parallels between patterns of extinction found with these procedures and those found with appetitive reinforcers are discussed. (French abstract) (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Potency of food deprivation intensity cues as discriminative stimuli.

Rats were trained to use stimuli arising from 0 and 24 hrs without food as discriminative signals for shock. In Exp 1, one group was shocked under 0-hr food deprivation and not shocked under 24-hr food deprivation. Another group received the reverse contingency. The groups received only 3 training trials under each deprivation level. Learning was revealed in a test phase when greater extinction of freezing was observed under the nonshocked than under the shocked deprivation level for both groups. A similar pattern of results was obtained in Exp 2 when auditory cues were also relevant throughout training. Furthermore, prior training with food deprivation cues seemed to reduce learning about auditory cues subsequently trained in compound with deprivation stimuli. The results indicate that food deprivation intensity cues can be potent discriminative stimuli. The idea that deprivation cues function as conditioned modulatory stimuli cues is also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)