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The present study examined auditory backward masking in a task requiring subjects to label a target sound as having a long or short duration. Perception of target duration was influenced by the interaction of the effects of (1) the similarity of the target/mask duration, (2) the acoustic similarity of the target and mask (tone vs. white noise), and (3) the interstimulus interval (ISI) between the target and mask. Specifically, relative to the long duration (100 ms) mask, the short duration (40 ms) mask helped performance for the target having a similar short duration (55 ms) but hurt performance for the target having a dissimilar long duration (85 ms). This effect of the similarity of target/mask duration was greater for acoustically similar targets and masks than for acoustically dissimilar targets and masks, and particularly so at the intermediate (45, 105, 165, 205 ms) ISIs. These results can be explained within the framework of Massaro and Idson's (1976) two-stage model by assuming that masking of perceived auditory duration is the result of two processes: (a) the mask's interruption of target processing in a peripheral auditory processing stage, and (b) a confusion of which item is the target vs. the mask, due to temporal uncertainty in the transfer of the target and mask into a central auditory processing stage.

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Mental status testing is an essential element of evaluating elderly patients. A structured examination often helps identify the etiology of symptoms that are responsible for changes in patient behavior, that lead to family stress, but that are otherwise not indicative of cognitive dysfunction. A structured mental status examination is also helpful in distinguishing cognitive changes caused by dementia, delirium, and depression. This article examines the steps in mental status assessment and the commonly used assessment instruments. The experience of a family medicine ambulatory multidisciplinary evaluation service in mental status testing is discussed.

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A number of explanations for the modality effect in immediate serial recall have been proposed. The auditory advantage for recall of recency items has been explained in terms of (1) the contributions of precategorical acoustic storage (PAS), (2) an advantage of changing-state over static stimuli, and (3) an advantage of primary-linguistic coding. Four experiments were conducted to evaluate these hypotheses. In the first, subjects viewed seven consecutive rectangles of different colors on a computer monitor. A small recency effect was obtained when the task was to recall the colors of the rectangles in order, with the size of the effect being independent of whether the rectangles remained stationary on the screen or moved in one of four directions. However, when the task was to recall the direction of movement of the rectangles, a larger recency effect was found. This pattern of results was interpreted as suggesting that recency effects are enhanced by changing-state stimulus information, but only when the changing-state information serves to identify the stimulus. Experiments 2 and 3 provided converging evidence by demonstrating an analogous recency advantage for changing-state visual stimuli that were somewhat different from those of Experiment 1. Experiment 4 demonstrated recency effects with synthesized speech stimuli that were substantially greater than were those found with the changing-state visual stimuli of the first three experiments. Implications of the results for the PAS, changing-state, and primary-linguistic hypotheses, as well as temporal-distinctiveness theories of recency, are discussed.

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The role of similarity in memory for location of pictures was examined. Undergraduates memorized the locations of 10 pictures situated within a map. The similarity of the pictures was manipulated. Two days later, subjects were tested for their memory of the locations. The results indicated that subjects clustered the locations of the pictures on the basis of pictorial similarity, such that locations of similar pictures were judged as closer than equidistant locations of dissimilar pictures. The results are discussed in the framework of a hierarchical model of spatial memory.

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The aging eye undergoes a variety of structural and physiologic changes that can impair vision and cause functional disability. Among the changes are backward displacement of the eye into the orbit, thickening and yellowing of the lens, decrease in pupil size, increase in laxity of the lids, and accumulation of waste products in the retina. The specific diseases of the eye that occur with aging include macular degeneration, cataracts, glaucoma, diabetic retinopathy, and sudden vision loss. Preventive care both in old age and earlier in life may help forestall ocular changes and the subsequent morbidity and mortality they cause. Environmental changes to accommodate visual change can be important in accident prevention and in improved functioning and quality of life.

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The long-term efficacy of digoxin maintenance therapy must be determined individually for patients with normal sinus rhythm who have a history of congestive heart failure but no remaining signs or symptoms. Predictive factors for successful discontinuation of the agent in the elderly include normal mental status (including absence of depression), ability to adequately perform activities of daily living, general feelings of well-being, absence of multiple organic disease, absence of multiple drug use, and no evidence of existing congestive heart failure or atrial fibrillation. Our findings indicate that physicians and patients need to reexamine the concept that congestive heart failure is necessarily a chronic disease. Certainly, evidence exists that continuing digitalis therapy indefinitely is inappropriate and may be harmful. Further investigation may prove that congestive heart failure in the elderly, like pneumonia, is a common acute occurrence and in many cases not a chronic state for which patients are destined to receive medication indefinitely. We hope that the findings from our small sample will stimulate other investigators to question the indiscriminate long-term use of digitalis in the elderly.

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Five adult listeners who had extensive previous practice on a pitch discrimination task participated in an auditory backward recognition masking (ABRM) experiment. S identified the relative pitch "higher"-"lower" of a test tone. A standard tone of 20 msec duration at 800 c/s was followed after 500 msec by a similar 20-msec test tone at 800 +/- delta f. delta f varied from 3.3-11.4 c/s across Ss, adjusted for each S to yield approximately 75%-correct performance. The test tone was followed, after a silent interval of 20-250 msec, by a 100-msec mask, either a tone of 800 c/s or white noise. All stimuli were approximately equal to 77 dbA. All Ss exhibited substantial ABRM when the backward mask was a tone but substantially less when it was white noise. Evidently it is not necessary to use relatively naive listeners to demonstrate ABRM. The performance of most Ss was reduced by the tone masker (i.e., ABRM was in evidence) to chance or nearly chance levels (i.e., little or no ABRM) until the ISI exceeded 80 msec, and for 3 of the Ss ABRM with the tone masker was still evident after 250 msec. It was concluded that a backward mask interferes with test-tone information held in a multichannel preperceptual store and that such interference depends, in part, on the degree to which the properties of the test tone and mask overlap.

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A recent study in England indicated that people prone to orthostatic hypotension are at increased risk of developing accidental hypothermia. Thus, a history of orthostatic hypotension might be prudently viewed as a risk factor. Symptoms are insidious. Since the sensation of cold seems to disappear after the core temperature falls below 95 degrees F, the recognition of cold is transient at best, and often minimal, once the patient is in the hypothermia range.

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An experiment was conducted to evaluate the effect of blank time between picture presentations on retention of two types of picture information: specific detail information and general visual information. A series of slides of "everyday" scenes was presented, and the blank time between slide presentations was varied. After presentation of the series of slides, memory for specific details and general visual information was probed using a forced-choice testing procedure. Although previous research failed to find blank-time effects using similar stimuli, it was thought that by keeping both slide presentation times and blank times constant within each experimental block, an effect of blank time might be found. The results indicated that retention of both specific details and general visual information was aided by the extra rehearsal opportunity afforded by longer blank times; there was no interaction between the type of information probed and the duration of blank time. It is suggested that because the blank-time variable affected retention of specific detail and general visual information equally, the two types of information may be held by a common coding system.

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This article considers the use of auditory backward recognition masking (ABRM) and stimulus suffix experiments as indexes of preperceptual auditory storage. In the first part of the article, two ABRM experiments that failed to demonstrate a mask disinhibition effect found previously in stimulus suffix experiments are reported. The failure to demonstrate mask disinhibition is inconsistent with an explanation of ABRM in terms of lateral inhibition. In the second part of the article, evidence is presented to support the conclusion that the suffix effect involves the contributions of later processing stages and does not provide an uncontaminated index of preperceptual storage. In contrast, it is claimed that ABRM experiments provide the most direct index of the temporal course of perceptual recognition. Partial-report tasks and other paradigms are also evaluated in terms of their contributions to an understanding of preperceptual auditory storage. Differences between interruption and integration masking are discussed along with the role of preperceptual auditory storage in speech perception.

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Constipation is a frequent complaint among the elderly. Misconceptions about normal function and insistence on a daily bowel movement may be factors which have led to the overuse of laxatives. Evidence of gastrointestinal blood loss, a recent change in bowel elimination pattern or complications of constipation are indications for evaluation by complete laboratory, endoscopic and radiographic procedures. Natural fiber, careful attention to diet and fluid intake, regard for toilet needs and encouragement of activity are recommended as effective means for correcting constipation.

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The present experiments assessed the contribution of tone height, melodic contour, and tone chroma to melody recognition. Rather than using highly familiar folk songs as in earlier studies, subjects were taught new melodies. Novel melodies were used to (a) more precisely control potential cues (e.g., rhythm) that are not of present interest, (b) eliminate unison intervals that cannot be transformed appropriately, (c) provide a direct analysis of the nature of confusion errors, (d) test whether recently learned melodies are recognized differently than highly overlearned melodies, and (e) evaluate the extent to which practice in the experimental task alters the process of recognition. The results replicate previous studies using familiar folk songs. Transformations of the original melodies were accurately recognized when tone height was violated, but both melodic contour and tone chroma were maintained. Violating both tone height and contour while maintaining chroma produced extremely poor recognition. Performance was intermediate when just melodic contour was preserved. There is now good evidence to support the idea that melodic contour and tone chroma, in addition to tone height, contribute to recognition of both highly familiar and recently learned melodies.

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