Vocalization-at-presentation and immediate recall, with varying presentation-rates

An experiment is reported in which the subject read visually presented lists with four different degrees of vocalization; immediately after reading each list he was required to reproduce it either aloud or in writing. Each list consisted of eight consonants and presentation rates were varied between I and 4 letters per sec. For any given series of lists, the subject was asked either to read the letters silently, or to mouth them silently, or to whisper them, or to say them aloud while reading.

At the fastest presentation-rate immediate recall improved monotonically with the degree of vocalization during reading of the lists; at slower rates this generalization held less well, especially for the lower degrees of vocalization. Vocalization was most helpful at the highest presentation-rate.

The overall amount correctly recalled was better for more slowly presented lists and for written as opposed to spoken recall. Analysis of the errors suggested that acoustic confusions were affected by the conditions of presentation; and that serial order intrusions were independent of presentation-or recall-conditions. An apparent variation of transpositions with voicing-and-recall-method failed to reach statistical significance. Theoretical implications of the experiment are discussed, including reference to Broadbent's theory of short-term memory (1958).     

Dissociations between procedural and episodic memory: effects of time and aging

The issue of multiple memory systems is explored. Young and older adults (mean ages = 20 and 71, respectively) named pictures and were tested immediately, 1, 7, or 21 days later. Episodic memory (recognition) for pictures was significantly lower in older relative to young adults and declined systematically across all retention intervals in both age groups. In contrast, procedural memory (repetition priming in picture naming) revealed no reliable age differences. In both age groups, priming declined within the first 24 hr, but unlike recognition, there was no further decrement from 1 to 21 days. There were also within-subject dissociations: The magnitude of priming was equivalent for remembered and forgotten items, and the relation between recognition and priming across intervals was nonmonotic, revealing a reversed association. The findings were interpreted within a multiple-memory-systems framework.     

Adult age comparisons in the processing of event frequency information

The usual superiority in frequency-of-occurrence judgments of younger vs. older subjects was hypothesized to result from greater strategic encoding of the materials conveying frequency information. A subject-paced, visual search task was designed to control nontarget word encoding. Relative frequency judgments for the nontarget word pairs were equally accurate for younger and older subjects, and performance of both groups was above chance. Results suggest that strategic cover-task encoding can induce age differences in incidental frequency processing. Consistent with a nonoptimal as opposed to an optimal view, automatic processes require only minimal capacity for above-chance performance, but additional strategic resources can increase performance. When such additional resources are used more by younger than by older subjects, the former are better in frequency performance.     

Preserved organization of semantic attributes in Alzheimer's disease

This study investigated whether Alzheimer's disease (AD) disrupts the basic organization of the semantic attributes of concepts. Young and normal older subjects and AD patients were presented with a target concept followed by a stimulus word and were to decide whether the stimulus was related to the target. On those trials where it was, the stimulus was either a high-, medium-, or low-dominance attribute of the target. The higher the normative dominance, the more important the attribute to concept meaning. In all 3 subject groups, decision time varied as a function of dominance. The higher the dominance, the faster the decision. Attribute dominance affected the performance of AD patients more than that of normal subjects. These results suggest that AD patients retain their knowledge of the relative importance that the different attributes of a concept have for concept meaning.     

Retrospective assessment of marital adjustment and depression during the first 2 years of spousal bereavement

Two hundred twelve bereaved elders rated marital adjustment using items drawn from the Locke and Wallace (1959) Marital Adjustment Test and completed the Beck Depression Inventory 2 months, 12 months, and 30 months after the loss of their spouses. Their responses were compared with those of 162 nonbereaved individuals of comparable age who were tested at the same times. More positive ratings of marital adjustment were made by bereaved subjects than by nonbereaved subjects. Among nonbereaved elders, more severe ratings of depression were associated with lower ratings of marital adjustment. In the bereaved sample, however, the opposite was found: More severe ratings of depression were associated with higher ratings of marital adjustment. This pattern of results changed only slightly over the 2.5-year course of bereavement and was not influenced by gender. These results are discussed in terms of cognitive processes (e.g., idealization) that influence retrospective assessments of marital adjustment during bereavement.     

Systematic 24-hr behavioral observations of sleep and wakefulness in a skilled-care nursing facility

Sleep patterns of aged, infirm, demented, chronically institutionalized residents of a skilled-care nursing facility were studied. The purpose of this naturalistic study was to describe sleep and wakefulness (S/W) within the limits afforded by brief behavioral observations and to examine homeostasis and diurnal rhythmicity of S/W as a function of psychoactive drug intake. Observers noted S/W every 15 min, 24 hr a day for 10 days in 24 Ss. Results indicated substantial individual variation in daytime hours. Daily and weekly variation within Ss was minimal. Sleep was least likely near sunset. Ss on psychoactive drugs showed dampened diurnal variation in S/W rhythms. In Ss not on such drugs, there was a suggestion of homeostasis of S/W between sleep during the morning and evening hours. Results are discussed methodologically (viability of approach), theoretically (age-related change in sleep), and practically (potential treatments).     

Cognitive complaints in elderly depressed and pseudodemented patients

The cognitive complaints of 11 patients with depressive pseudodementia were compared with those of 22 patients with depression alone. Pseudodemented subjects were defined as depressed inpatients showing reversible cognitive impairment as measured by the Mini-Mental State Examination (MMSE); subjects with depression alone had no such impairment. For each group, cognitive complaints were highly correlated with depressive symptoms and were not related to MMSE scores. The pseudodemented group had significantly higher cognitive complaint scores, complaining more of difficulties with concentration and recent memory. Groups did not differ significantly in complaints of difficulties with remote memory.