Automatic encoding of superordinate and subordinate taxonomic categories in different populations.

Utilized D. D. Wickens's (1970) release from proactive interference (PI) task to assess automatic conceptual encoding at both the superordinate and subordinate category levels in 2 populations. Ss were 2nd and 4th graders from a low-socioeconomic-status Black community and 2nd and 4th graders from a middle-class White community. The principal factors in the study were list (superordinate: animals and foods; Subordinate 1: birds and mammals; Subordinate 2: fruits and vegetables), population, grade level, and condition (control vs shift) as between-Ss factors and trials (1–4) as a within-Ss factor. 48 children from each population and grade level served as Ss for each list. Results indicate significant PI build-up for all Grade?×?Population combinations on the 3 lists, with the exception of the 2nd graders on the superordinate list. Release from PI was observed at the 4th-grade level on the superordinate list and at both grade levels on Subordinate List 1 (birds and mammals). Generally speaking, reliable differences between the 2 populations in PI build-up and/or release were not detected. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory and learning strategies in patients with Parkinson's disease

Parkinson's disease patients (PD) do not differ from control subjects (CS) when they have to execute a problem solving task in which external cues for solving the problem are given. However, when PD have to solve a problem by means of an internally generated strategy, they show a serious decrease in performance. We hypothesised that this distinction may also apply to the way PD and CS organize recall. In order to test our hypothesis the California Verbal Learning Test (CVLT) was administered to 59 PD and 30 CS. The test consists of five learning trials using a 16-word target list, composed of four items from each of four semantic categories. The fact that the word list was built on this implicit organization was not divulged in advance. The sequence in which the words were read is fixed; each subsequent word belongs to a category being different from the category to which the preceding word belongs. The organization in recall according to the semantic categories is considered to be the result of an unprompted, internally generated strategy. Recall according to the sequence in which the words are read by the experimenter, is viewed as an externally offered strategy. The results prove to be in line with our hypothesis: unlike CS who appeared to rely mainly and increasingly on an internally generated semantic organization, PD showed evidence of gradually adhering more to the externally imposed serial sequence.     

Age differences in proactive interference, working memory, and abstract reasoning.

[Correction Notice: An erratum for this article was reported in Vol 23(4) of Psychology and Aging (see record 2008-19072-007). The original article contained an incorrect DOI. The correct DOI is as follows: 10.1037/a0012577.] It has been hypothesized that older adults are especially susceptible to proactive interference (PI) and that this may contribute to age differences in working memory performance. In young adults, individual differences in PI affect both working memory and reasoning ability, but the relations between PI, working memory, and reasoning in older adults have not been examined. In the current study, young, old, and very old adults performed a modified operation span task that induced several cycles of PI buildup and release as well as two tests of abstract reasoning ability. Age differences in working memory scores increased as PI built up, consistent with the hypothesis that older adults are more susceptible to PI, but both young and older adults showed complete release from PI. Young adults' reasoning ability was best predicted by working memory performance under high PI conditions, replicating M. Bunting (2006). In contrast, older adults' reasoning ability was best predicted by their working memory performance under low PI conditions, thereby raising questions regarding the general role of susceptibility to PI in differences in higher cognitive function among older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive resources and dual-task interference effects at retrieval in normal people: The role of the frontal lobes and medial temporal cortex.

Conducted 3 experiments to examine the hypothesis that concurrent secondary tasks at retrieval will interfere more with long-term, episodic memory functions involving the frontal lobes than those involving the medial temporal lobes hippocampus (MTL/H). The rationale is that strategic retrieval processes mediated by the frontal lobes place greater demands on cognitive resources than do relatively automatic associative retrieval processes (ecphory) mediated by the temporal lobes. In Exps 1 and 2, sequential finger tapping was performed at encoding, at retrieval, at both, or at neither. Recall of a categorized list of 16 words from the California Verbal Learning Test in Exp 1, and release from proactive inhibition (PI) in Exp 2, both being tests that involve the frontal lobes, were impaired if normal Ss tapped at both encoding and retrieval. Concurrent tapping had little effect on rate of learning in Exp 1 and on total words recalled during the buildup of PI in Exp 2, both of which are indices that are affected more by MTL/H than by frontal lesions. In Exp 3, tapping by normal Ss affected letter fluency, a test more sensitive to frontal lobe than temporal lobe damage, but not category fluency, for which the reverse is true. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Control of pigeons' spatial search by graphic landmarks in a touch-screen task.

Pigeons learned to peck an unmarked 2-cm–2 target area, defined by 4 visually distinct graphic landmarks, on a color monitor with an attached touch frame. The configuration of landmarks and target area was constant during training, but their location on the screen varied across trials. The presence, relative location, and features of the landmarks were manipulated on probe trials. Most birds showed control by only 1 or 2 of the landmarks, and some birds displayed surprisingly accurate search with a single landmark. For individual birds, landmark-removal tests were very consistent with landmark-shift tests in indicating which landmark or landmarks controlled search. However, the dominant landmark varied across birds. Manipulation of landmark color and shape revealed that control was based exclusively on color. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Proactive interference and the dynamics of free recall.

Proactive interference (PI) has long been recognized as a major cause of forgetting. Two experiments were conducted that offer another look at the subject by providing a detailed analysis of recall latency distributions during the buildup of and release from PI. These functions were accurately characterized by the convolution of the normal and exponential distributions (viz., the ex-Gaussian), which previously has been shown to describe recognition latency distributions. Further, the fits revealed that the increase in recall latency associated with the buildup of PI results from a slowing of the exponential retrieval stage only. The same result was found even when a short retention interval was used (and recall probability remained constant). These findings suggest that free-recall latency may be a sensitive index of the increased search set size that has often been assumed to accompany the buildup of PI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correction to Emery, Hale, and Myerson (2008).

Reports an error in "Age differences in proactive interference, working memory, and abstract reasoning" by Lisa Emery, Sandra Hale and Joel Myerson (Psychology and Aging, 2008[Sep], Vol 23[3], 634-645). The original article contained an incorrect DOI. The correct DOI is as follows: 10.1037/a0012577. (The following abstract of the original article appeared in record 2008-13050-014.) It has been hypothesized that older adults are especially susceptible to proactive interference (PI) and that this may contribute to age differences in working memory performance. In young adults, individual differences in PI affect both working memory and reasoning ability, but the relations between PI, working memory, and reasoning in older adults have not been examined. In the current study, young, old, and very old adults performed a modified operation span task that induced several cycles of PI buildup and release as well as two tests of abstract reasoning ability. Age differences in working memory scores increased as PI built up, consistent with the hypothesis that older adults are more susceptible to PI, but both young and older adults showed complete release from PI. Young adults' reasoning ability was best predicted by working memory performance under high PI conditions, replicating M. Bunting (2006). In contrast, older adults' reasoning ability was best predicted by their working memory performance under low PI conditions, thereby raising questions regarding the general role of susceptibility to PI in differences in higher cognitive function among older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term proactive interference and novelty enhancement effects in monkey list memory.

Serial-probe-recognition (SPR) performance by 2 monkeys deteriorated over several months of training. Three hundred and twenty different items were presented without repetition within a session (trial unique) but were repeated between sessions. The cause of the deterioration was identified as proactive interference (PI) due to repetitive use of items from day to day. Introduction of novel stimuli across days improved performance from 63% to 82% correct (Experiment 1). Tests with only probe items and no list items (Experiment 2) revealed that the monkeys were using a familiar/novel response strategy in combination with a relational strategy (relating the probe item to the list items) to further improve their SPR performance. Intermixing familiar baseline trials and novel transfer trials within a session (Experiment 3) encouraged the subjects to use a relational strategy, and it improved performance on baseline trials as well as on transfer trials. Possible qualitative similarity between the relational strategy and the familiar/novel response strategy is discussed along with theoretical implications of these findings for experiments which have used small number of repeating stimuli within a session. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contextual cues and release from proactive inhibition in young and old people.

Three experiments examined whether elderly people perform similarly to Korsakoff amnesics on tests of release from proactive inhibition (PI). In Exp I, with 20 18–36 yr old undergraduates, 20 64–77 yr old university alumni, 20 employed 21–43 yr olds, and 21 institutionalized but healthy 71–92 yr olds, only the latter Ss failed to release from PI, like Korsakoff amnesics, whereas all the other groups of Ss showed the normal release from PI. Exp II, with 12 institutionalized 64–90 yr olds and 12 25–47 yr old controls, showed that release from PI could be induced in institutionalized elderly, as in Korsakoff amnesics, by salient environmental cues that coincided with the category shift. Exp III, with 13 67–89 yr old institutionalized Ss and 12 22–42 yr old controls, demonstrated that even in the absence of a category shift, salient environmental cues could lead to smaller, but noticeable, release from PI in institutionalized elderly, but not in young controls. The similarity in performance between the institutionalized elderly and Korsakoff amnesics suggested that it results from a common neurological deficit. (French abstract) (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial organization and prior free recall.

Assessed serial recall and organization of a list after different levels of prior free-recall learning with the same list. Performance was expected to be impaired as a direct function of amount of free recall because of inappropriate organizational units formed during free recall. Recall on serial trials following 15 free-recall trials was inferior to 5 or 10 prior free-recall trials. 4 groups of 24 Ss each were tested. Serial organization on the 1st serial trial was inferior if prior free recall occurred, but did not vary with the amount of free recall. These results, and those of part-whole and whole-part free-recall transfer studies, were interpreted by a component analysis of free recall, including response learning/unlearning and organizational learning/unlearning. (16 ref.) (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for proactive interference in the focus of attention of working memory.

Proactive interference (PI) occurs when an earlier item interferes with memory for a newer item. Whereas some researchers (e.g., Surprenant & Neath, 2009a) argue that PI can be observed in all memory systems, some multiple systems theorists (e.g., Cowan, 1999) propose that items in the focus of attention of working memory are immune to PI. Two experiments tested whether PI occurs when the to-be-remembered items are assumed, by multiple-systems theorists, to be held in the focus of attention. In each experiment, subjects saw four trials in a row with the same type of to-be-remembered items, followed by four trials in a row with a different type of material. On each trial, only 3 stimuli were shown, which is below the capacity limit of the focus of attention, and subjects were asked if a probe item was one of those 3 items seen. In both experiments, response time increased from Trial 1 to Trial 4, suggesting that items from the earlier trials interfered with memory on the later trials. In addition, release from PI was shown in that response times decreased with a change of materials. The results replicate those first reported by Hanley and Scheirer (1975), and pose a problem for theorists who argue that parts of short-term memory are immune to PI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Primacy and recency effects in rhesus monkeys (Macaca mulatta) using a serial probe recognition task: II. Effects of atropine sulfate.

Nonhuman primates display both a primacy and a recency effect when trained on a 6-item serial probe recognition task. The author has previously shown that, in the rhesus monkey, diazepam (3.2 mg/kg im) interferes with the memory processes that mediate the recency effect without affecting those memory processes involved in the primacy effect (C. A. Castro, 1995). This study assessed the effects of atropine sulfate (0.2, 0.3, and 0.4 mg/kg im) on the primacy and recency effects in these same monkeys. Opposite the effects of diazepam, atropine disrupted the primacy component of the serial position curve and had no measurable effect on the recency component. In addition, the 2 highest doses of atropine disrupted accuracy on the nonmatching probe trials, whereas all 3 doses of atropine resulted in increased response latencies. These reports indicate that the primacy and recency effects in the nonhuman primate can be pharmacologically dissociated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of same-category and different-category extraneous memory sets on item recognition

In a study designed to distinguish between parallel and serial models of performance on Sternberg's item recognition task, Krueger (1975) presented subjects with a memory set (the "added" set) followed by a second ("core") set, a probe to the core set, and finally a probe to the added set. Response latency (RT) to both the core- and added-set probes initially increased with the size of the extraneous set. Over successive blocks of trials, the effect of the size of the extraneous set diminished. In Experiment 1 of the present study, Krueger's basic procedures were replicated with results similar to those he reported for early trials. Experiment 2 was a variation on the added-set procedure. Rather than the memory sets' being drawn from different categories (letters and digits), both sets consisted of digits. On half of the negative trials for both the core and the added tasks, the probe was drawn from the extraneous set, forcing the subjects to separate the two sets. Although RT on the core task did not increase with the size of the added set, there was an increase in RT to the added set with increases in core-set size, a finding inconsistent with the serial search model.     

Proactive interference and item similarity in working memory.

Proactive interference (PI) may influence the predictive utility of working memory span tasks. Participants in one experiment (N=70) completed Ravens Advanced Progressive Matrices (RAPM) and multiple versions of operation span and probed recall, modified for the type of memoranda (digits or words). Changing memoranda within- or across-trials released PI, but not doing so permitted PI buildup. Scores from PI-build trials, but not PI-release trials, correlated with RAPM and accounted for as much variance in RAPM as unmodified tasks. These results are consistent with controlled attention and inhibition accounts of working memory, and they elucidate a fundamental component of working memory span tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Working-memory capacity, proactive interference, and divided attention: Limits on long-term memory retrieval.

Two experiments examined how individual differences in working-memory capacity (WM) relate to proactive interference (PI) susceptibility. We tested high and low WM-span participants in a PI-buildup task under single-task or dual-task ("load") conditions. In Experiment 1, a finger-tapping task was imposed during encoding and retrieval of each list; in Experiment 2, tapping was required during encoding or retrieval. In both experiments, low spans showed greater PI than did high spans under no load, but groups showed equivalent PI under divided attention. Load increased PI only for high spans, suggesting they use attention at encoding and retrieval to combat PI. In Experiment 2, only low spans showed a dual-task cost on List 1 memory, before PI built up. Results indicate a role for attentional processing, perhaps inhibitory in nature, at encoding and retrieval, and are discussed with respect to theories of WM and prefrontal cortex function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cyclic responding by pigeons on the peak timing procedure.

The present experiment examined whether discrimination learning shapes the single-peaked response distributions usually obtained with the peak procedure. Two sources of learning in pigeons were disclosed: learning to respond near the time of reinforcement on fixed interval (FI) trials and learning to withhold responding once the FI duration had elapsed on peak interval (PI) trials. Pigeons also produced a highly unexpected second peak in responding on nonreinforced PI trials at 3 times the FI duration. Follow-up experiments showed that a 1:4 FI:PI duration ratio supported double peaks, but only 1 peak was obtained with a 1:8 FI:PI duration ratio. Finally, 4 peaks could be observed on extra-long PI trials under a 1:4:8 FI:PI:PI ratio procedure. The multiple-peaked response distributions are an unprecedented finding that present a major challenge to any theory of time perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial position effects in recognition memory for odors.

Five experiments examined recognition memory for sequentially presented odors. Participants were presented with a sequence of odors and then had to identify an odor from the list in a test probe containing 2 odors. All experiments demonstrated enhanced recognition of odors presented at the start and end of a series, compared with those presented in the middle of the series when a 3-s retention interval between list termination and test was used. In Experiments 2 and 3, when a 30-s or 60-s retention interval was used, participants performed at slightly lower levels, although the serial position function was similar to that obtained with the 3-s retention interval. These results were noted with a 5-item (Experiments 1 and 4), 7-item (Experiment 2), 6-item (Experiment 3), and 4-item (Experiment 5) list of odors. As the number of test trials increased, recognition performance decreased, indicating a strong role for olfactory fatigue or interference in these procedures. A verbal suppression task, used in Experiments 4 and 5, had little influence on serial-position-based performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of adult age on primary and secondary memory search.

Conducted 2 experiments with 25 19–29 yr olds, 26 62–85 yr olds, 30 18–32 yr olds, and 30 61–81 yr olds to compare young and elderly adults on the ability to search lists of words stored in primary memory (PM) and in secondary memory (SM). Exp I indicated that age differences in search performance were greatest under SM conditions. Older Ss, unlike the younger ones, appeared biased toward responding that probe items were not members of the memory sets stored in SM. As a result of this apparent bias, older Ss committed a large number of errors on trials in which the probe was a member of the memorized list (i.e., positive probe trials) yet few errors on the trials in which the probe was not a member of the list ( i.e., negative probe trials). The responses of older Ss to negative probe trials were more rapid than were those to positive probe trials. In Exp II, this pattern of responding was examined. It is concluded that age differences were involved in the ability to encode memory sets and transfer them from PM to SM as well as in the ability to retrieve information from SM prior to conducting a memory search. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial recall versus recall by categories in short-term memory.

C. G. Penney (1980) reported that serial recall of a list containing both auditorily and visually presented verbal items produced a lower level of recall than did separate recall of auditory and visual items. This finding was interpreted as support for the hypothesis that auditory and visual items are processed in separate streams in short-term memory, and that it is difficult to integrate these 2 streams into 1 sequence for rehearsal. The present study tested an alternate interpretation of the earlier results, the hypothesis that retention of order information is facilitated by S's being able to organize the list into 2 short sequences rather than 1 long sequence. Three experiments (72 university students) were carried out in which spatial location or category of stimulus material (letters or digits) was used to establish 2 types of items. Total recall from a list did not differ significantly between the serial and category recall conditions. Results rule out the organizational interpretation of the bisensory experiment and, therefore, provide indirect support for the separate streams hypothesis. (French abstract) (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)