Naturalistic memory in learning-disabled and skilled readers

Three experiments compared learning-disabled and skilled readers' performance on naturalistic memory measures, as well as investigated the relationship between memory performance on everyday and laboratory tasks. In Experiment 1, the laboratory task (sentence span task) and everyday memory measures were correlated moderately for both ability groups. Compared to skilled readers, disabled readers performed poorly on the sentence span task, and were less likely than skilled readers to remember information related to common objects and consequential events. Disabled readers were also less likely to rely on external prompts to help them recall everyday information. Experiment 2 extended the previous findings to older subjects and found that the majority of significant correlations between the laboratory (word span task) and everyday memory tasks were isolated to disabled readers. When compared to chronological-age-matched subjects, disabled readers were inferior in recency performance on the laboratory (word span) and natural serial recall (e.g., recall of U.S. presidents) tasks. Experiment 3 showed that under conditions that facilitate item accessibility, ability group differences in recall were comparable. Taken together, the findings indicate that disabled readers' memory deficits are pervasive across naturalistic and laboratory measures at the younger age, but these deficits diminish for older students. Further, the deficits that occur at the older age are due to problems in accessing knowledge.     

Taxi drivers' exceptional memory of street names

In this paper, we explore the nature of taxi drivers' serial recall of street names. The main question is whether the memory of verbal material benefits from the possibility of using visuospatial associations and knowledge concerning large-scale environment. In two experiments, expert taxi drivers' recall of street names was superior to that of control groups. In Experiment 1, experts' superiority of memory was greater when the street names reflected a visuospatially continuous route than when the street names were located along a straight line across the map without spatial continuity or were presented in random order. In Experiment 2, the expert taxi drivers recalled spatially continuously organized lists much better than they recalled lists of street names belonging to the same semantic category or lists presented in alphabetical order. This result also suggests that interitem associations, which are based on spatial co-occurrence, are efficient in comparison with other mnemonics.     

Individual differences in working memory capacity and episodic retrieval: examining the dynamics of delayed and continuous distractor free recall

Two experiments explored the possibility that individual differences in working memory capacity (WMC) partially reflect differences in the size of the search set from which items are retrieved. High- and low-WMC individuals were tested in delayed (Experiment 1) and continuous distractor (Experiment 2) free recall with varying list lengths. Across both experiments low-WMC individuals recalled fewer items than high-WMC individuals, recalled more previous list intrusions than high-WMC individuals, and recalled at a slower rate than high-WMC individuals. It is argued that low-WMC individuals' episodic retrieval deficits are partially due to the fact that these individuals search through a larger set of items than high-WMC individuals. Simulations based on a random search model were consistent with these general conclusions.     

The effect of increasing the memorability of category instances on estimates of category size

According to Tversky and Kahneman’s (1973) availability heuristic, people sometimes make use of the ease with which instances are retrieved when they have to estimate proportions or frequencies. One implication of this availability heuristic is that any factor that affects memorability of instances from a category should also affect the estimated category size. In one of their experiments, Tversky and Kahneman found that, after being presented with a list of names, people judged the more famous names to be more frequent. Similarly, recall was found to be greater for the more famous names. Three experiments that used Tversky and Kahneman’s paradigm are reported. Repeating nonfamous names resulted in their increased recallability and a corresponding increase in estimates of their frequency (Experiments 1 and 3). Making nonfamous names more salient (Experiment 3) also had parallel effects on recallability and frequency estimates, indicating that different memory manipulations affected availability in a similar fashion. Furthermore, reliance on the heuristic was not changed as a function of prior knowledge (Experiment 2) or practice (Experiment 3)     

Semantic and visual memory codes in learning disabled readers

Two experiments investigated whether learning disabled readers' impaired recall is due to multiple coding deficiencies. In Experiment 1, learning disabled and skilled readers viewed nonsense pictures without names or with either relevant or irrelevant names with respect to the distinctive characteristics of the picture. Both types of names improved recall of nondisabled readers, while learning disabled readers exhibited better recall for unnamed pictures. No significant difference in recall was found between name training (relevant, irrelevant) conditions within reading groups. In Experiment 2, both reading groups participated in recall training for complex visual forms labeled with unrelated words, hierarchically related words, or without labels. A subsequent reproduction transfer task showed a facilitation in performance in skilled readers due to labeling, with learning disabled readers exhibiting better reproduction for unnamed pictures. Measures of output organization (clustering) indicated that recall is related to the development of superordinate categories. The results suggest that learning disabled children's reading difficulties are due to an inability to activate a semantic representation that interconnects visual and verbal codes.     

Self-evaluation as a moderating factor of strategy change in directed forgetting benefits

In list method directed forgetting, instructing people to forget a studied word list usually results in better recall for a newly studied list. Sahakyan and Delaney (2003) have suggested that these benefits are due to a change in encoding strategy that occurs between the study of the first list and the study of the second list. To investigate what might mediate such strategy change decisions, in two experiments we induced bothforget and remember participants to evaluate their memory performance on the two lists. In Experiment 1, they were asked to explicitly recall the items from the first list before studying the second list. In Experiment 2, after the study of the first list, the participants provided a rapid aggregate judgment of learning. Evaluation eliminated the differences between the forget and remember groups for the second list in both experiments, because the remember group achieved recall levels comparable to those for the forget group. The role of performance evaluation in mediating directed forgetting benefits is discussed.     

Short-term memory in autism spectrum disorder

Three experiments examined verbal short-term memory in comparison and autism spectrum disorder (ASD) participants. Experiment 1 involved forward and backward digit recall. Experiment 2 used a standard immediate serial recall task where, contrary to the digit-span task, items (words) were not repeated from list to list. Hence, this task called more heavily on item memory. Experiment 3 tested short-term order memory with an order recognition test: Each word list was repeated with or without the position of 2 adjacent items swapped. The ASD group showed poorer performance in all 3 experiments. Experiments 1 and 2 showed that group differences were due to memory for the order of the items, not to memory for the items themselves. Confirming these findings, the results of Experiment 3 showed that the ASD group had more difficulty detecting a change in the temporal sequence of the items.     

Inadequacy of recall as a basis for frequency knowledge.

Subjects studied a word list comprising varying numbers of words from distinct semantic categories. The category names (trees, colors, etc.) were then re-presented, and for each name subjects either recalled as many exemplars as they could or estimated how many had been included in the list (Experiments 1 and 2). Recall was not sufficiently informative about actual category sizes to account for performance in the frequency estimation task. Moreover, it remained insufficiently informative when efforts were made to induce a recall-estimate strategy by requiring overt recall prior to estimation (Experiments 3-5), by using very small categories (Experiment 4), and by not showing the category name at study (Experiment 5), even though it did allow a partial account of estimation when the category exemplars were individually cued (Experiment 6). It is concluded that the role of recall in frequency estimation is much exaggerated.     

Individual differences in children's memory and reading comprehension: an investigation of semantic and inhibitory deficits

Three experiments compared the verbal memory skills of children with poor reading comprehension with that of same-age good comprehenders. The aims were to determine if semantic and/or inhibitory deficits explained comprehenders' problems on measures of verbal short-term memory and verbal working memory. In Experiment 1 there were no group differences on word- and number-based measures of short-term storage and no evidence that semantic knowledge mediated word recall. In Experiment 2 poor comprehenders were impaired on word- and number-based assessments of working memory, the greatest deficit found on the word-based task. Error analysis of both word-based tasks revealed that poor comprehenders were more likely to recall items that should have been inhibited than were good comprehenders. Experiment 3 extended this finding: Poor comprehenders were less able to inhibit information that was no longer relevant. Together, these findings suggest that individual differences in inhibitory processing influence the ability to regulate the contents of working memory, which may contribute to the differential memory performance of good and poor comprehenders.     

Recall as a self-limiting process

Presentation of only some category names as retrieval cues following presentation of a categorized list enhanced recall of the cued categories relative to free recall, but reduced recall of the noncued categories (Experiment 1). This recall interference from recall of cued categories increased with the number of category names presented (Experiment 2), and was not due merely to delaying the subject with an interfering interpolated task (Experiment 3). The results argue against theories assuming that categories are recalled via associations from previously recalled categories. Rather, the results suggest that recall of categories acts in a manner to limit recall of additional categories, in agreement with the characterization of recall as a sampling-with-replacement process as described by Rundus.     

Emotion and prior knowledge in memory and judged comprehension of ambiguous stories

Abstract

Two experiments investigated the effects of experimentally induced mood states on memory and judged comprehension of stories. The experiments examined the issue of whether induction of a depressed mood would affect prose memory and comprehension and impair the ability of individuals to use prior knowledge, activated by way of a title, in remembering the passage. In Experiment 1, depressed subjects who were given a title for the passage recalled fewer idea units when compared with neutral control conditions, but no depressive deficit in recall occurred in the absence of a title. In Experiment 2 the same pattern of results occurred when subjects learned two successive passages. The depressive deficits obtained were interpreted in terms of a resource allocation model which proposes that emotional states increase the production of irrelevant, competing thoughts that interfere with processes important in remembering the criterion passage. Alternative explanations involving cognitive initiative and schema theory were discussed. Finally, judgments of comprehension predicted passage recall and were better predictors for neutral than depressed mood subjects. A depressed mood state did not affect average judgments of comprehension even when recall was correspondingly impaired.     

Congruency effects in part-list cuing inhibition.

In demonstrations of part-list cuing inhibition, subjects who are shown a subset of studied list words recall fewer noncue words than subjects not shown such part-list cues. We propose that part-list inhibition is governed in part by an incongruency principle: Inhibition occurs to the extent that part-list cues induce a retrieval framework different from that used to encode list items. In Experiment 1, word lists were studied followed by a test of free recall either without cues, or with cue words serially organized to be either congruent or incongruent with the order of studied items. In Experiments 2-4, cues consisted of every second study item in the original presentation order (congruent ones) or reordered to form famous names or familiar idioms that had been hidden in the study list (incongruent cues). More part-list inhibition was observed with incongruent cues than congruent cues in all 4 experiments.     

Reinstating higher order properties of a study list by retrieving a list item

In two experiments, we looked at the role of higher order list properties in episodic recall. A probabilistic paired-associate paradigm was used in which each cue was repeatedly paired with two different targets. This paradigm permitted us to cue for a target that had been studied with that cue in the last list, or to cue for either of the two targets that had been repeatedly paired with that cue, although neither the cue nor either of its two targets had been studied in the last list. In Experiment 1, the higher order property was whether all of the targets in a given list were animal names or vegetable names. In Experiment 2, the higher order property was whether all of the pairs in a list were associatively related or unrelated. The assumption was that if participants were using these higher order properties when they retrieved a target that had been studied in the last list, they would also use these properties when recalling in response to a cue that had been studied in other lists but not in the most recent list. The results supported the use of both kinds of higher order properties in episodic access. They also showed that these higher order properties were reinstated by retrieving a target, and were then used in the next memory access operation. The questions of why the retrieval of a target would reinstate a higher order list property and how these very different higher order list properties aid in episodic access were also discussed.     

The effect of instructions to organize for good and poor learners

Two studies are reported which investigate the possibility that instructing individuals to organize their recall will differentially facilitate the performance of “fast” and “slow” learners (defined in terms of performance on a pretest). Experiment I utilized alphabetic organization in the free-recall learning of a list of unrelated words; Experiment II used a categorized word list under similar conditions. In each study, half of the individuals in each ability group received instructions, prior to the first of six learning trials, that contained information about the respective nature of organization present in the list and encouragement to use this type of organization in learning the list. In Experiment I, instructions to use alphabetic organization facilitated the performance of both ability groups to about the same extent. In Experiment II, instructions to use categorical organization in learning resulted in a substantial facilitation of performance for “slow” learners and a slight decrement in performance for “fast” learners. The results from the two studies are discussed in terms of sources of individual differences in learning.     

Examining the relationship between free recall and immediate serial recall: The serial nature of recall and the effect of test expectancy

In two experiments, we examined the relationship between free recall and immediate serial recall (ISR), using a within-subjects (Experiment 1) and a between-subjects (Experiment 2) design. In both experiments, participants read aloud lists of eight words and were precued or postcued to respond using free recall or ISR. The serial position curves were U-shaped for free recall and showed extended primacy effects with little or no recency for ISR, and there was little or no difference between recall for the precued and the postcued conditions. Critically, analyses of the output order showed that although the participants started their recall from different list positions in the two tasks, the degree to which subsequent recall was serial in a forward order was strikingly similar. We argue that recalling in a serial forward order is a general characteristic of memory and that performance on ISR and free recall is underpinned by common memory mechanisms.     

Estimating national populations: cross‐cultural differences and availability effects

Estimates of national population were studied in two experiments. In Experiment 1, Canadian and Chinese undergraduates rated their knowledge of 112 countries and then estimated the population of each. In Experiment 2, Canadians rated their knowledge of 52 countries and then provided population estimates for these primed countries and for a comparable set of 52 unprimed countries. In Experiment 1, participants from both nations produced estimates that resembled those obtained from Americans in prior studies (Brown and Siegler, 1992 , 1993 , 1996 , 2001 ). However, there were several reliable cross‐national differences in performance which appear to reflect cross‐cultural differences in task‐relevant naive domain knowledge. In addition, both experiments produced findings consistent with the claim that availability‐based intuitions play an important role in this task. In Experiment 1, cross‐national differences in rated knowledge predicted cross‐national differences in estimated population; in Experiment 2, primed country names elicited larger population estimates than unprimed country names. We conclude by arguing for the general utility of this hybrid approach to real‐world estimation. Copyright © 2002 John Wiley & Sons, Ltd.     

The Name-Pronunciation Effect: Further Evidence from Chinese

This study examined the Chinese name-pronunciation effect. The easy-to-pronounce and difficult-to-pronounce Chinese names were created using the same characters in order to control for visual perceptual and conceptual fluency. In Experiment 1, participants rated each name in terms of liking, electability as a state leader, income level, and baby name preference. An additional rating of prevalence was used to estimate familiarity. In Experiment 2, participants did not read the name aloud before rating and performed intentional recall and recognition tests. In both experiments, the easy-to-pronounce names were rated higher than difficult-to-pronounce names on liking. This effect generalized to judgments of electability and baby name preference but not to prevalence and income level. There were no differences in memory performances between the two types of names. Results are discussed in terms of the boundary condition of the name-pronunciation effect and the advantage of using Chinese names to study this effect.     

Cued vs. free recall in long-term memory of the fifty united states

Subjects were asked to recall the names of the fifty United States under varied conditions. These conditions included free recall and cued recall. The recall of the fifty United States was poorer than expected for college students. The average recall was approximately 41 out of 50 states. When subjects were asked to fill in the names of the states on a blank map, recall dropped to approximately 32 out of 50 states. It appears that subjects can recall some states better than others. For example, recall is better for states in close proximity to a subject’s current residence. Perhaps subjects have a geographic bubble when it comes to recalling the names of the states.     

Global Predictions of Memory in Alzheimer’s Disease: Evidence for Preserved Metamemory Monitoring

Previous researchers have argued that there is a metamemory monitoring deficit in Alzheimer’s disease (AD) because patients tend to overestimate their recall performance on a word list. We propose that these previous results are a misleading by-product of the methodologies used, rather than evidence of an underlying metamemory deficit. In two experiments, AD patients and older adult controls made predictions of performance both before and after encoding a to-be-remembered list. Metamemory function was measured by observing the shift in predictions made with, and without, an opportunity to monitor the list. Experiment 1 found that although there were differences between the groups’ accuracy for their prestudy predictions of recall, both groups were equally accurate after encoding. Experiment 2 explored this using four lists that varied in item difficulty and semantic relatedness. This experiment replicated the findings of Experiment 1, and it was also found that the AD group became more accurate at predicting their performance with more exposure to study-test trials. These studies suggest that metamemory monitoring is intact in AD, because AD patients utilize information gained during processing the to-be-remembered items to revise their predictions of subsequent performance.     

What it costs to implement a plan: Plan-level and task-level contributions to switch costs

Four experiments were conducted to identify the costs of implementing a plan in the task span procedure, which requires subjects to retrieve the task to perform on the current target from a list of planned tasks in memory. Experiment 1 compared switch costs in the task span procedure with switch costs in the explicit task-cuing procedure, which presented cues indicating the task to perform on each target. Switch costs were greater in the task span procedure. Experiments 2-4 were designed to identify the sources of this difference. Experiment 2 showed that the requirement of establishing a correspondence between the list of task names and the list of targets contributed to switch costs. Experiment 3 showed that retaining lists of similar task names produced greater switch costs than did retaining lists of dissimilar task names. Experiment 4 showed that memory load had no effect on switch costs. The results are discussed in terms of the interaction between plan-level and task-level processing in the implementation of plans.