Learning in a unidimensional absolute identification task

We tested whether there is long-term learning in the absolute identification of line lengths. Line lengths are unidimensional stimuli, and there is a common belief that learning of these stimuli quickly reaches a low-level asymptote of about seven items and progresses no more. We show that this is not the case. Our participants served in a 1.5-h session each day for over a week. Although they did not achieve perfect performance, they continued to improve day by day throughout the week and eventually learned to distinguish between 12 and 20 line lengths. These results are in contrast to common characterizations of learning in absolute identification tasks with unidimensional stimuli. We suggest that this learning reflects improvement in short-term processing.     

Inhibitory processes in young and older adults in a picture-word task

Abstract

The present study examines changes in healthy young and healthy older adults in the ability to inhibit partially activated information in a picture/word interference paradigm. On each trial, subjects received a cue (i.e., the word PICTURE or WORD) indicating which of two stimuli the subject should attend to in an upcoming picture/word display. the display always contained a superimposed picture and word (e.g., a picture of a DEER with the word TEA printed on it). Following display offset, and depending upon the initial precue, either a test picture (e.g., KETTLE) or a test word (e.g., MOOSE) was presented. the subject's task was to determine as quickly and as accurately as possible whether the test stimulus was related to the cued dimension of the earlier picture/word display. the speed to reject an unrelated test item (e.g., picture of a KETTLE when the precue was PICTURE) that was related to the ignored dimension of the picture/word display (e.g., the word TEA in the picture/word display) was used as an index of the efficiency of the inhibitory system. the results indicated that older adults had more difficulty than younger adults inhibiting a to-be-ignored word when it was related to a picture test item, but did not have more difficulty inhibiting a to-be-ignored picture when it was related to a word test item. the results indicate that an age-related deficit in the control of interfering information is dependent upon the fluency of the processing routes.     

Choice and response time processes in the identification and categorization of unidimensional stimuli

Lacouture and Marley (1991, 1995, 2001) have successfully modeled the probabilities of correct responses and the mean correct response times (RTs) in unidimensional absolute identification tasks for various stimulus ranges and stimulus/response set sizes, for individual and group data. These fits include those to a set of phenomena often referred to as end-anchor effects. A revised model, with the independent accumulator decision process replaced by a leaky competing accumulator decision process, fits the probabilities of correct responses and the full distributions of RTs in unidimensional absolute identification. The revised model is also applied successfully to a particular class of unidimensional categorization tasks. We discuss possible extensions for handling sequential effects in unidimensional absolute identification, and other extensions of the given class of categorization tasks that are of potential empirical and theoretical importance as a supplement to the study of multidimensional absolute identification tasks.     

Improving time discrimination in children and adults in a temporal bisection task: The effects of feedback and no forced choice on decision and memory processes

In children aged 5 and 8 years old as well as in adults, Experiment 1 tested the effect of feedback on temporal performance using a bisection task. Experiment 2 added a no-forced-choice condition by giving the participants the possibility of responding “I don't know”. The results of Experiment 1 showed that providing feedback increased the bisection point value (point of subjective equality) in all age groups and increased sensitivity to time in the youngest children. The results of Experiment 2 showed that the proportion of “I don't know” responses peaked at the probe duration close to the arithmetic mean of the two anchor durations and decreased as the distance from this central value increased in both the adults and the 8-year-olds. In the 5-year-olds, the proportion of “I don't know” responses was lower and remained constant whatever the probe duration values. Unlike in the youngest children, giving the adults and the 8-year-olds the opportunity to respond “I don't know” increased their sensitivity to time. The modelling of our data suggests that providing feedback in a temporal bisection task affects both the memory and the decision processes. However, whereas the feedback-related effect had a similar effect on decision processes across the age groups, it had an opposite effect on memory processes in the 5-year-olds and the older participants, decreasing the variability of the memory representation of the anchor durations in the former while increasing it in the latter. Finally, in bisection, feedback only improved temporal performance when the memory for duration was imprecise as in the case of the children.     

Orienting task effects on memory for presentation modality in children, young adults, and older adults.

Children (7 to 10 years), young adults (17 to 24 years), and older adults (55 to 77 years) were asked to learn three lists of words that were of mixed modality (half the words were visual, and half the words were auditory). With one list the subjects were asked a semantic orienting question; with another, a nonsemantic orienting question; and with a third, no orienting question. Half the subjects in each age group were also asked to remember the presentation modality of each word. Older adults remembered less information about modality than children and young adults did, and the variation in the type of orienting question--or the lack of one--affected modality identification. However, there was no Orienting Task x Age interaction for modality identification. The results of this study suggest that encoding modality information does not take place automatically--in any age group--but that explanations focusing on encoding strategies and effort are not likely to account for older adults' difficulties in remembering presentation modality.     

Relationships between metamemory, memory predictions, and memory task performance in adults

A cross-sectional sample of adults recalled categorized word lists and narrative texts. Subjects gave performance predictions before each of 3 recall trials for each task. Older subjects had poorer memory performance and also predicted lower performance levels than did younger subjects. The LISREL models suggested (a) direct effects of memory self-efficacy (MSE) on initial predictions; (b) upgrading of prediction-performance correlations across trials, determined by direct effects of performance on subsequent predictions; (c) significant effects of a higher order verbal memory factor on MSE; and (d) an independent relationship of text recall ability to initial text recall performance predictions. These results lend support to the theoretical treatment of predictions as task-specific MSE judgments.     

Dissociating automatic and controlled processes in a memory-search task: Beyond implicit memory

Our goal in this paper was to examine the processes that give rise to action slips. Procedures used to examine implicit memory and automatic processes were found to be unsatisfactory. However, the process-dissociation procedure proved useful for examining the contribution of the automatic and controlled processes underlying performance. The procedure was used in conjunction with a Sternberg memory-search task to examine the effects of set size, response speed, and stimulus-response mapping on controlled and automatic processes. The formulation allowed us to predict accurately how subjects would perform in a varied mapping condition. Moreover, set size and response speed were found to influence the controlled search process, but to leave the automatic influences unaffected. Stimulus-response mapping, on the other hand, was found to lead to probability matching in the automatic processes; this pattern was found to remain constant across changes in set size and response speed.     

Attention and memory cues in concept learning as a function of task complexity and age

The effects of attention and memory cues on concept learning performance were investigated as a function of task complexity and grade level of Ss. It was found that: (1) the attention and memory cues were closely interrelated in their effects upon performance with both significantly improving performance at all but the lowest levels of complexity; (2) both types of cues considerably lessened the effect of stimulus complexity upon performance; and (3) the attention cue elicited the best performance from Ss in the first through ninth grades, while the memory cue elicited the best performance from 4-year-old and kindergarten Ss.     

Age and task effects in short-term memory of children

Children of 4, 8, and 14 years performed a visual memory task with easy- or hard-to-label displays and with or without repetition of stimuli over trials. Eight pictures were displayed in serial order, and the task was to find the card in the array that matched an identical probe card. Performance improved with age, and strong serial position effects were obtained for all ages and tasks. In contrast to previous studies, primacy effects were obtained for the youngest children tested. Task difficulty increased with difficulty of labeling and with repetition, but order of task difficulty remained the same for all ages. The d’ measure, borrowed from signal detection theory, revealed differences in criterion levels over serial position, which in earlier studies had been confounded with strength of memory.     

False memory in a short-term memory task

The Deese/Roediger-McDermott (DRM; Roediger & McDermott, 1995) paradigm reliably elicits false memories for critical nonpresented words in recognition tasks. The present studies used a Sternberg (1966) task with DRM lists to determine whether false memories occur in short-term memory tasks and to assess the contribution of latency data in the measurement of false memories. Subjects studied three, five, or seven items from DRM lists and responded to a single probe (studied or nonstudied). In both experiments, critical lures were falsely recognized more often than nonpresented weak associates. Latency data indicated that correct rejections of critical lures were slower than correct rejections of weakly related items at all set sizes. False alarms to critical lures were slower than hits to list items. Latency data can distinguish veridical and false memories in a short-term memory task. Results are discussed in terms of activation-monitoring models of false memory.     

Use of landmark features and geometry by children and adults during a two-dimensional search task

Three- to six-year-old children (n = 28) and adults (n = 46) participated in a two-dimensional search task that included geometry and feature conditions. During each of 24 trials, participants watched as a cartoon character hid behind one of three landmarks arranged in a triangle on a computer screen. The landmarks and character then disappeared and reappeared in the same or a new position on the screen. During feature condition trials participants could use unique features of the landmarks to locate the hidden character, while during geometry trials participants could only use the geometry of the triangle. In both conditions, adults’ performance was near ceiling while children’s performance was significantly worse. Children’s performance was worse in the geometry condition than in the feature condition but search accuracy improved with age for both types of information. Findings are considered in the context of the broader literature on spatial cognition and development.     

Alternative theories of concept identification among older adults

The purpose of the present experiment was to investigate some predictions of hypothesis testing and S-R association (frequency) theories regarding memory for intratrial events on a conjunctive concept-identification task. They have received extensive study with young adults but not with older subjects. The individual events under investigation were feedback, responses, hypotheses, and stimuli. Hypothesis-testing theory requires subjects to retain information concerning the correct hypothesis from one trial to the next whereas frequency does not. 75 subjects (60-70 yr. old) participated in the study. Subjects had difficulty in recalling the correct hypothesis stated on previous trials. These errors occurred on problems with negative response trials, not with incorrect feedback. The results contradict predictions based on hypothesis-testing models but are consistent with frequency theory. Unlike in the studies based on younger adults, present subjects did not recall the hypothesis very well under the conditions in which hypothesis testing was made part of the primary task.     

Associative priming in a masked perceptual identification task: Evidence for automatic processes

Two experiments investigated the influence of automatic and strategic processes on associative priming effects in a perceptual identification task in which prime-target pairs are briefly presented and masked. In this paradigm, priming is defined as a higher percentage of correctly identified targets for related pairs than for unrelated pairs. In Experiment 1, priming was obtained for mediated word pairs. This mediated priming effect was affected neither by the presence of direct associations nor by the presentation time of the primes, indicating that automatic priming effects play a role in perceptual identification. Experiment 2 showed that the priming effect was not affected by the proportion (.90 vs. .10) of related pairs if primes were presented briefly to prevent their identification. However, a large proportion effect was found when primes were presented for 1000 ms so that they were clearly visible. These results indicate that priming in a masked perceptual identification task is the result of automatic processes and is not affected by strategies. The present paradigm provides a valuable alternative to more commonly used tasks such as lexical decision.     

Modeling face identification processing in children and adults

Two face identification experiments were carried out to study whether and how children (5-year-olds) and adults integrate single facial features to identify faces. Using the paradigm of the Fuzzy Logical Model of Perception each experiment used the same expanded factorial design, with three levels of eyes variations crossed with three levels of mouth variations as well as their corresponding half-face conditions. In Experiment 1, an integration of facial features was observed in adults only. But, in adjusting the salience of the features varied, the results of Experiment 2 indicate that children and adults evaluated and integrated information from both features to identify a face. A weighted Fuzzy Logical Model of Perception fit the judgments significantly better than a Single Channel Model and questions previous claims of holistic face processing. Although no developmental differences in the stage of the integration of facial information were observable, differences between children and adults appeared in the information used for face identification.     

The use of visual and verbal memory processes by three-year-old children

Nonverbal (imagery) materials become more effective than verbal materials in aiding memory as age increases; indeed, children under five years have shown superior memory for verbal over nonverbal materials. The present study points out and changes four commonalities in the design of studies finding this latter relationship in an attempt to determine if nonverbal materials would prove superior to verbal ones. Four six-item paired-associate lists were presented individually using a study-test procedure. Presentation of the lists involved either pictures, words, or both. Recognition was tested either verbally or visually.Results indicated that the combined visual-verbal study materials produced performance superior to visual materials alone, which in turn were superior to verbal materials alone. Recognition of pictures was superior to recognition of words, regardless of mode of input. The relationship of these results to the procedural changes made are discussed, along with implications for current hypotheses of children's use of imagery.     

Recognition and recall by children and adults as a function of variations in memory encoding instructions

In four experiments Ss were instructed to learn a set of 40 words by producing implicit associative responses to each item (association instructions), by repeating items over and over (repetition instruction), or by using their own devices (neutral instructions). Experiment I showed that recognition memory (RM) accuracy was greatest under association instructions for adults and children and least under repetition instructions for children. The implications of these results for a frequency theory analysis for RM were discussed. Experiments II, III, and IV examined free recall (FR) as a function of encoding instructions at short (1 min) and long (either 90 min or 24 h) retention intervals. FR was worst under repetition instructions, with little overall difference between the association and neutral conditions. However, in Experiments III and IV, using school children, the neutral condition exceeded the others in FR after 90 min but not after 1 min.     

Older adults catch up to younger adults on a learning and memory task that involves collaborative social interaction

Learning and memory abilities tend to decline as people age. The current study examines the question of whether a learning situation that emphasises collaborative social interaction might help older persons overcome age-related learning and memory changes and thus perform similarly to younger persons. Younger and Older participants (n = 34 in each group) completed the Barrier Task (BT), a game-like social interaction where partners work together to develop labels for a set of abstract tangrams. Participants were also administered standard clinical neuropsychological measures of memory, on which the Older group showed expected inferiority to the Younger group. On the BT, the Older group performed less well than the Younger group early on, but as the task progressed, the performance of the Older group caught up and became statistically indistinguishable from that of the Younger group. These results can be taken to suggest that a learning milieu characterised by collaborative social interaction can attenuate some of the typical memory disadvantages associated with being older.