Recognition vs recall of visually vs acoustically confusable letter matrices

In an attempt to separate auditory and visual components in short-term memory, five subjects were exposed to letter matrices composed of six visually confusable letters, six acoustically confusable letters, or a mixture of the two, under two response conditions: recognition and recall. A 50-msec stimulus presentation was followed by a variable dark interval of 1, 250, 1,000, or 3,000 msec. In the recall condition, the interval was followed by a buzzer which signaled the subject to recall, in any order, as many letters as possible. In the recognition condition, the variable interval was followed by a second letter matrix which was either identical to the first matrix or differed from is by one letter. Subjects responded either "same" or "different." The results support the notion that the auditory component plays a major role in recall, whereas the visual component dominates in recognition.     

Effects of Item Difficulty on the Retrieval of Solutions during Cognitive Skill Acquisition: Age Differences

ABSTRACT

In cognitive skill learning, shifts to better strategies for obtaining solutions often occur while associations between problems and solutions are being strengthened. In two skill learning experiments, we examined the effects of item difficulty on the retrieval of solutions and the learning of problem–solution associations in younger and older adults. The results of both experiments demonstrated an ‘easy effect’ in both younger and older adults, such that the retrieval of solutions as well recognition memory for problems was best for the easier items. In addition, a ‘hard effect’ was found in younger adults, but not in older adults, whereby the retrieval of solutions as well as recognition memory for problems was better for harder items than for medium-difficulty items. The finding that increased computational demands at the item level delayed item memorization and the retrieval of solutions in older adults but not younger adults is consistent with a general-resources account of age-related differences in skill learning.     

Cognitive skill learning: age-related differences in strategy shifts and speed of component operations

Younger and older adults solved novel arithmetic problems and reported the strategies used for obtaining solutions. Age deficits were demonstrated in the latencies for computing and retrieving solutions and in the shift from computation to retrieval. Rates of improvement within age groups were parallel for computations and retrievals, suggesting a single, age-attenuated mechanism that affects practice-related speedup. The age-related delay in strategy shift suggests either reluctance to use retrieval or an associative memory deficit. Experiment 1 showed that skill acquisition was unaffected by the presence and frequency of postresponse strategy probes for both age groups. Experiment 2 showed that pretraining item-learning operations facilitated subsequent item learning and that pretraining either item-learning operations or the algorithm did not alter the age trends.     

Effects of item difficulty on the retrieval of solutions during cognitive skill acquisition: age differences

In cognitive skill learning, shifts to better strategies for obtaining solutions often occur while associations between problems and solutions are being strengthened. In two skill learning experiments, we examined the effects of item difficulty on the retrieval of solutions and the learning of problem-solution associations in younger and older adults. The results of both experiments demonstrated an 'easy effect' in both younger and older adults, such that the retrieval of solutions as well recognition memory for problems was best for the easier items. In addition, a 'hard effect' was found in younger adults, but not in older adults, whereby the retrieval of solutions as well as recognition memory for problems was better for harder items than for medium-difficulty items. The finding that increased computational demands at the item level delayed item memorization and the retrieval of solutions in older adults but not younger adults is consistent with a general-resources account of age-related differences in skill learning.     

A prelearning manipulation falsifies a pure associational deficit account of retrieval shift during skill acquisition

Older adults adopt memory-based response strategies during consistent practice more slowly and less completely than younger adults. In two experiments, participants either prelearned all, half, or none of the noun-pair stimuli prior to the completion of a standard noun-pair lookup task. Higher proportions of prelearning generally led to a faster and more complete strategic shift from visual scanning to memory retrieval during the lookup task, and a strong prelearning criterion for all items eliminated the age-related slowing of retrieval shift. However, the 50% prelearned condition resulted in strategy shift that was inconsistent with simple mechanistic associative learning, revealing a strategic set that was retrieval-avoidant in older adults.     

A prelearning manipulation falsifies a pure associational deficit account of retrieval shift during skill acquisition

ABSTRACT

Older adults adopt memory-based response strategies during consistent practice more slowly and less completely than younger adults. In two experiments, participants either prelearned all, half, or none of the noun-pair stimuli prior to the completion of a standard noun-pair lookup task. Higher proportions of prelearning generally led to a faster and more complete strategic shift from visual scanning to memory retrieval during the lookup task, and a strong prelearning criterion for all items eliminated the age-related slowing of retrieval shift. However, the 50% prelearned condition resulted in strategy shift that was inconsistent with simple mechanistic associative learning, revealing a strategic set that was retrieval-avoidant in older adults.     

Item learning in cognitive skill training: Effects of item difficulty

Item difficulty effects in skill learning were examined by giving participants extensive training with repeated alphabet arithmetic problems that varied in addend size (e.g., C ? D = ? is easy; C ? J = ? is harder). Recognition memory for the items, as measured by interpolated recognition tests, was acquired early in training and was unaffected by item difficulty. Memory for the solutions to items, as measured by the participants’ strategy reports that they had retrieved, rather than computed, the solution, was acquired later and was affected by item difficulty. Solutions to easier items were learned earlier in training for both young adults (18–24 years) and older adults (60–75 years), superimposed on an overall lower level of solution learning in older participants. The results suggest that the formation of associations between problems and their solutions is effortful and shares limited processing resources with the computational demands of the problem.     

Effects of response time deadlines on adults' strategy choices for simple addition

In this investigation of adults' solution strategies for simple arithmetic, participants solved addition problems (e.g., 2 + 3, 8 + 7) under fast and slow response deadlines: The participants were instructed either to respond before a 750-msec warning beep, or to wait for a 2,500-msec beep before responding. After each trial, they indicated whether they had solved the problem by direct memory retrieval or by using a procedural strategy (e.g., counting, transformation). It was predicted that the fast deadline condition should curtail the use of procedural strategies, which generally are slower than direct retrieval. Furthermore, this deadline effect should be exaggerated for numerically larger problems because procedural strategies are especially slow for the larger problems. As predicted, we observed a deadline x size interaction whereby the fast deadline increased reported use of retrieval, especially for large problems. The results confirm that reported use of direct retrieval decreases systematically with elapsed time, and they provide additional evidence that young, educated adults rely substantially on procedural strategies even for simple addition.     

Selective perception without confounding contributions of decision and memory

Previous research has demonstrated that decision processes and short-term memory limitations contribute to the observed limitation in the span of apprehension in tachistoscopic experiments. The present study addresses the question of whether perceptual factors also contribute to this limitation. Observers were asked to indicate which of four target letters occurred in a four-item test display. The irrelevant background items were either highly confusable or completely nonconfusable with the target letters. The target detection task is designed to bypass short-term memory limitations. In order to eliminate differences in decision processing, the location of the target letter was indicated either slightly before or shortly after the display presentation. The indicator was either an arrow cue or a pattern mask. Performance decreased with increases in the delay of the arrow cue only when the background items were confusable. The pattern mask yielded standard masking functions, but performance with the nonconfusable background items improved more rapidly with increases in processing time than did performance with the confusable background items. These results conform to the hypothesis that attention operates at the perceptual stage of processing. The results were accurately described by a quantification of attentional effects in a general information processing model.     

Strategy shift affordance and strategy choice in young and older adults

When skill acquisition involves a shift in strategy (such as from rule-based to retrieval-based processing), older adults typically shift later in practice than young adults do. We observed the shift from scanning-based to memory-based processing in a noun pair learning task. Young and older adults were trained in conditions in which the relationship between memory load and scanning load was manipulated by making the strategy shift more or less beneficial. Older adults in a condition with high shift affordance shifted to memory retrieval more fully and more rapidly than did older adults in conditions with lower shift affordance. Reluctance to rely on memory retrieval was related to metacognitive reports of memory confidence. The present study indicates that age differences in skill acquisition reflect qualitative age differences in strategy choice in addition to quantitative age differences in component task processes.     

Situating math word problems: The story matters

In two experiments, we explored how the situation model of a math story problem impacts math problem performance. Participants completed multiplication story problems in which a set of objects was associated with or dissociated from a protagonist, making them more or less accessible in memory during answer retrieval. On the basis of previous findings that the sum of two numbers interferes with retrieval of their product, the number of objects in the math problem was either highly interfering (“9” for 4 3 5) or less interfering (“8” for 4 3 5) for multiplication retrieval in the problem. Participants made more errors in problem solving when highly interfering numerical content was associated with the protagonist and, thus, foregrounded. Moreover, the lower one’s working memory, the bigger this effect. In sum, small changes in the situation model of a math story problem can harm performance. These changes shift the balance of factors that influence math performance away from math knowledge and toward individual differences in general cognitive capacity.     

Shock as a signal for shock or no-shock: a feature-negative effect in conditioned suppression.

Rats were trained in conditioned suppression discriminations where shock at the beginning of a trial signaled either shock or no-shock at the end of the trial. In the shock-positive condition, shock at the beginning of a presentation of white noise signaled that noise would end with shock; noise that did not begin with shock did not end with shock. In the shock-negative discrimination, shock at the beginning of noise signaled that noise would not end with shock; presentations of noise that did not begin with shock ended with shock. In shock-random training, shock at the beginning of noise did not reliably signal whether the noise presentation would or would not end with shock. Most subjects in shock-negative training quickly developed a differential pattern of suppression on positive (shock reinforced) trials and no suppression on negative (nonreinforced) trials. The shock-positive discrimination was much more difficult to establish and was not acquired by the majority of the rats. This "feature-negative" effect is a clear exception to the general superiority of feature-positive learning commonly observed in discriminations based on a single distinguishing feature. The results are discussed in terms of Pavlovian stimulus-shock contingencies in the shock-positive and shock-negative paradigms, which appear to favor rapid development of the shock-negative discrimination.     

Reversal and nonreversal shifts in autistic children

Reversal and nonreversal shifts in nineteen 2- to 14-year-old autistic children were studied. Each child was taught both a reversal and nonreversal shift discrimination task. The reversal shift condition entailed teaching the child to respond to one (the S+) of a pair of stimuli during training and subsequently reversing the S+ during testing. The nonreversal shift condition consisted of teaching the child two unrelated discriminations during training and testing. The results indicated that the older autistic children did better on reversal shifts than younger children who did better on nonreversal shifts. These findings are consistent with those for normal children.     

Solving problems by analogy: The benefits and detriments of hints and depressed moods

In Experiment 1, mildly depressed (dysphoric) and nondysphoric subjects tried to solve logic problems that were analogous to subsequent target problems; then they attempted target solutions with or without hints in the form of the anologues’ themes. Target solutions were impaired by the hints in the nondysphoric group alone. Experiment 2A was a no-training control to verify that transfer did indeed occur. In Experiment 2B, all subjects received hints in the transfer phase; the training phase was either problem oriented (as in Experiment 1) or memory oriented. Again, nondysphoric subjects solved fewer problems following problem-oriented training than did both dysphoric subjects in that condition and nondysphoric subjects with memory-oriented training. Experiment 3 replicated the previous results in the nondysphoric samples. We interpret these findings within the transferappropriate processing framework.     

Emergence of Information-Retrieval Strategies in Numerical Cognition: A Developmental Study

A series of simple addition problems was presented in a reaction time, true-false verification task to subjects in Grades 2 through 4 and in college. This information-processing paradigm was used to measure the solution strategies used for problems that sometimes are solved too rapidly and accurately to allow for meaningful error analysis. A series of structural models representing different processing sequences was tested against reaction times for solution to different two-term addition problems. Young children and adults alike used a memory access process to solve highly overlearned addition problems such as 1 + 1 = 2, but solution strategies of more difficult problems differed by age. Younger children adopted a slow, effortful, implicit counting strategy, with efficiency developing in the middle elementary school years; adults performed in a manner consistent with at least some models of memory retrieval found in the literature. Children were classified into two groups, independently of grade, based on slope values from a regression equation computed on individual subject data. The two groups comprised what appeared to be "fast" and "slow" processors, who differed in terms of speed of processing as well as strategy used. Our findings are discussed in terms of models of semantic memory and the development of automatic information-processing skills.     

Problem solving by reference to rules or previous episodes: The effects of organized training,analogical models,and subsequent complexity of experience

Subjects learned a microcomputer drawing package under different conditions of training organization and practice complexity. Training instructions were presented in either a random or an organized order, and with or without an analogical model of the software package. Practice trials varied in visual and logical complexity. Performance on paper-arid-pencil and problem-solving tests was better following the model than following the no-model condition when practice trials were logically complex; the reverse was true when they were logically simple. Performance on the test of problem solving was also better following organized training than following randomly ordered training when practice trials were visually complex; the reverse was true following visually simple practice. We propose that the subjects performed the tasks by engaging in either episodebased or rule-based processing, and that performance was optimized when the processing used at encoding and retrieval was the same. The acquisition of skill in solving real problems is explained as procedural compilation.     

Dynamic shifts of pigeon local/global attention

It has previously been shown that pigeons can shift attention between parts and wholes of complex stimuli composed of larger, "global" characters constructed from smaller, "local" characters. The base-rate procedure used biased target level within any condition at either the local or global level; targets were more likely at one level than at the other. Biasing of target level in this manner demonstrated shifts of local/global attention over a time span consisting of several days with a fixed base rate. Experiment 1 examined the possibility that pigeons can shift attention between local and global levels of perceptual analysis in seconds rather than days. The experiment used priming cues the color of which predicted on a trial-by-trial basis targets at different perceptual levels. The results confirmed that pigeons, like humans, can display highly dynamic stimulus-driven shifts of local/global attention. Experiment 2 changed spatial relations between features of priming cues and features of targets within a task otherwise similar to that used in experiment 1. It was predicted that this change in cues might affect asymmetry but not the occurrence of a priming effect. A priming effect was again obtained, thereby providing generality to the claim that pigeons can learn that trial-by-trial primes predict targets at different levels of perceptual analysis. Pigeons can display perceptual, stimulus-driven priming of a highly dynamic nature. Electronic Publication     

Cognitive skill acquisition and transfer in younger and older adults.

The acquisition of cognitive skills often depends on 1 of (or a combination of) 2 processes, the execution of an algorithm, and the retrieval of problem instances. This study examined the effects of age and repetition of problem instances on the production and verification of solutions to 2 serially presented sets of alphabet arithmetic problems. Analyses of the parameters derived from power-function fits for individuals revealed age differences favoring young adults in improvement span, learning rate, and asymptote. For both age groups, the beneficial effects of repetitions on 1st-set response times were attributable to algorithmic speedup and to the retrieval of instances, whereas improvements in the speed of 2nd-set response times were attributable primarily to item retrieval.     

Are item-level strategy shifts abrupt and collective? Age differences in cognitive skill acquisition

Item-level analysis allows for the examination of qualitative age and individual differences in skill acquisition, which are obscured when aggregating data across items. In the present study, item-level strategy shifts were generally gradual and variable, rather than abrupt and collective. Strategy shift reversions were frequent, and the total transition space was extensive, for both younger and older adults. Shift indices were highly variable between items for both younger and older adults. Age differences in item-level shift patterns suggest that older adults’ greater conservatism in strategy selection leads to more gradual strategy shift transitions for individual items as well as to more collective strategy shifts.     

Improving specific autobiographical memory in older adults: impacts on mood,social problem solving,and functional limitations

Older adults have difficulty recalling specific autobiographical events. This over-general memory style is a vulnerability factor for depression. Two groups receiving interventions that have previously been successful at reducing over-general memory in depressed populations were compared to a control group. Participants were healthy older adults aged ≥70 years: memory specificity training (MEST; n = 22), life review (n = 22), and control group (n = 22). There were significant improvements in autobiographical memory specificity in the MEST and life review groups at post-training, relative to the control group, suggesting that over-general memory can be reduced in older adults. Change in social problem solving ability and functional limitations were related to change in autobiographical memory specificity, supporting the suggested role of specific retrieval in generating solutions to social problems and maintaining independence. Qualitative analysis of participants’ feedback revealed that life review may be more appropriate for older adults, possibly because it involves integrating specific memories into a positive narrative.