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In a series of experiments, participants learned to associate black-and-white shapes with nonsense spoken labels (e.g., 'joop'). When tested on their recognition memory, participants falsely recognized as correct a shape paired with a label that began with the same sounds as the shape's original label (onset-overlapping lure; e.g., joob) more often than a shape paired with a label that overlapped with the original label at offset (offset-overlapping lure; e.g., choop). Furthermore, the false-alarm rate was modulated by the phonetic distance between the sounds that distinguished the original label and the lures. Greater false-alarm rates to onset-overlapping labels were not predicted by explicit similarity ratings or by consonant identification and were not dependent upon label familiarity. The asymmetry at erroneously recognizing onset-versus offset-overlapping lures remained unchanged as the presentation of the shape at test was delayed in time, suggesting that response anticipation based on the first sounds of the spoken label did not contribute much to the false recognition of onset-overlapping lures. Thus, learning 2 words whose names differ in their last sounds appears to pose greater difficulty than learning 2 words whose names differ in their first sounds because, we argue, people are biased to give more importance to the early sounds of a name than to its last sounds when learning a novel label--referent association. Keywords: memory recognition, spoken-word recognition, temporal structure DOI: 10.1037/a0017527

Paired associates and serial list memory are typically investigated separately. An 'isolation principle' (J. B. Caplan, 2005) was proposed to explain behavior in both paradigms by using a single model, in which serial list and paired associates memory differ only in how isolated pairs of items are from interference from other studied items. In the present study, 2 experiments identify a critical dissociation between the 2 paradigms, challenging this unified account. Specifically, forward and backward probes were highly correlated for pairs and less so for short lists (triples). The authors asked whether the isolation principle could quantitatively accommodate this type of dissociation. A simulation confirmed that a single model incorporating the isolation principle can adequately explain this and other dissociations, supporting the common processes view.

This article pursues the idea of inferring aspects of phonological underlying forms directly from surface contrasts by looking at optimality theoretic linguistic systems (Prince & Smolensky, 1993/ 2004). The main result proves that linguistic systems satisfying certain conditions have the faithful contrastive feature property: Whenever 2 distinct morphemes contrast on the surface in a particular environment, at least 1 of the underlying features on which the 2 differ must be realized faithfully on the surface. A learning procedure exploiting the faithful contrastive feature property, contrast analysis, can set the underlying values of some features, even where featural minimal pairs do not exist, but is nevertheless fundamentally limited in what it can set. This work suggests that observation of surface contrasts between pairs of words can contribute to the learning of underlying forms, while still supporting the view that interaction with the phonological mapping will be necessary to fully determine underlying forms. Keywords: Linguistics; Language learnability; Phonology

Age invariance in monitoring associative learning has been the norm in numerous investigations concerning how accurately people predict future recall, predictions that are based partly on people's beliefs about forgetting. In this study, we obtained a measure of monitoring that is minimally influenced by beliefs about forgetting. Participants made quality-of-encoding (QUE) judgments by rating how well each item had been encoded. In 2 experiments, older and younger adults studied 60 paired-associate items; immediately after studying each one, they made a QUE judgment. Each item was presented at a 4-s or 8-s presentation rate. QUEs from both age groups were sensitive to the production of different strategies, presentation rate, and item characteristics. Reliable age differences in the correlation of QUEs and subsequent recall were found for related items but not for unrelated items. The outcomes indicate similar processes for generating QUE judgments by older and younger adults, but they also suggest the possibility of an age-related deficit in the accuracy of monitoring encoding in some experimental conditions.

Birdsong is considered a model of human speech development at behavioral and neural levels. Few direct tests of the proposed analogs exist, however. Here we test a mechanism of phonological development in human infants that is based on social shaping, a selective learning process first documented in songbirds. By manipulating mothers' reactions to their 8-month-old infants' vocalizations, we demonstrate that phonological features of babbling are sensitive to nonimitative social stimulation. Contingent, but not noncontingent, maternal behavior facilitates more complex and mature vocal behavior. Changes in vocalizations persist after the manipulation. The data show that human infants use social feedback, facilitating immediate transitions in vocal behavior. Social interaction creates rapid shifts to developmentally more advanced sounds. These transitions mirror the normal development of speech, supporting the predictions of the avian social shaping model. These data provide strong support for a parallel in function between vocal precursors of songbirds and infants. Because imitation is usually considered the mechanism for vocal learning in both taxa, the findings introduce social shaping as a general process underlying the development of speech and song.

Hungry pigeons received food periodically, signaled by the onset of a keylight. Key pecks aborted the feeding. Subjects responded for thousands of trials, despite the contingent nonreinforcement, with varying probability as the intertrial interval was varied. Hazard functions showed the dominant tendency to be perseveration in responding and not responding. Once perseveration was accounted for, a linear operator model of associative conditioning further improved predictions. Response rates during trials were correlated with the prior probabilities of a response. Rescaled range analyses showed that the behavioral trajectories were a kind of fractional Brownian motion.

Three experiments show that understanding of biases in probability judgment can be improved by extending the application of the associative-learning framework. In Experiment 1, the authors used M. A. Gluck and G. H. Bower's (1988a) diagnostic-learning task to replicate apparent base-rate neglect and to induce the conjunction fallacy in a later judgment phase as a by-product of the conversion bias. In Experiment 2, the authors found stronger evidence of the conversion bias with the same learning task. In Experiment 3, the authors changed the diagnostic-learning task to induce some conjunction fallacies that were not based on the conversion bias. The authors show that the conjunction fallacies obtained in Experiment 3 can be explained by adding an averaging component to M. A. Gluck and G. H. Bower's model.

The authors used paired-associate learning to investigate the hypothesis that the speed of generating an interactive image (encoding fluency) influenced 2 metacognitive judgments: judgments of learning (JOLs) and quality of encoding ratings (QUEs). Results from Experiments 1 and 2 indicated that latency of a keypress indicating successful image formation was negatively related to both JOLs and QUEs even though latency was unrelated to recall. Experiment 3 demonstrated that when concrete and abstract items were mixed in a single list, latency was related to concreteness, judgments, and recall. However, item concreteness and fluency influenced judgments independently of one another, These outcomes suggest an important role of encoding fluency in the formation of metacognitive judgments about learning and future recall.

Five experiments examined whether retrieval-induced-forgetting effects are observed for implicit tests of memory. In each experiment participants first studied category-exemplar paired associates, then practiced retrieval for a subset of items from a subset of categories before finally completing memory tests for all the studied items. In standard fashion, inhibition was measured as the performance difference of unpracticed items from practiced categories and unpracticed items from unpracticed categories. Across the 5 experiments poorer performance for unpracticed items was seen in conceptual implicit memory (category generation and category matching) but not in perceptual implicit memory (stem completion, perceptual identification). Thus retrieval-induced-forgetting effects are limited to tests of conceptual memory.

The presence of genetic variation for learning ability in animals opens the way for experiments asking how and under what ecological circumstances improved learning ability should evolve. Here we report experimental evolution of learning ability in Drosophila melanogaster. We exposed experimental populations for 51 generations to conditions that we expected to favor associative learning with regard to oviposition substrate choice. Flies that learned to associate a chemical cue (quinine) with a particular substrate, and still avoided this substrate several hours after the cue had been removed, were expected to contribute more alleles to the next generation. From about generation 15 on, the experimental populations showed marked ability to avoid oviposition substrates that several hours earlier had contained the chemical cue. The improved response to conditioning was also expressed when the flies were faced with a choice of novel media. We demonstrate that these behavioral changes are caused by the evolution of both a higher learning rate and a better memory.

Three experiments used a Pavlovian magazine-approach procedure in rats to explore, in 3 theoretically interesting cases, the inferences made from savings tests. In each experiment, a compound test procedure allowed the separation of differences in rate of acquiring new associative learning from differences in initial level of associative strength. Experiment 1 found that the slower acquisition after prior nonreinforced exposure (latent inhibition) reflected differences in learning rate, not initial level. By contrast, Experiments 2 and 3 found that the higher performance observed to a previously trained and extinguished stimulus, and lower performance observed to a conditioned inhibitor, both arose primarily because of differences in initial associative value. These experiments illustrate the usefulness of a novel testing procedure in sharpening the conclusions from savings procedures.

Five experiments used a compound test procedure to compare the rate parameters for the associative changes resulting from reinforcement and nonreinforcement. Experiments 1 and 4, using a magazine-approach procedure in rats, found initial acquisition to proceed more rapidly but to generalize less broadly than extinction. Experiments 2 and 5 repeated these observations in an autoshaping preparation with pigeons. Experiment 3 found no evidence for differential disruption of acquisition and extinction in testing. These results were obtained in a test procedure that compares responding with stimulus compounds in order to remove the differences in overall performance, which have complicated inferences about associative changes in earlier experiments.

Abstract.--Studies were conducted to assess the spatial learning ability of adults of Sceloporus poinsettii. Experimental design was such that it tested the ability (discrimination ratio, DR) of specimens to re-visit [...]

Within-compound associations play a significant role in retrospective revaluation, which in turn suggests a function for associative processes in causal learning. Modified associative theories demonstrate how this process works.

Research suggests that evaluative conditioning (EC) is most probably a form of associative learning. EC effects do not require a participant's conscious awareness, can be demonstrated in a between-subject design, and also appear in a sensory modality other than visual perception.

Five experiments examined whether past elemental or configural learning affects the coding of novel compound stimuli in human learning. Experiments 1-2B confirmed, in an unspeeded task, that past experience can have a powerful influence on whether a novel compound stimulus is treated as a combination of separate elements or as an undivided whole. Experiment 3 revealed no evidence that humans are malleable in the use of their stimulus coding strategies if the task is speeded rather than unspeeded. Experiment 4 revealed that rule abstraction as measured by a postexperimental questionnaire was not related to the occurrence of transfer. Implications for elemental and configural theories of associative learning are discussed.

Training associated pairs of perceptually dissimilar stimulus classes with a common delay or probability of food reinforcement in pigeons. Then, different choice responses were trained to 1 component class in each pair. In a choice test, the untrained class in each pair occasioned the same response as did the choice-trained class. In a 3rd experiment, 2 classes had reinforcement delays of 1 s and 15 s, respectively, and 2 other classes had reinforcement probabilities of 0.1 and 0.9. The, 1 choice response was reinforced to a class previously associated with a better condition of reinforcement (e.g., 1-s delay or 1.0 probability), and a different response was reinforced to a class previously associated with a worse condition of reinforcement (0.1 probability or 0-s delay). Testing with all classes suggested that categorization was based on the relative reinforcement or hedonic value and not on the parametric details of reinforcement.

In each of 3 experiments, rats were preexposed to the 4 distinct landmarks surrounding a circular pool before being trained to find a submerged platform located in a fixed position in the pool. When preexposure was to pairs of adjacent landmarks, it consistently retarded subsequent learning (a latent inhibition effect). When preexposure was to 1 landmark at a time, then, provided the 4 landmarks all contained a salient feature in common, preexposure facilitated subsequent learning (a perceptual learning effect). The results provide little support for the notion of a cognitive map and are quite consistent with an associative analysis.

Davey and Field in 1997 claimed that evaluative conditioning (EC) is nothing but an experimental artifact. However, researchers in this study demonstrated that what Davey and Field identify as the 'prototypical procedure' is an exception rather than the rule in EC research. They also showed that the results of their study is due to an artifact not present in any other EC study.

Three experiments used rats to examine the acquired equivalence or distinctiveness of cues occurring when 2 auditory and 2 visual stimuli were associated with either the same or with different reinforcing outcomes ([A.sub.1]+, [A.sub.2]+, [V.sub.1]*, and [V.sub.2]* vs. [A.sub.1]+, [A.sub.2]*, [V.sub.1]+, and [V.sub.2]*). Subsequent single modality discrimination learning (e.g., [A.sub.1]+, [A.sub.2]-) was assessed in Experiment 1, whereas in Experiment 2, visual and auditory discriminations were tested concurrently (i.e., {A.sub.1] +, [A.sub.2]-, [V.sub.1]-, [V.sub.2]*). In Experiment 3, auditory and visual discriminations ([A.sub.1] +, [A.sub.2]-, [V.sub.1]-, [V.sub.2]*) were trained and then reversed, using either the same ([A.sub.1]-, [A.sub.2] +, [V.sub.1]*, [V.sub.2]-) or different outcomes ([A.sub.1]-, [A.sub.2]*, [V.sub.1]+, [V.sub.2]-) within each stimulus modality. Discriminations were learned more rapidly in these studies when different outcomes were associated with stimuli from the same modality. These results challenge associative mediational theories of acquired equivalence and distinctiveness.

Two experiments examined the contributions of feature- and rule-based knowledge in a human associative learning task. Participants were presented with concurrent negative (A [right arrow] O, B [right arrow] O, AB [right arrow] no O) and positive (C [right arrow], no O, D [right arrow] no O, CD [right arrow] O) patterning problems in which certain combinations of foods were associated with an allergy outcome (O). In the test stage, some participants showed normal feature-based generalization to novel trial types, whereas other participants transferred the patterning rule (i.e., a compound and its elements signal opposite outcomes). Mastery of the discrimination presented in the training phase was strongly linked to rule-based generalization. The results suggest that models of human associative learning need to incorporate mechanisms for rule-based as well as for feature-based generalization.

In 2 experiments, rats received discrimination training in which separate presentations of A and B signaled a common pair of relationships or associations (X [right arrow] food and Y [right arrow] no food), whereas presentations of C and D signaled a different pair of relationships (X [right arrow] no food and Y [right arrow] food). To assess the nature of the associative structures acquired during this training, rats then received 2 types of revaluation procedure: In Experiment 1, A was paired with shock and C was not. In Experiment 2, the relationships that A and B had previously signaled (X [right arrow] food and Y [right arrow] no food) were paired with shock, whereas those that C and D had signaled (Y [right arrow] food and X [right arrow] no food) were not. After both types of revaluation treatment, rats showed greater generalized conditioned suppression in the presence of B than D. These results indicate that A, B, C, and D come to evoke memories of the relationships or associations that they have signaled.

Rats received exposure to two serial compounds (A-X and B-Y) comprising auditory stimuli (A and B) followed by localized visual stimuli (X and Y). A and B came to elicit responses that reflected the location of X and Y (Experiment 1). The orienting response (OR) elicited by X and Y declined during exposure to the A-X and B-Y compounds and was restored on trials when A preceded Y, and B preceded X (Experiments 2 and 3). These results, observed with use of relatively neutral stimuli, parallel those observed during Pavlovian conditioning and provide support for A. R. Wagner's (1981) account of associative learning.

It is a common assumption of associative theories of learning that no change in the strength of an associative connection between 2 cues is possible in the absence of those cues. However, recently suggested modifications to associative theory (A. Dickinson & J. Burke, 1996) have questioned this assumption by arguing that if the representations of 2 cues are simultaneously retrieved from memory, an association will be formed between them even though the cues themselves are not present. A flavor preference procedure was used to find evidence for such associations. In 3 experiments a novel excitatory connection was formed between the representations of peppermint and sucrose in their absence. This suggests that the assumption that cues cannot undergo a change of associative strength in their absence should be abandoned. The tension between the current results and accounts of mediated conditioning is discussed, and some suggestions regarding the difference between the 2 procedures are proposed.

In 4 experiments the authors used 2-stage designs to study susceptibility to interference in human discrimination learning. The experiments used a food allergy task. In Experiment 1, participants were presented with a discrimination in Stage 1 in which Food A predicted an allergy outcome (A [right arrow] O). In Stage 2, when combined with Food B, Food A predicted the absence of the allergy (B [right arrow] O, AB [right arrow] no O). In the test phase, Food A was found to have retained its Stage 1 association with the allergy despite the potentially interfering Stage 2 trials. In Experiment 2, a discrimination between 2 compounds (AB [right arrow] O, CD [right arrow] no O) remained intact despite subsequent complete revaluation of the elements, (A [right arrow] no O, B [right arrow] no O, C [right arrow] O, D [right arrow] O); in Experiments 3 and 4, a discrimination between 2 pairs of elements (A [right arrow] O, B [right arrow] O, C [right arrow] no O, D [right arrow] no O) remained intact despite subsequent complete revaluation of the AB and CD compounds, (AB [right arrow] no O, CD [right arrow] O). These experiments yielded evidence of remarkable resistance to interference in human discrimination learning. The results are at variance with the predictions of J. M. Pearce's (1987, 1994a) configural theory of associative learning.

The relevance of associative learning in the development of Obsessive-Compulsive Disorder (OCD) was investigated in a group of 23 OCD patients whose main concern was washing and 23 age and sex matched control subjects who did not have OCD. OC washers completed an origins instrument based on Menzies and Clarke's (1993, Behaviour Research and Therapy, 31, 355-365) Origins Questionnaire (OQ) for the phobic disorders. Control subjects completed a modified version of this measure designed to give a comprehensive picture of their experiences with relevant contamination-related stimuli. In general, the results question the relevance of associative-learning per se in the development of OC washing. Direct and indirect conditioning events were very rare in the OCD group, accounting for less than 13% of cases. No significant differences between groups were found in the proportion of subjects who knew other OC washers, or had experienced direct associative-learning events prior to onset. Contrary to expectation, significantly more non-OCD subjects had experienced vicarious learning events related to dirt and washing than OCD subjects. However, of note, associative-learning events that took place during episodes of depression were significantly more frequently reported in the OCD group than in the control group. Depression appeared to play a facilitating role in the associative-learning of OC washing. The implications of these findings for theoretical accounts of OCD are discussed.

The role of affective correspondence between signal and outcome in associative learning was studied in 2 experiments with 4-month-olds. In Experiment 1, an infant-directed (ID) speech segment, categorized by adults as having consoling acoustic properties for infants, was either paired or unpaired with smiling or sad face reinforcers. In other groups, a sad adult-directed (AD) speech segment signaled the smiling or sad faces. Later, all speech segments were tested for their ability to increase infants' visual interest in a checkerboard. Positive summation was observed only when the consoling ID speech segment had signaled the sad face. In Experiment 2, an arousing ID speech segment signaled the smiling or sad face. Positive summation was evident in both conditions. These results show that infants sometimes selectively associate speech segments and faces. Discussion centers on the basis for the selective association.

Evaluative conditioning experiments may be marred by a biased process of stimulus selection, resulting in apparent conditioning effects that are actually artifacts of the way the experimental stimuli are chosen. A study of conceptual conditioning elicited differential responses suggesting evaluative conditioning, but the same effects were produced in control and no treatment conditions as in the experimental condition. The present study represents the first time these control conditions were used with the evaluative conditioning paradigm.

In 4 experiments, adherence to grammatical rules and associative chunk strength (including different measures, each calculated on the basis of the frequency with which bigrams and trigrams present in the test strings appeared in the learning strings) were manipulated independently in the test phase of an artificial grammar learning task. When participants learned few items of the grammar (Experiments 1A and 2A), the associated items were more often classified as grammatical than the nonassociated ones. On the other hand, when the learning phase included most of the grammatical items (Experiments 1B and 2B), the only effect observed was an effect of grammaticality. These results suggest that, depending on the specific constraints of the tasks, knowledge based on bigrams and trigrams and knowledge based on the abstraction of the grammatical structure can be used for the classification task.

INTRODUCTION Numerous studies in animals and humans have suggested that an essential function of sleep is the strengthening of memories (e.g., Cipolli, 1995; Dujardien, Guerrien, & Leconte, 1990). The sleep-dependent [...], Recall of paired-associate lists (declarative memory) and mirror-tracing skills (procedural memory) was assessed after retention intervals defined over early and late nocturnal sleep. In addition, effects of sleep on recall were compared with those of early and late retention intervals filled with wakefulness. Twenty healthy men served as subjects. Saliva cortisol concentrations were determined before and after the retention intervals to determine pituitary-adrenal secretory activity. Sleep was determined somnopolygraphically. Sleep generally enhanced recall when compared with the effects of corresponding retention intervals of wakefulness. The benefit from sleep on recall depended on the phase of sleep and on the type of memory: Recall of paired-associate lists improved more during early sleep, and recall of mirror-tracing skills improved more during late sleep. The effects may reflect different influences of slow wave sleep (SWS) and rapid eye movement (REM) sleep since time in SWS was 5 times longer during the early than late sleep retention interval, and time in REM sleep was twice as long during late than early sleep (p < 0.005). Changes in cortisol concentrations, which independently of sleep and wakefulness were lower during early retention intervals than late ones, cannot account for the effects of sleep on memory. The experiments for the first time dissociate specific effects of early and late sleep on two principal types of memory, declarative and procedural, in humans.

INTRODUCTION It is generally believed that implicit learning and memory arc spared in patients with anterograde amnesia despite drastic impairments on standard tests of memory such as recognition and recall [...], Patients with anterograde anmesia are commonly believed to exhibit normal implicit learning. Research with the serial reaction time (SRT) task suggests that normal subjects can implicitly learn visuospatial sequences through a process that is sensitive to higher-order information that is more complex than pairwise associations between adjacent stimuli. The present research reexamined SRT learning in a group of anmesic patients with a design intended to specifically address the learning of higher-order information. Despite seemingly normal learning effects on average, the results suggest that amnesic patients do not learn higher-order information as well as control subjects. These results suggest that amnesic patients have an associative learning impairment, even when learning is implicit, and that the medial temporal lobe and/or diencephalic brain areas typically damaged in cases of amnesia normally contribute to implicit sequence learning.

Two transfer-of-control experiments assessed pigeons' sensitivity to response-outcome associations in differential-outcome discriminations. In Experiment 1, pigeons were trained on one-to-many matching-to-sample with food and no-food outcomes that were differential or nondifferential with respect to correct choice. The samples were then replaced by novel stimuli that had differential or nondifferential associations with those same outcomes. Transfer of matching occurred only when the novel samples and their respective choice responses had identical differential-outcome associations. Experiment 2 showed that the outcomes themselves were effective samples if the choices they cued yielded those outcomes in training. These data provide further evidence that the relation between comparison choice and consequent outcomes influences pigeons' matching performances.

The scientific study of associative learning began nearly 100 years ago with the pioneering studies of Thorndike and Pavlov, and it continues today as an active area of research and theory. Associative learning should be the foundation for our understanding of other forms of behavior and cognition in human and nonhuman animals. The laws of associative learning are complex, and many modern theorists posit the involvement of attention, memory, and information processing in such basic conditioning phenomena as overshadowing and blocking, and the effects of stimulus preexposure on later conditioning. An unresolved problem for learning theory is distinguishing the formation of associations from their behavioral expression. This and other problems will occupy future generations of behavioral scientists interested in the experimental investigation of associative learning. Neuroscientists and cognitive scientists will both contribute to and benefit from that effort in the next 100 years of inquiry., KEY WORDS: Pavlovian conditioning, Thorndikean conditioning, association formation, learned behavior, conditioned responding CONTENTS INTRODUCTION AND BROAD OVERVIEW What Is the Domain of Elementary Associative Learning? What Is the History of […]

Older adults show cognitive deficits in the overall speed of encoding associative information. Two studies, comparing older and younger adults on speed-related naming task performance, show that older adults have lesser episodic priming ability than younger adults. While younger adults show a flair for recalling consistently paired words, older adults show little benefit for consistently paired words. Both groups recall massed repeated words better at immediate test, but show greater recall for spaced repeated words at delayed test.

It is now clear that there are a number of different forms or aspects of learning and memory that involve different brain systems. Broadly, memory phenomena have been categorized as explicit or implicit. Thus, explicit memories for experience involve the hippocampus-medial temporal lobe system and implicit basic associative learning and memory involves the cerebellum, amygdala, and other systems. Under normal conditions, however, many of these brain-memory systems are engaged to some degree in learning situations. But each of these brain systems is learning something different about the situation. The cerebellum is necessary for classical conditioning of discrete behavioral responses (eyeblink, limb flexion) under all conditions; however, in the 'trace' procedure where a period of no stimuli intervenes between the conditioned stimulus and the unconditioned stimulus the hippocampus plays a critical role. Trace conditioning appears to provide a simple model of explicit memory where analysis of brain substrates is feasible. Analysis of the role of the cerebellum in basic delay conditioning (stimuli overlap) indicates that the memories are formed and stored in the cerebellum. The phenomenon of cerebellar long-term depression is considered as a putative mechanism of memory storage.

Two experiments with rabbits investigated the concordance of two measures of conditioning, eye-blink and potentiated startle, during a blocking sequence with paraorbital shock reinforcement. In both, a shift in the locus of shock from one eye to the other between the conditioning of an element and a compound of that element and a new cue had differential effects on the two measures of conditioning to the new cue. When the shock was unchanged, diminished conditioning in relation to controls (i.e., blocking) was observed on both measures. When the shock was changed, little conditioning was observed in startle, but control-equivalent amounts were observed in eyeblink (i.e., blocking occurred on the former but not the latter). The results are interpreted as showing a dissociation of the associative learning involving the emotive features of Pavlovian reinforcers and that involving the remaining sensory-perceptual features, and more compatible with a diminished US-processing, than with a CS-processing, view of blocking.

Pavlovian-to-instrumental transfer tests were used to assess the sensitivity of Pavlovian stimulus-outcome (S-O) associations to various extinction treatments in four appetitive conditioning experiments with rats. In Experiment 1, simple nonreinforcement of a stimulus was shown to have little impact on the ability of that stimulus to display outcome-specific transfer of control. Extinguishing a stimulus by pairing the stimulus with an alternative reinforcement in Experiment 2 also had no detectable effect on the S-O associations as assessed with the outcome-specific transfer measure. The third and fourth experiments, respectively, examined the impact of postconditioning exposures to random and explicitly unpaired S-O contingencies upon previously learned S-O associations. These treatments, as well, had no detectable harmful effects upon the integrity of the S-O associations. In contrast to the consistent failures of various extinction treatments to influence the ability of stimuli to display outcome-specific transfer, these treatments often did reduce the strength of conditioned responding initially trained to these stimuli. These results support the view that extinction entails the preservation of S-O associations as well as the parallel development of inhibitory stimulus-response associations. Other notions of extinction are also discussed.

The degree to which item and associative information can be distinguished at retrieval was assessed using a frequency-judgment task. Words were shown various numbers of times individually and as members of word pairs. At test, subjects judged the frequency of the word pairs and a word's frequency as an individual item, its frequency as a member of word pairs, or the combined frequency of the word. Subjects made all of these judgments with considerable accuracy. The frequency of presentations in the nontarget format had consistent, but small, effects on the judgments for the target frequencies. The results provide further support for the distinction between item and associative information and for the source-monitoring framework of Johnson, Hashtroudi, and Lindsay (1993), and they have important implications for global matching models of memory.

The effectiveness of infant- and adult-directed (ID and AD) speech as signals for adult faces was studied. In the pairing phase of Experiment 1, 4-month-olds received 6 presentations of an ID or AD speech segment that either preceded (forward pairings) or followed (backward pairings) the presentation of a smiling face. In the summation test phase, infants received 4 novel checkerboard pattern presentations, 2 with and 2 without the speech segment. Only infants in the ID forward pairing condition exhibited significant positive summation. In Experiment 2, the differences between ID and AD forward pairing groups were replicated with different speech exemplars. In Experiment 3, an ID speech segment that was paired with a smiling or sad face elicited significant positive summation, while one paired with a fearful or angry face did not. These differences in visual responding were not accompanied by differences in infant facial affect. Ways in which ID speech may facilitate associative learning are discussed.

Waldmann and Holyoak (1992) presented evidence in support of the claim that cue selection does not emerge in 'diagnostic' human learning tasks in which the cues are interpretable as effects and the outcomes as the causes of those effects. Waldmann and Holyoak argued that this evidence presents a major difficulty for associationist theories of learning and instead supports a 'causal model' theory. We identify a number of flaws in Waldmann and Holyoak's experimental procedures and report three new experiments designed to test their claim. In Experiment 1, cue selection was observed regardless of causal order and regardless of whether the cues were abstractly or concretely specified. In Experiments 2 and 3, cue selection was again observed when subjects predicted causes from effects. We conclude that our results are consistent with simple associationist theories of learning but contradict Waldmann and Holyoak's causal model theory.

The assumption that item and associative information are processed separately and that there is a tradeoff in the amount of each type of information that can be encoded in a given study interval (e.g., Anderson & Bower, 1972; Murdock, 1982, 1992) was examined. When item information was emphasized at study, recognition memory for associative information was poor, demonstrating that item information can be emphasized over associative information. In contrast, when associative information was emphasized, associative recognition greatly improved but item recognition did not suffer. This pattern of results was found at both fast and slow presentation rates, and for both high and low word concreteness and word frequency. Measures of confidence and response latency were also consistent with this pattern. Thus, the encoding of associative information did not measurably diminish item recognition performance.

In two experiments (ns = 3 plus a previously tested child, and 2, respectively), children learned delayed matching with complex samples, each consisting of a form and a printed nonsense word. Forms or printed words were comparison stimuli. For form comparisons, selecting the form identical to that in the preceding sample was reinforced. For printed word comparisons, selecting the word identical to that in the preceding sample was reinforced. During testing, the children then matched the forms and printed words to one another. In subsequent training, the samples were (a) old forms combined with new words or (b) old words combined with new forms. Novel matching performances among forms and words appeared across these training phases. Word-form contiguity in a matching-to-sample context may contribute to the formation of classes of stimuli that may be equivalent.

The acquisition of odor taste qualities is a result of associative learning in humans. Three experiments pairing six taste and flavor stimuli reveal that the ratings of sweetness increase postconditioning for the odors paired with sucrose and decrease for the odors paired with citric acid. Awareness of the contingencies is unnecessary for the observations of changes in the target odors. Odors presented without exposure to sucrose or citric acid show constancy in the perception of sweetness or sourness, indicating that stimulus exposure alone is an insufficient explanation.

Children's subjective judgments of speech clarity using the methods of paired comparisons and category rating were evaluated in this investigation. Eighty children with normal hearing between the ages of 4 and 8 years judged the clarity of sentences that were systematically bandpass-filtered using conditions that increased intelligibility as estimated by the Articulation Index. Subjects were classified into four age groups (4-, 5-, 6-, and 7-8-year age groups) with 20 subjects per group. With use of materials and training methods suitable for children, judgments were obtained via the two psychophysical procedures (10 subjects per age group for each procedure). Results indicated that children 5 years of age and older were able to make reliable clarity judgments using either procedure; however, the method of paired comparisons was more sensitive than category rating in detecting differences between the bandpass-filtered conditions. KEY WORDS: paired comparisons, category rating, children, hearing assessment, subjective judgments

This study investigated the effects of two associative learning tasks on aphasic subjects' labeling of novel symbols. It was designed to determine if aphasic subjects need to develop their own associations for word-symbols pairs (personalized cueing) to obtain the long-term labeling benefits observed in prior research or if comparable results are obtained when 'ready-made' associations are used during training (provided cueing). The results showed that the two cueing techniques were equal in their ability to elicit correct responses from the subjects. The results also demonstrated the long-term effectiveness of both cueing procedures on the subjects' labeling accuracy up to 30 days after training was discontinued. KEY WORDS: aphasia, associative learning, verbal labeling, brain damaged, adulthood