Automatic activation of episodic information in a semantic memory task.

Conducted 4 experiments with 122 undergraduates to examine priming between newly learned associates and priming between well-known associates in lexical decision. All experiments showed that priming occurred between newly learned associates, including conditions in which the stimulus onset asynchrony (SOA) between prime and target was short (150 msec) and in which the probability was low (1/12) that the prime and target of a pair would be associated to each other. It is concluded, contrary to suggestions by M. Carroll and K. Kirsner (see record 1982-25008-001) and E. Tulving (1983), that newly learned associates can prime each and that they can do so at short SOAs. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Retrieval blocks in episodic and semantic memory.

A retrieval block (RB) refers to impaired accessibility in retrieving target information when semantically related information is presented or retrieved prior to target retrieval. A research review reveals that RBs occur in a variety of situations, including both episodic and semantic memory tasks. RBs have been most thoroughly studied in the part-list cuing paradigm in episodic recall, but similar principles seem to operate in other situations, including the A–B, A–D interference paradigm, episodic recognition, and the tip-of-the-tongue situation. Evidence for such RBs is problematic for theories postulating automatic spreading activation among associated nodes in memory. Difficulties with theories that account for such RBs are discussed. Further research on RBs may help illuminate similar phenomena, such as the effects of Einstellung in thinking and problem solving. (French abstract) (76 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamics of activation in semantic and episodic memory.

Two experiments with the adaptive priming procedure are reported to test discrete and continuous activation models for the structure of semantic and episodic memory. In Experiment 1, the prime and test stimuli were semantically associated words (e.g., bread–butter). In Experiment 2, episodic associations between the prime and test stimuli were established through paired associate learning. For both cases, the mixture prediction failed, and 2-state activation models were rejected. We conclude that models with only 2 discrete states of activation, that is, all-or-none models, do not accurately characterize the dynamics of activation in semantic and episodic memory. Higher order discrete or continuous models may better account for the results. Our findings are consistent with several current continuous models of spreading activation. They contrast, however, with those from previous work in which response-preparation processes appeared to proceed in a discrete, all-or-none fashion (Meyer, Yantis, Osman, & Smith, 1985). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult age differences in semantic and episodic memory

Cleft lip and palate occurs in approximately 1 in every 750 live human births, making it one of the most common congenital malformations. Surgical closure of the palatal cleft does not always result in a velopharyngeal port capable of supporting normal speech. The University of Florida (UF), in collaboration with the University of S?o Paulo (USP), is engaging in a 5-year prospective, randomized controlled study to compare velopharyngeal function for speech outcomes between patients undergoing palatoplasty for complete unilateral cleft lip and palate performed using the von Langenbeck procedure with intravelar velarplasty and those receiving the Furlow double-reversing Z-plasty palatoplasty. The von Langenbeck procedure was selected as the time-tested standard against which the Furlow procedure could be judged. The Furlow procedure, a relatively new operation, has been reported to yield substantially higher rates of velopharyngeal competency for speech than have most other reported series and theoretically should result in less disturbance to midfacial growth. A total of 608 patients will be entered into one of two age categories. Inclusion of two age groups will allow a comparison of results between patients having surgery before 1 year of age (9-12 months) and patients undergoing surgery at approximately 1.5 years of age (15-18 months). Speech data will be collected and will be available for definitive analysis throughout the last 3 years of the study. Collection of preliminary growth data will require more than 5 years; growth analysis is anticipated to continue until all patients have reached maturity. The Hospital for Research and Rehabilitation of Patients with Cleft Lip and Palate at the University of S?o Paulo (USP-HPRLLP) in Bauru, Brazil, is uniquely situated for conducting this study. The well-equipped and modern facilities are staffed by well-trained specialists representing all disciplines in cleft-palate management. In addition, an already existing social services network throughout Brazil will ensure excellent follow-up of study cases. The clinical caseload at this institution currently exceeds 22,000, and more than 1200 new cases are added annually. This project represents a unique opportunity to obtain prospective data from a large number of subjects while controlling the variables that have traditionally plagued cleft-palate studies. This study is designed to determine which of the two proposed surgical procedures is superior in constructing a velum capable of affecting velopharyngeal competency for the development of normal speech.     

Semantic knowledge and episodic memory for faces in semantic dementia.

Previous studies have documented poor recognition memory for faces in patients with semantic dementia. Preserved face recognition memory was found in this study, however, so long as atrophy was confined predominantly to the left temporal lobe. Patients with structural damage to the right temporal lobe were typically impaired, with the status of the hippocampus and parahippocampal gyrus (including the perirhinal cortex) on the right being critical. Two single-case studies of patients with predominantly left temporal lobe pathology confirmed good recognition memory for famous faces, even if semantic knowledge about the celebrities depicted was severely degraded. An effect of semantic knowledge on recognition memory became apparent only when perceptually different photographs of the famous people were used at study and test. These results support the view that new episodic learning typically draws on information from both perceptual and semantic systems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neural correlates of semantic and episodic memory retrieval

To investigate the functional neuroanatomy associated with retrieving semantic and episodic memories, we measured changes in regional cerebral blood flow (rCBF) with positron emission tomography (PET) while subjects generated single word responses to achromatic line drawings of objects. During separate scans, subjects either named each object, retrieved a commonly associated color of each object (semantic condition), or recalled a previously studied uncommon color of each object (episodic condition). Subjects were also scanned while staring at visual noise patterns to provide a low level perceptual baseline. Relative to the low level baseline, all three conditions revealed bilateral activations of posterior regions of the temporal lobes, cerebellum, and left lateralized activations in frontal regions. Retrieving semantic information, as compared to object naming, activated left inferior temporal, left superior parietal, and left frontal cortices. In addition, small regions of right frontal cortex were activated. Retrieving episodic information, as compared to object naming, activated bilateral medial parietal cortex, bilateral retrosplenial cortex, right frontal cortex, thalamus, and cerebellum. Direct comparison of the semantic and episodic conditions revealed bilateral activation in temporal and frontal lobes in the semantic task (left greater than right), and activation in medial parietal cortex, retrosplenial cortex, thalamus, and cerebellum (but not right frontal regions) in the episodic task. These results support the assertion that distinct neural structures mediate semantic and episodic memory retrieval. However, they also raise questions regarding the specific roles of left temporal and right frontal cortices during episodic memory retrieval, in particular.     

The episodic–semantic memory distinction and paired associate learning.

39 senile dementia patients (mean age 69.1 yrs) completed the Associate Learning subtest of the Wechsler Memory Scale, and orthogonal measures of episodic and semantic memory were developed through factor analysis. As predicted, scores on the semantic factor were related only to learning high-associate word pairs; scores on the episodic factor were related to both high- and low-associate learning. Findings provide an interpretive framework for the Associate Learning subtest and support E. Tulving's (1972) 2-store model of long-term memory. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and autobiographical memory: Dissociating episodic from semantic retrieval.

Cognitive aging research documents reduced access to contextually specific episodic details in older adults, whereas access to semantic or other nonepisodic information is preserved or facilitated. The present study extended this finding to autobiographical memory by using a new measure: the Autobiographical Interview. Younger and older adults recalled events from 5 life periods. Protocols were scored according to a reliable system for categorizing episodic and nonepisodic information. Whereas younger adults were biased toward episodic details reflecting happenings, locations, perceptions, and thoughts, older adults favored semantic details not connected to a particular time and place. This pattern persisted after additional structured probing for contextual details. The Autobiographical Interview is a useful instrument for quantifying episodic and semantic contributions to personal remote memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Searching memory for physical and semantic information.

Three experiments, each with 12 paid undergraduates, determined whether scanning active memory for 2 types of information in parallel depends on the existence of different memory codes. Ss searched short lists of items for 2 types of semantic information, 2 types of physical information, or information of both types. It was found that both searches were conducted in parallel no matter what the nature of the information retrieved. Such parallel processing constitutes one strategy for improving the efficiency of searching active memory. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A diffusion model analysis of adult age differences in episodic and semantic long-term memory retrieval.

Two experiments investigated adult age differences in episodic and semantic long-term memory tasks, as a test of the hypothesis of specific age-related decline in context memory. Older adults were slower and exhibited lower episodic accuracy than younger adults. Fits of the diffusion model (R. Ratcliff, 1978) revealed age-related increases in nondecisional reaction time for both episodic and semantic retrieval. In Experiment 2, an age difference in boundary separation also indicated an age-related increase in conservative criterion setting. For episodic old-new recognition (Experiment 1) and source memory (Experiment 2), there was an age-related decrease in the quality of decision-driving information (drift rate). As predicted by the context-memory deficit hypothesis, there was no corresponding age-related decline in semantic drift rate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental differences in episodic retrieval: The role of differences in concept representations in semantic memory.

Developmental differences in the relative salience of features in concept representations in semantic memory and their contributions to differences in cued recall were examined in two experiments. For second graders, fifth graders, and college students, acquisition encoding of cue–target noun pair information was constrained by means of defining-, characteristic-, category-, and incidental-feature orienting questions. At retrieval, the encoding of cue information alone was constrained (Experiment 1) within subjects by means of the same (e.g., defining at acquisition and defining at retrieval) or related (e.g., defining at acquisition and characteristic at retrieval) retrieval questions or was unconstrained (Experiment 2). In both experiments, the acquisition presentation duration was manipulated (1 s or 5 s) in order to examine the spread of feature activation within concepts. The results showed that recall varied with feature salience, with the salience greatest for defining features. In addition, the results suggested that the relative salience of defining features was at least as great for the children as for the adults. The results offer no support for Keil and Batterman's (1984) hypothesis of a shift from characteristic to defining features in the development of word meaning representation in memory. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Retrieval-induced forgetting in episodic memory.

Participants learned the locations of 12 stimuli that were uniquely colored but could be grouped by shape (4 circles, 4 triangles, 4 crosses). Following the study, a retrieval-practice phase required participants to recall the colors of a subset of the stimuli (i.e., 2 circles, 2 triangles) using shape and location as cues. In a final test, participants recalled the colors of all 12 stimuli. Compared with the control set of stimuli (i.e., 4 crosses), memory was facilitated for practiced items but impaired for related items, which were not practiced but shared the same shape group. Across experiments, retrieval-induced forgetting was observed for different perceptual groupings and for different cuing procedures. The effect, however, required retrieval of information during the interpolated phase. Providing extra presentations did not disrupt memory for related items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recognition processes in episodic memory.

In 5 series of experiments with 5th, 6th, and 10th graders and undergraduate and university students, Ss encouraged to process related sentences at the same time (integrated storage) were compared with those encouraged to process the related sentences independently of each other (independent storage). Overall results show that Ss in the integrated storage condition were better at deriving inferences based on interconnections among the related items, at identifying the sentences that had been presented, and at recalling the sentences to a word cue. There was no difference between conditions on word recognition tests. Thus, Ss in the independent condition had a more difficult time retrieving the sentences that had been presented, but not in identifying the words contained in these sentences. This finding is explained by postulating a 2-stage recognition process. It was also found that Ss were able to combine 2 related sentences presented independently of each other, if the intervening sentences did not contain concepts in common with these sentences. However, when there were several sentences containing overlapping information, each presented independently of the others, Ss were unable to combine them into a single idea. This result indicates that the presence of several episodic traces containing common concepts interferes with the retrieval of information from these traces. (French summary) (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rated associability and episodic memory.

There is some conflict in the literature over the question of whether paired-associate episodic memory improves systematically with the "associability" of the word pairs in question. In the present 3 studies with summer school students, associability was measured by ratings. Results show that under certain circumstances, episodic memory performance was affected by ceiling effects such that a simple relationship between episodic memory for paired associates and the rated associability of the pairs was difficult to demonstrate. However, when ceiling effects were avoided, either by having Ss study a great many pairs at once or by using unusually long lists, episodic memory was monotonically related to rated associability. It is suggested that word frequency should also be considered along with rated associability in this context. (French abstract) (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The influence of apoe status on episodic and semantic memory: Data from a population-based study.

In a prospective cohort study, the authors demonstrated a more pronounced ε4-related deficit for participants 70 years of age and older in tasks assessing episodic recall. Apolipoprotein E (APOE) and age interacted for episodic memory tasks, whereas the interaction for semantic memory tasks was between APOE and test wave. Heterozygotes of ε4 between middle-age and young-old participants performed at a higher level than noncarriers of this allele in recall tasks. A dose effect was found such that carriers of 2 ε4 alleles failed more profoundly in acquiring and recollecting episodic information than carriers of 1 ε4 allele, who in turn failed more than carriers of non-ε4 alleles. The pattern of findings observed for older ε4 carriers suggests that these individuals have particular difficulty when the executive task demands are high. Several factors (e.g., smaller hippocampal volumes, less effective neural repair mechanisms) may account for these findings. On the basis of the data obtained, the authors argue that analyses of the effect of specific genes in cognition should be accompanied by assessment of performance at a specific level, with due attention to the individual's age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

What kind of a hypothesis is the distinction between episodic and semantic memory?

Responds to comments by G. McKoon et al (see record 1986-19143-001) regarding the present author's (1983; also see record 1985-03110-001) claims of a distinction between semantic and episodic memory by asserting that the hypothetico-deductive method of testing theories advocated by McKoon et al is not an appropriate procedure for evaluating the validity of classification according to learning and memory phenomena and processes. (73 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Process complexity in semantic memory.

Are sentences verified by a lone computational mechanism, or does this mechanism race in parallel with a generally faster search of semantic memory? Rejecting either the single- or dual-process account would clarify whether semantic memory is structured or is a relatively unstructured (computational) system. This study examined verification reaction time (RT) distributions for a dissociation between fast and slow RTs due to the manipulation of semantic variables. A race between a search and a generally slower computational process should yield an RT distribution whose fastest RTs are usually determined by the search and whose slowest RTs are usually determined by computation. If a manipulation affects these 2 processes differently, the fast and slow RTs will be differentially affected. Results from 3 verification experiments support this view. Other results suggest even greater process complexity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

More on the distinction between episodic and semantic memories.

Responds to E. Tulving's (see record 1986-19162-001) reply to the critique of the present authors and a colleague (see record 1986-19143-001) regarding episodic/semantic distinction of memory by asserting that the classification methods proposed by Tulving may be detrimental to the advancement of theory and that whole domains of inquiry should not be excluded from the usual criteria of experimental psychology. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult aging effects on semantic and episodic priming in word recognition.

Two experiments compared automatic semantic and episodic priming effects in adult aging. In the 1st experiment, target words were semantically primed; in the 2nd experiment, targets were primed by repetition of semantically unrelated words. Both experiments involved a pronunciation task with response signals at fixed times following target onset. Consequently, priming was measured as improvement in the percentage of correct responses. Priming was also calculated with speed–accuracy measures of intercept and slope. Both types of priming effect were significant in the percentage correct and slope measures, but no age group differences were found. Furthermore, the magnitudes of the priming effects were equivalent. The age-resistant nature of semantic and episodic priming, as well as evidence for a common theoretical mechanism, is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object naming and semantic knowledge in temporal lobe epilepsy.

Object-naming impairment is common among temporal lobe epilepsy (TLE) patients, but other aspects of semantic memory have received limited attention in this population. This study examined object-naming ability and depth of semantic knowledge in healthy controls (n?=?29) and patients with early onset TLE (n?=?21). After administration of the Boston Naming Test (BNT), the authors asked participants to provide detailed definitions of 6 BNT objects. The TLE group demonstrated a significant deficit relative to controls in both object-naming ability and semantic knowledge for the target objects, even after controlling for IQ. In a multiple regression analysis that included other neuropsychological test scores as independent variables, the semantic knowledge score was the only significant predictor of patients' object-naming performance. Thus, at the group level, early onset TLE patients have a semantic knowledge deficit that contributes to dysnomia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)