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Douglas L Nelson

Publications and source records attributed to Douglas L Nelson.

9 recordsLinked to original sources
PubMed2006

Recursive reminding: effects of repetition, printed frequency, connectivity, and set size on recognition and judgments of frequency.

In the present experiments, predictions of common path and recursive-reminding models of recognition (RG) and judgments of frequency (JOFs) were contrasted. The results indicated that each task is affected by study frequency, printed frequency, and associative connectivity. However, effect size analyses indicated that study frequency and item attributes show a double dissociation over tasks. Study frequency has a greater effect on JOFs than on RG, whereas printed frequency and associative connectivity have greater effects on RG than on JOFs. The recursive-reminding model predicts differential effects of study frequency, because it assumes that although both tasks are influenced by familiarity, JOF is more likely to be affected by recollective reminding as a procedure for encoding event frequency. Associative set size effects were absent in each task, suggesting that competitors play no role in either task.

Association Learning↗
PubMed2005

What is preexisting strength? Predicting free association probabilities, similarity ratings, and cued recall probabilities.

Measuring lexical knowledge poses a challenge to the study of the influence of preexisting knowledge on the retrieval of new memories. Many tasks focus on word pairs, but words are embedded in associative networks, so how should preexisting pair strength be measured? It has been measured by free association, similarity ratings, and co-occurrence statistics. Researchers interpret free association response probabilities as unbiased estimates of forward cue-to-target strength. In Study 1, analyses of large free association and extralist cued recall databases indicate that this interpretation is incorrect. Competitor and backward strengths bias free association probabilities, and as with other recall tasks, preexisting strength is described by a ratio rule. In Study 2, associative similarity ratings are predicted by forward and backward, but not by competitor, strength. Preexisting strength is not a unitary construct, because its measurement varies with method. Furthermore, free association probabilities predict extralist cued recall better than do ratings and co-occurrence statistics. The measure that most closely matches the criterion task may provide the best estimate of the identity of preexisting strength.

Comprehension↗
PubMed2004

The University of South Florida free association, rhyme, and word fragment norms.

Preexisting word knowledge is accessed in many cognitive tasks, and this article offers a means for indexing this knowledge so that it can be manipulated or controlled. We offer free association data for 72,000 word pairs, along with over a million entries of related data, such as forward and backward strength, number of competing associates, and printed frequency. A separate file contains the 5,019 normed words, their statistics, and thousands of independently normed rhyme, stem, and fragment cues. Other files provide n x n associative networks for more than 4,000 words and a list of idiosyncratic responses for each normed word. The database will be useful for investigators interested in cuing, priming, recognition, network theory, linguistics, and implicit testing applications. They also will be useful for evaluating the predictive value of free association probabilities as compared with other measures, such as similarity ratings and co-occurrence norms. Of several procedures for measuring preexisting strength between two words, the best remains to be determined. The norms may be downloaded from www.psychonomic.org/archive/.

Free Association↗
PubMed2004

Strengthening the activation of unconsciously activated memories.

Reading a word activates a set of associated words-for example, reading CAB activates car, driver, and other associates. This research was conducted to determine whether the unconscious activation of these associates adds activation to other associates in the same set. Words were studied, and recall was tested with cues comprised of associates directly activated by the target. On the basis of preexisting links, the associates serving as test cues also received strong (e.g., car) or weak (e.g., driver) additional inputs from other associates in the set. Cues receiving stronger inputs from other associates were more effective, indicating that unconsciously activated associates strengthen one another. This effect declined when conditions disrupted the retrieval of context features linked to the episode. Attending to another task during or after study or receiving implicit test instructions decreased the effects of input from other associates. Importantly, disruptions affected input from other associates more than direct input from the target, suggesting that the influence of context wanes as the links in the network become more distant.

Association↗
PubMed2003

Disrupting attention: the need for retrieval cues in working memory theories.

Sometimes in conversation, something is said that causes us to want to comment, but before our impending but implicit thoughts can be expressed, the conversation is disrupted. Later, we cannot recall what we wanted to say, but still later, we can. We used the extralist cuing task to model this phenomenon, and across experiments we varied the strength, direction, and directness of the relationship between the retrieval cues and the targeted information. Disruption was varied by switching attention to a different task before testing and by changing the testing context. Such disruptions reduced recall for the target and its implicitly activated memories. Following a disruption, stronger cues that were related to the target or to both the target and its implicit memories were more effective than those that were related to implicit memories. The findings were consistent with a model of long-term working memory that attributes forgetting to a loss of access to what has been activated, which loss is relative to the strength of the retrieval cue. Decay alone does not explain the results, indicating that many models of working memory need to be revised to take the nature of retrieval cues into account.

Attention↗
PubMed2003

Are implicitly activated associates selectively activated?

What constitutes a word's associative past? Words differ in how many associates they activate in memory and, following a brief encounter, those with fewer associates are more likely to be recalled in the presence of related cues. The issue addressed in the present article is whether associative set size effects are produced through the selective activation of strong associates or through the activation of both strong and weak associates. The set size of the strongest associates was varied factorially with the set size of the associates of these associates. We assume that associate set size indexes a word's weaker associates. Experiments 1 and 2 showed that recall varied inversely with both target and associate set sizes. Such results held over variations in study time and participant age. Experiment 3 showed that weak associates of the target had a greater effect on recall when there were more connections among the strongest associates in the set. The findings suggest that activation is not strength selective but includes both weak and strong associates.

Adult↗
PubMed2003

Spreading activation or spooky action at a distance?

How do preexisting connections among a word's associates facilitate its cued recall and recognition? A spreading-activation model assumes activation spreads to, among, and from a studied word's associates, and that its return is what strengthens its representation. An activation-at-a-distance model assumes strengthening is produced by the synchronous activation of the word's associates. The spread model predicts that connections among the studied word's associates will have a greater effect on memory when more of its associates return activation. The distance model predicts that total connections are important, not their direction. The results of cued recall experiments supported the distance model in showing that that connections among the associates facilitated recall regardless of the number of returning connections.

Adult↗
PubMed2002

Experiencing a word can prime its accessibility and its associative connections to related words.

This paper reports the results of manipulations of word features for the magnitude of priming effects. In Experiment 1, the printed frequency of the target words and the number of connections among their associates were varied, and during testing participants were given cues and asked to produce the first word to come to mind as rapidly as possible in implicit free association. Priming effects were greater for low-frequency words and for those with many connections among their associates. In Experiments 2 and 3, target words were presented under incidental or intentional learning conditions during study, and the presence of direct preexisting connections from target to cue and from cue to target was varied. Priming effects were greater when either connection was present, with each connection having additive effects. In Experiments 4 and 5, priming effects for indirect links (shared associates and mediators) were examined. The results of these experiments indicate that priming in free association depends on both the general accessibility of the target as a response and the strengthening of direct target-to-cue connections. These findings raise problems for theories that attribute priming only to target accessibility or only to target-to-cue association.

Cues↗