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G McKoon

Publications and source records attributed to G McKoon.

At least 37 records · Page 2Linked to original sources
PubMed1995

Bias in the priming of object decisions.

Seven experiments examined priming effects for 3-dimensional line drawings in the object decision task. One of the most important previous findings about object decisions has been that the decision about a possible object is primed by previous presentation of the object, but the decision about an impossible object is not. Through the use of manipulations that can eliminate processes that retrieve episodic information (response time deadlines, memory load, forced choice, and similarity), equal size effects on impossible and possible objects were obtained. This is interpreted to mean that priming effects reflect a bias to respond "possible," which can be opposed for impossible objects by episodic information so as to yield the approximately null priming effect for impossible objects found in past experiments.

Decision Making↗
PubMed1995

Sequential effects in lexical decision: tests of compound-cue retrieval theory.

According to compound-cue retrieval theories, responses in lexical decision are determined by a passive process that matches a compound of the items in short-term memory against all of the information in long-term memory. Because responses depend on other items in short-term memory in addition to the target item about which a lexical decision is required, compound-cue theories must predict sequential effects and priming effects. For example, a nonword preceding a target should slow responses to the target, and a prime word related to a target word can affect responses to the target even when another item intervenes between them. In this article, the results of 4 experiments are presented and sequential effects are shown to be in accord with compound-cue theory.

Adult↗
PubMed1995

How should implicit memory phenomena be modeled?

In a reply to R. Ratcliff and G. McKoon's (1995a) article on bias in the object decision task, D. L. Schacter and L. A. Cooper (1995) critiqued their theoretical arguments and presented an updated view of priming in the object decision task. In the present article, the updated view is examined in detail, and it is questioned whether Schacter and Cooper's explanation of the data is sufficiently articulated to be falsifiable. It is also argued in the present article that evidence from other research domains is not directly supportive of the memory systems hypothesis and that the statistical power available in data from object decision experiments is not great enough to test some relevant hypotheses. Finally, the bias hypothesis (Ratcliff & McKoon, 1995a) is elaborated to show that it requires a particular pattern of experimental results and that it serves as a target phenomenon for modeling.

Decision Making↗
PubMed1994

Empirical generality of data from recognition memory receiver-operating characteristic functions and implications for the global memory models.

The experiments presented in this article examined the slope of the zeta-ROC (receiver-operating characteristic) function for recognition memory. The slope was examined as a function of strength and the variables study time, list length, word frequency, and category membership. For normal distributions of familiarity, the slope of the zeta-ROC is the ratio of the new-item to old-item standard deviations. R. Ratcliff, C.-F. Sheu, and S. D. Gronlund (1992) found that the slope was constant within standard error as a function of strength of encoding, which is inconsistent with the predictions of the global memory models. The results presented here extend this finding: The slope was constant as a function of strength of encoding, list length, and the number of related items from a category in the study list. Word frequency did affect the slope, but within a frequency class the slope was constant as a function of strength. The implications of these data for the global memory models, the attention likelihood model, and variants of these models are discussed.

Attention↗
PubMed1994

Retrieving information from memory: spreading-activation theories versus compound-cue theories.

McNamara (1992a) attacked compound-cue theories on a number of grounds. Using free association as a measure of distance between concepts in memory, he argued that compound-cue theories cannot explain mediated priming effects. The authors show that free-association production probabilities do not accurately predict priming effects, either directly or in the context of current spreading-activation models, and so remove the basis for McNamara's criticism. McNamara also claimed that compound-cue theories cannot account for the sequential effects of items that precede a target on responses to the target, but the authors show that sequential effects are consistent with compound-cue models if the target item is weighted more heavily than preceding items in the calculation of familiarity that determines response time and accuracy for the target. It is concluded that, although compound-cue and spreading-activation theories are both consistent with available data, the compound-cue theory, having less freedom, has passed more stringent tests.

Attention↗
PubMed1994

Testing theories of language processing: an empirical investigation of the on-line lexical decision task.

On-line lexical decision has been used to test major theoretical hypotheses about language comprehension. Contrary to several current models, A. Sharkey and N. Sharkey (1992) found that a word in a sentence did not give facilitation to an immediately following, highly associated test item. In this article it is shown that such facilitation can be obtained. Other theories have proposed that syntactic processes supply antecedents for implicit anaphors. In using a test item that was an associate of the antecedent of the anaphor, the authors were unable to replicate previous findings of facilitation at but not before the site of the anaphor. Across 9 experiments, obtaining facilitation depended on the choice of control condition. This dependency raises questions about previous on-line lexical decision results that have been used to support the immediacy of syntactic processing.

Cognition↗
PubMed1994

Sentential context and on-line lexical decision.

J. L. Nicol and D. Swinney (1989) reported that lexical decision response times to a test word that was related to the implicit object of a verb were faster, when tested immediately after the verb, than response times to a control test word. They concluded from this result that the relation between the implicit object and the verb was understood during comprehension. In G. McKoon, R. Ratcliff, and G. Ward (1994), another interpretation was suggested, that the faster lexical decision response times were due to the better semantic-pragmatic fit of the related test words to the sentential contexts, and experimental data were presented to support this interpretation. In response, J.L. Nicol, J. D. Fodor, and D. Swinney (1994) pointed out some possible problems with these experiments. The experiment presented in this article undermines their arguments. By using sentences in which there was no implicit object, exactly the same pattern of results was found as originally reported by J. L. Nicol and D. Swinney, thereby implicating some factor other than syntactic processing of an implicit object as an explanation of their finding.

Cognition↗
PubMed1993

Discourse models, pronoun resolution, and the implicit causality of verbs.

Some interpersonal verbs, such as admire and amaze, describe an action or property of one person (the reactor) that is necessarily a response to an action or property of another (the initiator). We hypothesized that these verbs make the initiator relatively more accessible in a comprehender's discourse model and that this change in relative accessibility aids identification of the referent of a pronoun in a subsequent because clause. We predicted that, as a result, subjects would be faster to recognize a character's name after a because clause that uses a pronoun to refer to that character than after one that refers to some other character. Four experiments confirmed this prediction. Three further experiments demonstrated the importance of the verb's causal structure and of the presence of the connective because to this result.

Adult↗
PubMed1992

Pronoun resolution and discourse models.

Psychological investigations of pronoun resolution have implicitly assumed that the processes involved automatically provide a unique referent for every pronoun. We challenge this assumption and propose a new framework for studying pronoun resolution. Drawing on advances in discourse representation and global memory modeling, this framework suggests that automatic processes may not always identify a unique referent for a pronoun. In 9 experiments, we demonstrate that, unlike noun anaphors, pronouns sometimes do not produce relative facilitation of their referents in comparison with nonreferents. We argue that research on pronoun resolution must consider the discourse contexts in which pronouns are likely to occur.

Attention↗
PubMed1992

Spreading activation versus compound cue accounts of priming: mediated priming revisited.

Spreading activation theories and compound cue theories have both been proposed as accounts of priming phenomena. According to spreading activation theories, the amount of activation that spreads between a prime and a target should be a function of the number of mediating links between the prime and target in a semantic network and the strengths of those links. The amount of activation should determine the amount of facilitation given by a prime to a target in lexical decision. To predict the amount of facilitation, it is necessary to measure the associative links between prime and target in memory. Free-association production probability has been the variable chosen in previous research for this measurement. However, in 3 experiments, the authors show priming effects that free-association production probabilities cannot easily predict. Instead, they argue that amount of priming depends on the familiarity of the prime and target as a compound, where the compound is formed by the simultaneous presence of the prime and target in short-term memory as a test item.

Adult↗
PubMed1992

Inference during reading.

Most current theories of text processing assume a constructionist view of inference processing. In this article, an alternative view is proposed, labeled the minimalist hypothesis. According to this hypothesis, the only inferences that are encoded automatically during reading are those that are based on easily available information, either from explicit statements in the text or from general knowledge, and those that are required to make statements in the text locally coherent. The minimalist hypothesis is shown to be supported by previous research and by the results of several new experiments. It is also argued that automatically encoded minimalist inferences provide the basic representation of textual information from which more goal-directed, purposeful inferences are constructed.

Attention↗
PubMed1989

Similarity information versus relational information: differences in the time course of retrieval.

Two experiments are reported that examine the time course of retrieval in a sentence matching procedure. Subjects learned lists of active and passive sentences and were tested with sentences in active or passive, correct or incorrect versions; for example, if "John hit Bill" was a studied sentence, "Bill hit John" would be an incorrect active test sentence. A response signal procedure was used so that accuracy could be measured as a function of time. The data show that sentences containing words from studied sentences are discriminable early in processing from sentences containing all new words, but discrimination of correct from incorrect versions of studied sentences occurs only later in processing (after 600-700 ms). These results demonstrate that different kinds of information are available at different points during the time course of retrieval and so suggest that modifications are required of models that provide only a unitary value for the amount of match between a test probe and information in memory. Early in processing, the growth of accuracy can be explained by a simple model that assumes independent contributions to total amount of match for each of the content words of a sentence, but this independent processing model cannot account for discrimination later in processing. Several, more general, memory models are examined with respect to their abilities to produce independent item information early in processing and relational information later in processing.

Humans↗
PubMed1989

Semantic associations and elaborative inference.

In this article, a theoretical framework is proposed for the inference processes that occur during reading. According to the framework, inferences can vary in the degree to which they are encoded. This notion is supported by three experiments in this article that show that degree of encoding can depend on the amount of semantic-associative information available to support the inference processes. In the experiments, test words that express possible inferences from texts are presented for recognition. When testing is delayed, with other texts and test items intervening between a text and its test word, performance depends on the amount of semantic-associative information in the text. If the inferences represented by the test words are not supported by semantic associates in the text, they appear to be only minimally encoded (replicating McKoon & Ratcliff, 1986), but if they are supported by semantic associates, they are strongly encoded. With immediate testing, only 250 ms after the text, performance is shown to depend on semantic-associative information, not on textual information. This suggests that it is the fast availability of semantic information that allows it to support inference processes.

Adult↗
PubMed1989

A bias interpretation of facilitation in perceptual identification.

In a typical perceptual identification task, a word is presented for a few milliseconds and masked; then subjects are asked to report the word. It has been found that an earlier presentation of the test word will improve identification of the test word by as much as 30%. In addition, this facilitation has been shown to be preserved under amnesia. In this article we examine a fundamental question: Is the facilitation the result of bias toward the earlier presented item, an improvement in perceptual sensitivity, or both? The experiments presented here use a forced choice procedure to show that prior presentation of an item biases the subject to choose that item but does not improve discriminability. This result is obtained when the distractor items are visually similar to the target items. When distractors are dissimilar, earlier presentation affects neither bias nor discriminability. Two models of word identification are examined in light of the bias effects, and implications for understanding savings in amnesia are also examined.

Adult↗
PubMed1988

Contextually relevant aspects of meaning.

A series of six experiments investigated whether inferences about contextually relevant aspects of meaning were encoded into memory during reading. In all the experiments, subjects studied short paragraphs. Then, test sentences were presented that expressed relevant aspects of meaning that had not been explicitly stated in the paragraphs. For example, for a paragraph about searching for the correct color to paint a picture of a tomato, a relevant aspect of meaning would be that tomatoes are red. The test sentences were presented either immediately following the relevant paragraph or after a delay. With immediate testing, it was argued that the facilitation obtained in verification latency could result from processes occurring either when the context was read or when the test sentence was verified. With delayed testing, evidence was found to support the hypothesis that contextually relevant aspects of meaning are incorporated into the memory representation of the paragraph, but such evidence was obtained only when the retrieval environment encouraged the use of newly learned information in the decision process on the test sentence.

Cognition↗
PubMed1986

Automatic activation of episodic information in a semantic memory task.

Four experiments are presented in which priming between newly learned associates and priming between well-known associates were examined in lexical decision. All four experiments found priming between newly learned associates, including conditions in which the Stimulus Onset Asynchrony (SOA) between prime and target was short (150 ms) and in which the probability was low (1/12) that the prime and target of a pair would be associated to each other. It was concluded, contrary to suggestions by Carroll and Kirsner (1982) and Tulving (1983), that newly learned associates can prime each other, and that they can do so at short SOAs.

Association Learning↗
PubMed1986

Inferences about predictable events.

If someone falls off of a 14th story roof, very predictably death will result. The conditions under which readers appear to infer such predictable outcomes were examined with three different retrieval paradigms: immediate recognition test, cued recall, and priming in word recognition. On immediate test, responses to a word representing the implicit outcome (e.g., dead) were slow, but on delayed test these responses were slow or inaccurate only when primed by an explicitly stated word. However, the word expressing the predictable outcome did function as an effective recall cue. Results suggest that readers encode these inferences into memory only minimally, but that they can make use of a cue word that represents the inference (e.g., dead) both at the time of an immediate test and in delayed cued recall.

Cognition↗