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M A Just

Publications and source records attributed to M A Just.

32 records · Page 2Linked to original sources
PubMed1993

The intensity dimension of thought: pupillometric indices of sentence processing.

This article explores the intensity of processing during sentence comprehension by measuring pupillary response during reading. Two experiments contrast the processing of simpler versus more complex sentences. The two more complex sentence types, object-relative center-embedded sentences and filler-gap sentences, not only take longer to process than their simpler counterparts, but they also produce a larger change in pupil diameter. We propose that the pupillary response is an indicator of how intensely the processing system is operating. The more complex sentences evoke some intense processing at the point in the sentence where a syntactic complexity is first encountered. The gaze durations at these points are elevated, indicating the immediate response to the demand of the syntactic processing. The pupil then starts to dilate, reaching a maximal diameter approximately 1.3 s later. The results from these various performance measures are integrated within a resource-limited computational model of comprehension. The paper develops a model of comprehension that includes an intensity dimension of thought, drawing a correspondence between the computational model's consumption of resources and the human pupillary response.

Adult↗
PubMed1992

Working memory constraints on the processing of syntactic ambiguity.

We propose a model that explains how the working-memory capacity of a comprehender can constrain syntactic parsing and thereby affect the processing of syntactic ambiguities. The model's predictions are examined in four experiments that measure the reading times for two constructions that contain a temporary syntactic ambiguity. An example of the syntactic ambiguity is The soldiers warned about the dangers . . . ; the verb warned may either be the main verb, in which case soldiers is the agent; or the verb warned may introduce a relative clause, in which case soldiers is the patient of warned rather than the agent, as in The soldiers warned about the dangers conducted the midnight raid. The model proposes that both alternative interpretations of warned are initially activated. However, the duration for which both interpretations are maintained depends, in part, on the reader's working-memory capacity, which can be assessed by the Reading Span task (Daneman & Carpenter, 1980). The word-by-word reading times indicate that all subjects do additional processing after encountering an ambiguity, suggesting that they generate both representations. Furthermore, readers with larger working-memory capacities maintain both representations for some period of time (several words), whereas readers with smaller working-memory capacities revert to maintaining only the more likely representation.

Adult↗
PubMed1992

A capacity theory of comprehension: individual differences in working memory.

A theory of the way working memory capacity constrains comprehension is proposed. The theory proposes that both processing and storage are mediated by activation and that the total amount of activation available in working memory varies among individuals. Individual differences in working memory capacity for language can account for qualitative and quantitative differences among college-age adults in several aspects of language comprehension. One aspect is syntactic modularity: The larger capacity of some individuals permits interaction among syntactic and pragmatic information, so that their syntactic processes are not informationally encapsulated. Another aspect is syntactic ambiguity: The larger capacity of some individuals permits them to maintain multiple interpretations. The theory is instantiated as a production system model in which the amount of activation available to the model affects how it adapts to the transient computational and storage demands that occur in comprehension.

Concept Formation↗
PubMed1990

What one intelligence test measures: a theoretical account of the processing in the Raven Progressive Matrices Test.

The cognitive processes in a widely used, nonverbal test of analytic intelligence, the Raven Progressive Matrices Test (Raven, 1962), are analyzed in terms of which processes distinguish between higher scoring and lower scoring subjects and which processes are common to all subjects and all items on the test. The analysis is based on detailed performance characteristics, such as verbal protocols, eye-fixation patterns, and errors. The theory is expressed as a pair of computer simulation models that perform like the median or best college students in the sample. The processing characteristic common to all subjects is an incremental, reiterative strategy for encoding and inducing the regularities in each problem. The processes that distinguish among individuals are primarily the ability to induce abstract relations and the ability to dynamically manage a large set of problem-solving goals in working memory.

Adult↗
PubMed1989

Changes in activation levels with negation.

Three experiments investigated the effects of negation during on-line language processing. It was hypothesized that negation of a noun (e.g., no bread) would affect the activation level of the mental representation of that noun. Experiment 1 manipulated the location of the negation in sentences that were followed by a probe recognition task. Subjects were slower to indicate that a probe had been in the sentence when the probe corresponded to a negated noun. Experiment 2 replicated these results with a probe naming task. Experiment 3 replicated the result that reading the phrase no bread inhibits responses to bread in the probe task but found no evidence of inhibition of the response to an associate probe, such as butter. The results of these three studies suggest that negation affects the discourse focus of a noun phrase, and hence the activation level of its representation.

Adult↗
PubMed1982

Paradigms and processes in reading comprehension.

This article compares several methods of presenting text, including a new paradigm that produces reading-time data with many of the characteristics of naturally occurring eye-fixation data. In the new paradigm, called the moving window condition, a reader presses a button to see each successive work in a text, and the previous work is removed when a new work appears. The words appear in the same position that they would in normal test, and word-length information is available in peripheral vision. The results are qualitatively and quantitatively compared to the results obtained by monitoring the eye fixations of subjects reading normal text. The word-level effects are generally similar. Readers pause longer on longer words, on less frequent words, on words that introduce a new topic, and at ends of sentences. The results suggest that readers initiate thr processing of each word as soon as they encounter it rather than buffer words and delay processing. Also considered are two other reading-time paradigms, one in which words are cumulatively displayed on the screen and one in which each successive word is presented at the same location on the screen. Finally, we consider how the tendency to immediately process text might interact with other techniques for text presentation, such as the rapid serial visual presentation (RSVP) condition, and we generate predictions about the nature and limits of the method.

Eye Movements↗
PubMed1978

Normalization of irrelevant dimensions in stimulus comparisons.

When subjects compared two multidimensional stimuli with respect to a single (relevant) dimension in a same-different task, variation in the irrelevant dimension systematically affected reaction times. For same trials, reaction times increased monotonically with the amount of disparity between the stimuli on the irrelevant dimension. The dimensions were heights and widths of ellipses or hues and tints of color patches. The results were interpreted in terms of a normalization process that internally transforms the irrelevant dimensions of the two stimuli until they are equal. The amount of normalization, and hence same reaction time, increased with increasing disparity on the irrelevant dimension. These results suggest that in order to decide that two objects are equivalent in some criterial respect, it is often necessary to normalize irrelevant disparities.

Color Perception↗
PubMed1977

A comparison of aphasic and normal adults in a sentence-verification task.

This study showed that in certain sentence-processing tasks, aphasics fail to perform correctly because they fail to execute particular mental operations. A straightforward information-processing model describes the mental processes that are used in deciding whether a sentence is true or false of an accompanying picture. The aphasics' performance, interpreted in light of the model, indicates what step in their processing is not operating properly in this task.

Aphasia↗
PubMed1975

The semantics of locative information in pictures and mental images.

Three experiments examined how people compare sentences about spatial location to pictures and images. Previous investigations have found that people are faster at judging relative location when the description contains the word above or right than when it contains the word below or left. Expt I showed that this asymmetry persisted when the words were replaced by arrows, indicating that the effect is not specific to particular lexical items. Expt. II showed the asymmetry persisted even when the response latency did not iclude the time to encode the description, indicating that the asymmetry does not lie in the description-encoding stage. Finally, Expt. III investigated how people compare sentences to information from a previously memorized picture. In this situation, the usual asymmetry was not present. The three studies suggest that the asymmetry arises from the way descriptions influence the encoding of perceptual events. The results also show that the information encoded in a mental representation of a picture is ordered such that certain features can be access-d more quickly than others. However, the same features are equally quickly accessed in a picture that is physically present.

Form Perception↗