Two stages in postcategorical filtering and selection

Memory &; Cognition - In a modified Stroop paradigm, Kahneman and Henik (1981) varied the spatial location of incompatible color words in relation to the position of the ink color to be named. A...     

Comprehension of directly and indirectly stated main ideas and details in discourse by brain-damaged and non-brain-damaged listeners

Aphasic, right-hemisphere-damaged, and non-brain-damaged subjects heard short narrative paragraphs. Each paragraph contained four main ideas and one or more details related to each main idea. After each paragraph was presented, subjects' comprehension and retention of main ideas and details from the paragraph were tested. Some of the test items directly restated information from paragraphs and others paraphrased information from paragraphs. All groups of subjects remembered main ideas better than they remembered details, and no group of subjects was significantly affected by whether test items directly or indirectly stated information from paragraphs. Disfluent aphasic and right-hemisphere-damaged subjects' overall paragraphs comprehension scores were not significantly poorer than those of non-brain-damaged subjects. Fluent and mixed aphasic subjects' overall paragraph comprehension scores were significantly worse than those of non-brain-damaged and right-hemisphere-damaged subjects. Token Test and Boston Diagnostic Aphasia Examination auditory comprehension scores did not predict aphasic subjects' paragraph comprehension scores. right-hemisphere-damaged subjects' overall paragraph comprehension scores were not significantly those of non-brain-damaged and right-hemisphere-damaged subjects. Token Test and Boston Diagnostic Aphasia Examination auditory comprehension scores did not predict aphasic subjects' paragraph comprehension scores.     

Comprehension of main ideas and details in coherent and noncoherent discourse by aphasic and nonaphasic listeners

Aphasic and nonaphasic listeners' comprehension of main ideas and details within coherent and noncoherent narrative discourse was examined. Coherent paragraphs contained one topic to which all sentences in the paragraph related. Noncoherent paragraphs contained a change in topic with every third or fourth sentence. Each paragraph contained four main ideas and one or more details that related to each main idea. Listeners' responses to yes/no questions following each paragraph yielded the following results: (1) Nonaphasic listeners comprehended the paragraphs better than aphasic listeners. (2) Both aphasic and nonaphasic listeners comprehended main ideas better than they comprehended details. (3) Coherence did not affect comprehension of main ideas for either group. (4) Coherence did not affect comprehension of details by nonaphasic subjects. (5) Coherence affected comprehension of details by aphasic subjects, and their comprehension of details in coherent paragraphs was worse than their comprehension of details in noncoherent paragraphs. There was no significant correlation between Token Test scores and measures of paragraph comprehension.     

Sensitivity to lexical denotation and connotation in brain-damaged patients: A double dissociation?

Sets of words can be grouped in terms of their denotation (cold and warm both refer literally to temperature) or in terms of their connotation (cold and warm connote remoteness and intimacy, respectively). To assess whether these two facets of meaning are dissociable, unilaterally left- and right-hemisphere-damaged patients were presented with word triads and asked to group together the two words that were closest in meaning. Right-hemisphere-damaged patients showed a preserved sensitivity to denotation, and a selective insensitivity to connotative facets of meanings. In contrast, left-hemisphere-damaged patients exhibited a preserved sensitivity to connotation as well as a selective insensitivity to denotative aspects of meanings. Inasmuch as normal control subjects displayed a flexible sensitivity to both denotative and connotative aspects of meaning, the results suggest that unilateral brain damage selectively curtails use of one or the other major aspect of word meaning.     

The nature of the phonological disorder in conduction aphasia

Sequences of attempts to name pictured objects were used to examine phonological dysfunction in three diagnostic subgroups of aphasia. A prevalence of "phonologically-oriented sequences" (i.e., those sequences that contained only attempts with a phonological resemblance to the target word) was found to be a diagnostic criterion for conduction aphasia. When compared to a group of Broca's (n = 7) and Wernicke's (n = 5) aphasics, all the conduction aphasics (n = 6) produced proportionately more of such phonologically-oriented sequences on a picture naming test. An examination of the phonologically-oriented sequences produced by the conduction aphasics indicates that speech production in conduction aphasia involves dysfunction at an early stage of sound-encoding. The theoretical implications of this view are discussed.     

Automatic aftereffects in two-choice reaction time: a mathematical representation of some concepts

A mathematical model is developed to describe sequential effects in two-choice reaction time experiments with a short response-stimulus interval. Evidence is briefly discussed that in conditions with short response-stimulus intervals, automatic aftereffects dominate sequential effects, and the influence of subjective expectancy can be neglected. In these conditions the model premises three components of automatic aftereffects--facilitation, inhibition, and noise, with a common decay factor. Influence of response-stimulus interval and practice on sequential effects are examined and related to parameter changes in the proposed single-decay model. The decrease of automatic aftereffects with increasing response-stimulus interval is primarily ascribed to an increasing decay factor. The parameter representation of the model also clarifies the issue of the disappearance of automatic aftereffects with practice. It shows a gradual fading of inhibition in the initial stages of practice, together with a slower decrease of the facilitation effect. The single-decay model provides a satisfactory explanation for the processes involved in compatible two-choice reaction time with short response-stimulus interval.     

Auditory perception of breaking and bouncing events: a case study in ecological acoustics

The mechanical events of bouncing and breaking are acoustically specified by single versus multiple damped quasi-periodic pulse patterns, with an initial noise burst in the case of breaking. Subjects show high accuracy in categorizing natural tokens of bouncing and breaking glass as well as tokens constructed by adjusting only the temporal patterns of components, leaving their spectral properties constant. Differences in average spectral frequency are, therefore, not necessary for perceiving this contrast, though differences in spectral consistency over successive pulses may be important. Initial noise corresponding to glass rupture appears unnecessary to categorize breaking and bouncing. The data indicate that higher order temporal properties of the acoustic signal provide information for the auditory perception of these events.     

Integrating pictorial information across eye movements

Six experiments are reported dealing with the types of information integrated across eye movements in picture perception. A line drawing of an object was presented in peripheral vision, and subjects made an eye movement to it. During the saccade, the initially presented picture was replaced by another picture that the subject was instructed to name as quickly as possible. The relation between the stimulus on the first fixation and the stimulus on the second fixation was varied. Across the six experiments, there was about 100-130 ms facilitation when the pictures were identical compared with a control condition in which only the target location was specified on the first fixation. This finding clearly implies that information about the first picture facilitated naming the second picture. Changing the size of the picture from one fixation to the next had little effect on naming time. This result is consistent with work on reading and low-level visual processes in indicating that pictorial information is not integrated in a point-by-point manner in an integrated visual buffer. Moreover, only about 50 ms of the facilitation for identical pictures could be attributed to the pictures having the same name. When the pictures represented the same concept (e.g., two different pictures of a horse), there was a 90-ms facilitation effect that could have been the result of either the visual or conceptual similarity of the pictures. However, when the pictures had different names, only visual similarity produced facilitation. Moreover, when the pictures had different names, there appeared to be inhibition from the competing names. The results of all six experiments are consistent with a model in which the activation of both the visual features and the name of the picture seen on the first fixation survive the saccade and combine with the information extracted on the second fixation to produce identification and naming of the second picture.     

Awareness of the response after feedback training for changes in heart rate and sudomotor laterality

What is the relation between the ability to control visceral responding on a biofeedback task and the ability to report behaviors actually contributing to this performance? Subjects received biofeedback training for unidentified visceral responses and then gave written reports about what they had done to control the feedback displays. Independent judges were given these reports and, on the basis of knowledge about activities known to contribute to visceral activity, were asked to determine the visceral responses for which the subjects had been trained. The reports of subjects who succeeded at bidirectional control of heart rate (Experiment 1) or sudomotor laterality (Experiment 2) showed awareness of behaviors related to feedback as assessed by this procedure, whereas the reports of subjects who failed at bidirectional control did not. Subsequent experiments indicated that these results did not depend on a learning strategy that might have been specific to the initial studies. These findings call into question the view that people are unaware of what they have done to produce the response after training on biofeedback tasks. Earlier studies reporting lack of awareness in biofeedback are discussed in light of factors that affect the measurement of biofeedback learning and response awareness.     

Individual differences in loudness processing and loudness scales

Parameters of the psychophysical function for loudness (a 1000-Hz tone) were assessed for individual subjects in three experiments: (a) binaural loudness summation, (b) temporal loudness summation, and (c) judgments of loudness intervals. The loudness scales that underlay the additive binaural summation closely approximated S. S. Stevens's (1956) sone scale but were nonlinearly related to the scales that underlay the subtractive interval judgments, the latter approximating Garner's (1954) lambda scale. Interindividual differences in temporal summation were unrelated to differences in scaling performance or in binaural summation. Although the exponents of magnitude-estimation functions and the exponents underlying interval judgments varied considerably from subject to subject, exponents computed on the basis of underlying binaural summation varied less. The results suggest that interindividual variation in the exponent of magnitude-estimation functions largely reflects differences in the ways that subjects use numbers to describe loudnesses and that the sensory representations of loudness are fairly uniform, though probably not wholly uniform, among people with normal hearing. The magnitude of individual variation in at least one measure of auditory intensity processing, namely, temporal summation, seems at least as great as the magnitude of the variation in the underlying loudness scale.