Sentence processing: Evidence against the serial,independent stage assumption

The assumption that the processing stages involved in sentence comprehension are serially and independently executed was tested in two separate experiments using two new sentence types. One experiment was a sentence-picture verification task, the other was not. In Experiment I, subjects viewed sentences such as It's false that the dots are red and indicated, by pressing the appropriate response key, which of two colors would make the sentence true. In Experiment II, subjects verified sentences such as It isn't true that the dots aren't red against pictures of colored dots. On the strength of Sternberg's additive factor method, present findings challenge the validity of the serial, independent stage assumption, and results are alternatively discussed in terms of a capacity sharing model.This research was supported by PHS research grant MH 23401 to Sam Glucksberg, principal investigator.     

Separable neural components in the processing of black and white faces

In a study of the neural components of automatic and controlled social evaluation, White participants viewed Black and White faces during event-related functional magnetic resonance imaging. When the faces were presented for 30 ms, activation in the amygdala-a brain region associated with emotion-was greater for Black than for White faces. When the faces were presented for 525 ms, this difference was significantly reduced, and regions of frontal cortex associated with control and regulation showed greater activation for Black than White faces. Furthermore, greater race bias on an indirect behavioral measure was correlated with greater difference in amygdala activation between Black and White faces, and frontal activity predicted a reduction in Black-White differences in amygdala activity from the 30-ms to the 525-ms condition. These results provide evidence for neural distinctions between automatic and more controlled processing of social groups, and suggest that controlled processes may modulate automatic evaluation.     

Evidence for independent processing of subjective contour brightness and sharpness.

Subjective contours have been of considerable interest because of their importance to theories and physiological models of form perception. In particular, they have recently been characterized as the result of magnocellular cortical processing. There is, however, a paucity of parametric data relating to basic psychophysical parameters in this field. Two experiments are reported in which the roles of subjective contour size, retinal eccentricity, and flicker rate in subjective contour salience were investigated. Eleven observers estimated subjective contour magnitude using an Ehrenstein configuration. Configurations ranging in size from 0.25 to 3 deg were presented to three retinal loci (fovea, 2 deg, and 4 deg) at flicker rates ranging from 5 to 15 Hz. Subjective contour brightness and distinctness were measured separately. Brightness was greatest at a subjective contour size of about 1.25 deg, at flicker rates of 5-7 Hz, and at 3 deg peripheral for all flicker rates and all but the smallest stimulus sizes. Distinctness decreased with eccentricity and flicker, but remained high at small diameters (thus implicating spatially sensitive mechanisms). Taken together, the results support a magnocellular processing of subjective contours with respect to brightness, but also suggest that there is a parvocellular contribution to subjective contour sharpness.     

Countermanding saccades: evidence against independent processing of go and stop signals

In a stop signal paradigm, subjects were instructed to make a saccade to a visual target appearing left or right of the fixation point. In 25% of the trials, an auditory stop signal was presented after a variable delay that required the subject to inhibit the saccade. Observed saccadic response times in stop failure trials were longer than predicted by Logan and Cowan's (1984) race model. Saccadic response time and amplitude decreased with the time between stop signal presentation and saccade execution, suggesting an inhibitory effect between the stop signal and the go signal processes that is not compatible with an independent race assumption. Moreover, countermanding a saccade was more difficult when stop and go signals appeared at the same location.     

Divided attention between lyrics and tunes of operatic songs: Evidence for independent processing

Excerpts from French operatic songs were used to evaluate the extent to which language and music compete for processing resources. Do these two dimensions conflict? Are they integrated into a single percept? Or are they independent? The final word of each excerpt was either semantically congruous or incongruous relative to the prior linguistic context and was sung either in or out of key. Participants were asked to detect either the semantic or the melodic incongruity (single task) or both (dual task). We predicted a dual-task deficit if these tasks conflicted and no deficit if they were either independent or integrated. In order to distinguish between these last two outcomes, trial-by-trial contingency analyses were also computed, predicting no correlation if the tasks were conflicting or independent, a positive correlation under the assumption of integration and a negative correlation if dividing attention is impossible. Our results show similar levels of performance in single and dual tasks and no correlation between dual-task judgments, thus suggesting that semantic and melodic aspects of language are processed by independent systems. In addition, a comparison between musicians and nonmusicians shows that these conclusions are independent of musical expertise.     

DAPs of black and white juvenile incarcerates

Two groups of male juvenile incarcerates were separated on the basis of race, matched in terms of age, recidivism, and intelligence test scores, and given a human figure drawing task. Figures drawn were male and female. The drawings were scored on 14 emotional indicators. The results of the present study offer little consistent or conclusive support for the hypothesis that differences influenced by race can be found in the projective drawings of black and white subjects. The commonly held impressions that there are more incidences of neurotic or psychotic features in the projective tests of black subjects and that the projective drawings of black subjects are generally inferior to the projective drawings of white subjects were not supported by the present study.     

Holistic face processing can be independent of gaze behaviour: Evidence from the composite face illusion

People tend to perceive identical top halves (i.e. above the nose) of two face stimuli as being different when they are aligned with distinct bottom halves. This composite face illusion is generally considered as the most compelling evidence that facial features are integrated into a holistic representation. Here, we recorded eye‐movements during the composite face illusion in a delayed matching task of top halves of faces. Behavioural results showed a strong composite face effect, participants making more mistakes and taking longer time to match two identical top halves of faces when they were aligned (vs. misaligned) with different bottom halves. Importantly, fixation sites and eye‐movements were virtually identical when the top and bottom parts were aligned (composite illusion) or misaligned (no illusion), indicating that holistic face processing can be independent of gaze behaviour. These findings reinforce the view that holistic representations of individual faces can be extracted early on from information at a relatively coarse scale, independently of overt attention.     

Repeating the target neither speeds nor slows its detection: Evidence for independent channels in letter processing

A target letter at a predesignated location typically is identified less readily when extraneous letters are added to the display. This disruption has been attributed to lateral interference via interactive or inhibitory channels or to attempts to encode the string as a unit. In the present study, subjects saw a single letter (e.g., B), a repeated-letter string (e.g., BBBB), or an extraneous-letters string (e.g., BCLD) and had to decide whether the leftmost letter in the string matched a target letter. Since trials were blocked by string type, letter position did not have to be discriminated on repeated-letter trials, nor was response competition present on those trials. With normal letter spacing, RT was virtually the same on repeated-letter trials as on single-letter trials. (Increasing the letter spacing in Experiment 3 did produce a slight, but nonsignificant, 22-msec increment on the repeated-letter trials.) The results indicate that individual letters are perceived as such just as well when presented in a group as when presented individually and thus provide support for the parallel, independent-channels model.     

Predictors of scientific majors for black and white college students

The differences in the personality and social backgrounds of science and non-science majors were assessed for 91 black and 109 white natural, social, and nonscience college majors. Subjects were administered the 16PF, Bem Sex-Role Inventory, and the Attitude Toward Women Scale, and data were collected on birth order, number of siblings, and social class level. Natural science majors were of a higher social class, had higher intelligence test scores, were more reserved, sober, practical, and male sex-role oriented than the social and non-science majors. Blacks and females resembled their white or male counterparts when categorized by college major.     

Socialization and career orientation among black and white college women

In a study of career orientation among black and white college women, support was found for hypotheses derived from postulates of Rotter's Social Learning Theory. Compared to whites, (1) blacks were less likely to expect the level of work involvement preferred; (2) blacks expected more employment; and (3) blacks were more likely to prefer less employment than they realistically expected. Antecedents of career expectation were categorized as internal, external, or neutral. As hypothesized, variables expressive of external control predicted level of career expectation among blacks, whereas variables expressive of internal control predicted high career expectations among whites.     

Facial attractiveness and juvenile delinquency among black and white offenders

Facial pictures of black and white delinquents were significantly less attractive than pictures of corresponding groups of high school students, as judged by same-race raters. Significant differences were found among the white delinquents, but not among the black, for Quay's four behavioral dimensions of delinquency. Black delinquents were significantly darker in skin color than the black high school students, and lightness of skin color was positively correlated with physical attractiveness ratings made by both black and white raters, indicating that neither race has yet assimilated the saying black is beautiful. This and other evidence suggest that facial attractiveness may be causal in delinquency.These studies were conducted with the cooperation of the staff of the Robert F. Kennedy Youth Center, Federal Bureau of Prisons, U.S. Department of Justice. The center is not responsible for the contents of this report; the report does not necessarily represent the Center's views. The portion of this paper dealing with the white offenders was presented at the meeting of the Eastern Psychological Association, Boston, Massachusetts, April 1972.The authors would like to thank Hayne W. Reese for his assistance.     

Pictures and anaphora: Evidence for independent processes

Pictures enhance our comprehension of written texts, but the perceptual and cognitive processes that underlie this effect have not been identified. Because integrating the information contained in a text places demands on working memory, the effect of a picture may be to expand the functional capacity of working memory and thereby to facilitate comprehension. Reasoning thus, we predicted that the availability of a diagram would interact with the difficulty of resolving anaphoric references in texts. The resolution of an anaphor distant from its antecedent (which should stress working memory) should benefit greatly from the presentation of a picture, whereas the resolution of an anaphor near to its antecedent should benefit less from the presentation of a picture. Picture availability and distance separating the anaphor from its antecedent were manipulated in experiments involving both cumulative and moving window presentations of texts. Although picture presence and ease of anaphor resolution significantly improved comprehension of the material, no evidence was found for an interaction of these factors. The results are interpreted as consistent both with dual code theory and with aspects of working memory management that do not involve anaphor resolution.     

Stimulus-specific processing consequences of pattern goodness

Two issues concerning the effects of visual pattern goodness on information processing time were investigated: the role of memory vs. encoding and the role of individual stimulus goodness vs. stimulus similarity. A sequential “same-different” task was used to provide differentiation of target item or memory effects from display item or encoding effects. Experiment 1 used four alternative stimuli in each block of trials. The results showed that good patterns were processed faster than poor patterns for both “same” and “different” responses. Furthermore, the goodness of the target item had a greater effect on reaction time than did the goodness of the display item, indicating that memory is more important than encoding in producing faster processing of good stimuli. Effects of interstimulus similarity on processing time were minimal, although isolation of good stimuli in a similarity space could explain many of the results. Experiment 2 replicated the results of Experiment 1, despite the fact that differences in similarity space had been minimized by using only two alternative stimuli in each block. In addition, the speed of processing a “same” pair was essentially independent of the particular alternative stimulus in a block. These results suggest that in this task, there is a processing advantage for good stimuli that is stimulus specific, with the effect operating primarily in memory.     

Parallel pattern processing and visual agnosia.

A series of visual search experiments are reported examining pattern processing in a visual agnosic patient. We examined search for targets defined by: (I) the combination of their features relative to homogeneous distractors; (2) the combination of their features relative to heterogeneous distractors; and (3) a single feature difference relative to the distractors (their orientation). Normal subjects demonstrate evidence of spatially parallel search when combined-feature targets are detected against homogeneous distractors, and when targets are defined by a salient feature difference. There are non-linear effects of the number of distractors present, and absent responses can be as fast as present. In contrast, search times for combined-feature targets amongst heterogeneous distractors increase linearly with display size, with the slope for absent responses about twice that for present. The contrast between search for combined-feature targets amongst homogeneous and heterogeneous distractors can be attributed to the effects of grouping between distractors and between distractors and targets (Duncan & Humphreys, 1989, 1992; Humphreys & Muller, in press). Grouping between homogeneous distractors facilitates search. An agnosic patient, HJA, showed normal search functions for single-feature targets and for combined-feature targets amongst heterogeneous distractors. However, he was impaired at search for combined-feature targets amongst homogeneous distractors. This suggests that HJA is selectively impaired at grouping conjunctions of form features. The relations between HJA's agnosia and his problem in the parallel grouping of form conjunctions are discussed, as are the implications of the work for understanding normal vision.