Comments on the motivational status of self-esteem in social identity and intergroup discrimination

The background and development of motivational hypotheses in social identity theory are examined, revealing two general motives for intergroup discrimination: a desire for cognitive coherence, or good structure; and a need for positive self-esteem. The latter (self-esteem hypothesis: SEH) has received most attention. Both the theoretical and empirical bases of the SEH are largely rooted in research using the minimal group paradigm. However, it remains unclear whether self-esteem is to be considered primarily as a cause or an effect of discrimination. When real social groups are considered the SEH appears to provide only a partial explanation, and a variety of more or less powerful alternative social motives may underlie discriminatory behaviour. We explore some social-structural, individual and interpersonal limits to the SEH, and we call for an awareness of these motives and a re-examination of the good-structure thesis. The SEH, as it stands, provides only a partial contribution to our understanding of the relationship between social identity and discriminatory intergroup behaviour.     

Art Media and the Sense Modalities: Tactile Pictures

It is widely assumed that the art media can be individuated with reference to the sense modalities. Different art media are perceived by means of different sense modalities, and this tells us what properties of each medium are aesthetically relevant. The case of pictures appears to fit this principle well, for pictures are deemed purely and paradigmatically visual representations. However, recent psychological studies show that congenitally and early blind people have the ability to interpret and make raised-line drawings through touch. This shows that pictures are not essentially visual representations. The view that pictures are essentially visual follows from influential views of the nature of depiction and of the nature of vision that are mistaken. By rooting out the mistake, we learn something about pictures, something about vision, and something about the doctrine that art media are individuated by the sense modalities.     

Dividing attention between auditory and visual perception

To what extent is simultaneous visual and auditory perception subject to capacity limitations and attentional control? Two experiments addressed this question by asking observers to recognize test tones and test letters under selective and divided attention. In Experiment 1, both stimuli occurred on each trial, but subjects were cued in advance to process just one or both of the stimuli. In Experiment 2, subjects processed one stimulus and then the other or processed both stimuli simultaneously. Processing time was controlled using a backward recognition masking task. A significant, but small, attention effect was found in both experiments. The present positive results weaken the interpretation that previous attentional effects were due to the particular duration judgment task that was employed. The answer to the question addressed by the experiments appears to be that the degree of capacity limitations and attentional control during visual and auditory perception is small but significant.     

Real-time speech synthesis

This paper describes how a speech synthesizer can be controlled by a small computer in real time. The synthesizer allows precise control of the speech output that is necessary for experimental purposes. The control information is computed in real time during synthesis in order to reduce data storage. The properties of the synthesizer and the control program are prsented along with an example of the speech synthesis.     

Categorical results do not imply categorical perception

Categorical perception refers to the ability to discriminate between- but not within-category differences along a stimulus continuum. Although categorical perception was thought to be unique to speech, recent studies have yielded similar results with nonspeech continua. The results are usually interpreted in terms of categorical, as opposed to continuous, perception of both speech and nonspeech continua. In contrast, we argue that these continua are perceived continuously, although they are characterized by relatively large increases in discrim-inability near the category boundary. To support this argument, the amplitude rise time of a tone was varied to produce either an increase or a decrease in the intensity during the initial portion of the tone. A bipolar continuum of onset times increasing and decreasing in amplitude yielded traditional categorical results. However, when only half of this continuum was tested, subjects perceived the same sounds continuously. The finding of traditional categorical results along the bipolar continuum, when the sounds were shown to be perceived continuously in another context, argues against the use of traditional categorical results as evidence for categorical perception.     

The Dysfunctional Attitude Scale: How well can it measure depressive thinking?

The Dysfunctional Attitude Scale (DAS) was designed to measure patterns of maladaptive thinking held by depressed individuals. Despite its wide use as a research and clinical tool, only a few studies to date were designed to examine its psychometric properties in a clinically depressed population. Moreover, problems of low sample size and limited tests of validity call these findings into question. The present study was designed to examine psychometric properties of the DAS in clinically depressed inpatients and in nondepressed clinical controls. Intertest correlations between the DAS parallel forms and between each form with total test scores ranged from r=.84 to r=.97. Intratest stability coefficients were r=.88 to r=.97. Support for the DAS as a valid measure of dysfunctional cognitions in depressed patients was also indicated. Of those scoring high on the DAS, 73% received an independent RDC diagnosis of clinical depression, while only 36% of those receiving low DAS scores were so diagnosed.     

Typing letter strings varying in orthographic structure

Subjects typed six-letter strings varying in orthographic structure. Lexical status, word frequency, position-sensitive log bigram frequency, and regularity of letter sequencing were systematically varied. Cumulative reaction times (RTs) of the keystrokes were adequately described by a linear function of letter position in the test string. Overall, words were typed faster than nonwords, and regular strings faster than irregular strings. Although the effect of log bigram frequency was not significant, this variable interacted with regularity and word frequency. Post hoc analyses of performance on each of the 200 letter strings revealed significant effects of the number of irregularities, log bigram frequency, and log word frequency. Transition times between successive keystrokes were significantly longer for illegal than for legal letter transitions. These results are similar to previous findings on the role of orthographic structure in the perceptual recognition of letter strings and provide a more complete analysis of context effects in typing.     

The contribution of vowel duration,F0 contour,and frication duration as cues to the/juz/-/jus/distinction

A model was quantified to describe the integration of vowel duration, fricative duration, and fundamental frequency (F₀) contour as cues to final position fricatives differing in voicing. The basic assumptions are that perceived vowel duration and perceived frication duration are cues to the identity of final position fricatives and that both F₀ contour and vowel duration influence perceived vowel duration. Binary choice and rating responses to synthetic stimuli varying independently along the three dimensions were collected. The results were consistent with the assumption that F₀ contour operates by modifying perceived vowel duration, which is a direct cue. Unfortunately, the nature of the modification appears to be very similar in form to that which results from the integration of two independent cues in syllable identification. Therefore, the results do not allow a rejection of the idea that the perception of F₀ contour may directly cue the identity of final position fricatives.