Interrogative suggestibility: The effects of sleep deprivation and relationship with field dependence

Suggestibility (yield) scores on the first Gudjonsson Suggestibility Scale were found to correlate significantly with field dependence, as measured by the Finding Embedded Figures Test. Sleep-deprived subjects, while scoring worse on story memory, reaction time, POMS vigour–energetic and POMS confusion than controls, did not show any increase in yielding to suggestive questions. Upon answering the questions again after negative feedback, however, sleep-deprived subjects shifted their responses to questions significantly more than did controls. The results are interpreted in terms of sleep loss increasing the variability of performance.     

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.     

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.     

The development of visual and auditory selective attention using the central-incidental paradigm

Analogous auditory and visual central-incidental learning tasks were administered to 24 second-, fourth-, and sixth-grade and college-age subjects to study the effects of modality of presentation on memory for central and incidental stimulus materials. There was no strong evidence to indicate that modality of presentation was an important factor in the development of selective attention. Central task learning increased with age for both auditory and visual presentations; incidental learning declined at the oldest age level for both auditory and visual tasks. The serial position analysis revealed that the observed developmental increase in recall performance was due primarily to differences in the initial serial positions. The use of active strategies for focusing attention on the relevant stimulus materials seemed to be the crucial determinant of level of performance.     

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.     

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.     

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.