Bill Jones

Perception of texture by vision and touch: multidimensionality and intersensory integration

A series of six experiments offers converging evidence that there is no fixed dominance hierarchy for the perception of textured patterns, and in doing so, highlights the importance of recognizing the multidimensionality of texture perception. The relative bias between vision and touch was reversed or considerably altered using both discrepancy and nondiscrepancy paradigms. This shift was achieved merely by directing observers to judge different dimensions of the same textured surface. Experiments 1, 4, and 5 showed relatively strong emphasis on visual as opposed to tactual cues regarding the spatial density of raised dot patterns. In contrast, Experiments 2, 3, and 6 demonstrated considerably greater emphasis on the tactual as opposed to visual cues when observers were instructed to judge the roughness of the same surfaces. The results of the experiments were discussed in terms of a modality appropriateness interpretation of intersensory bias. A weighted averaging model appeared to describe the nature of the intersensory integration process for both spatial density and roughness perception.

Cognitive activity and suggestions for analgesia in the reduction of reported pain.

Pain magnitude and pain tolerance for arm immersion in ice water were assessed during a baseline and posttest session. Before the posttest half the subjects received (and half did not receive) an analgesia suggestion. On the basis of their written testimony, subjects were classified as having either predominantly coped (e.g., imagined events inconsistent with pain; made positive self-statements) or predominantly exaggerated (e.g., worried about and exaggerated the noxious aspects of the situation) during each immersion. On both immersions copers reported less pain and exhibited higher pain tolerance than exaggerators. Moreover, the suggestion was associated with reductions in reported pain only when it transformed baseline exaggerators into posttest copers. Theoretical implications are discussed.

Signal detection theory and pain research

&NA; Rollman [13,14] has clearly raised important questions about the application of signal detection (TSD) procedures to the study of the perceived painfulness of stimuli. Researchers have often failed to realize that the discriminability of two usually painful stimuli need not be related to their reported painfulness. Thus indices of discrimination accuracy derived form TSD are logically (throughout necessarily empirically) independent of the analgesic properties of any treatment. However, Rollman misleadingly gives the impression that he is questioning the general validity of the application of TSD to answering questions in pain research. This is not the case. Procedures derived from TSD may play an important part in answering questions of interest to pain researchers especially as Rollman has exaggerated the practical difficulties associated with TSD experiments. It must be emphasized that there is no one TSD model as Rollman often seems to imply but a variety of models[5,9]. The usefulness of any model in any situation is a matter for experiment. Rollman has certainly criticized effectively one dubious analogy to TSD procedures which pain researchers have used. That is not the same as questioning the general usefulness of TSD models.

The Developmental Significance of Cross-Modal Matching

Philosophers and psychologists have sometimes argued that traditional distinctions between the spatial senses and, for that matter, between afferent sensory perception and efferent motor control are arbitrary and unhelpful (e.g., Bornstein, 1936; Freedman, 1968; von Hornbostel, 1927). Conceptual and experimental isolation of visual, auditory, and somesthetic processes (ultimately based upon Muller’s so-called “law of specific nervous energies”) led, undoubtedly, to a tremendous increase in knowledge of peripheral sensory physiology and to more or less detailed descriptions of sensory pathways to the central nervous system. Yet such work seemed to imply that human beings and other creatures see, hear, feel, and so on as isolated independent acts, as though individuals could only be known to each other as distinct independent visual, auditory, and sentient persons. Moreover ordinary language does not make the distinctions between modality dimensions which any treatment of, say, sight, hearing, and touch as isolated and distinct ways of knowing the world would seem to require. (Ordinary language is in fact shot through with synesthetic comparisons. See, e.g., Marks, 1975, for a recent discussion of synesthesia.) Of course, knowledge is perceptually based, but it is not obvious that it is visually based or (pace Berkeley) tactually based.

Sex and handedness as factors in visual-field organization for a categorization task

When right-handed males categorize faces presented in the right and left visual fields as male or female, a right visual-field advantage results. Subjects in the present study were divided on the basis of Annetts model according to sex and handedness, males and females, right-handers, nonfamilial left-handers, and familial left-handers. It was predicted that males would show a field advantage consistent with the cerebral hemisphere specialized for speech production (the left hemisphere in the case of right-handers and nonfamilial left-handers, and the right hemisphere in the case of familial left-handers). It was also predicted that females would be either weakly or inconsistently lateralized. A signal-detection paradigm in general confirmed these predictions. It was also shown that a subjects ability to change decisional criteria appropriately over trials was a function of visual field for both males and females. Decision making over time may therefore reveal a fundamental duality distinguishing the cerebral hemispheres in both sexes. Some of the implications of these results are discussed.

Algebraic models for integration of painful and nonpainful electric shocks

Subjects rated the average intensity of two sequentially presented electric shocks, which were either painful (intensity range from 1 to 4 mA, Experiment 1) or nonpainful (intensity range from .6 to .9 mA). In both experiments, stimuli were presented in a 4 by 4 factorial design to allow tests of algebraic models of the integration process under analysis of variance (Anderson, 1970, 1974). Both sets of data were fit by the equation Rij=w1s1+w2+s2, (w1+w2=1), where Rijis the rating scale response, s1 and s2 the scale values for the first and second stimuli, respectively, and w1 and w2 associated weights. When stimuli were painful, w1=w2, and when stimuli were nonpainful, w1< w2. Subjective scale values as a function of stimulus intensity appear to increase nonlinearly for painful stimuli and linearly for nonpainful stimuli. Some implications of the results for pain research are discussed.

Sex And Visual Field Effects on Accuracy and Decision Making When Subjects Classify Male and Female Faces

Male and female subjects classified tachistoscopically presented slide photographs of faces as male or female. In Experiments I and II presentation was at random to the right or left visual hemifield. Two different signal detection procedures demonstrated that accuracy for both visual fields is equivalent in females and that males show a marked right-field advantage. A third experiment showed that this field advantage is preserved for males when presentation right or left is by blocks of trials suggesting that the left hemisphere is specialized for classification tasks. Results also showed that optimization in signal detection tasks may be lateralized for both males and females though males optimize more poorly than females in the left visual field. The data are taken to demonstrate equipotentiality of hemispheric functioning in females and stronger hemispheric lateralization in males.

The Perception of Passive Joint-movements by Cerebral-palsied Children

Luces choice theory provided the psychophysical basis for investigating the ability of cerebral‐palsied children to detect passive movement of the elbow joint. The method included testing “yes” responses when the forearm was moved, and ‘false‐alarm’ responses of “yes” when no arm movement had occurred. The children were tested with their eyes closed.

Sex differences in cerebral lateralization in 3- and 4-year old children.

Following a procedure described by Jones [12, 13] boys and girls, 3 and 4 yr of age, were required to identify the sex of male and female faces tachistoscopically presented to the right and left visual fields. The results were in close conformity to those obtained with adults [12, 13]. Boys showed a strong and consistent right visual field advantage in accuracy. Girls showed no strong field advantage. It is argued cerebral lateralization remains constant across development. Theoretical issues relating to sex differences in cerebral lateralization are discussed.

Naming and discrimination of Chinese ideograms presented in the right and left visual fields

Abstract In a naming experiment Chinese subjects showed no significant visual field advantage for naming tachistoscopically presented Chinese characters. However, both Chinese and North American subjects tended to discriminate characters presented in the left visual field more accurately. The results are discussed in terms of the theories of hemispheric specialization.