Visual field differences in visual word recognition can emerge purely from perceptual learning: evidence from modeling Chinese character pronunciation

In Chinese orthography, a dominant character structure exists in which a semantic radical appears on the left and a phonetic radical on the right (SP characters); a minority opposite arrangement also exists (PS characters). As the number of phonetic radical types is much greater than semantic radical types, in SP characters the information is skewed to the right, whereas in PS characters it is skewed to the left. Through training a computational model for SP and PS character recognition that takes into account of the locations in which the characters appear in the visual field during learning, but does not assume any fundamental hemispheric processing difference, we show that visual field differences can emerge as a consequence of the fundamental structural differences in information between SP and PS characters, as opposed to the fundamental processing differences between the two hemispheres. This modeling result is also consistent with behavioral naming performance. This work provides strong evidence that perceptual learning, i.e., the information structure of word stimuli to which the readers have long been exposed, is one of the factors that accounts for hemispheric asymmetry effects in visual word recognition.     

Vocal Features of Conversational Sarcasm: A Comparison of Methods

This study investigated vocal cues that differentiate sarcastic utterances from non-sarcastic utterances. Utterances were drawn from videotapes of participant interviews and arranged on a master tape for analysis. Utterances that were identified as sarcastic by speakers and recognized as sarcastic by listeners were randomly arranged with utterances identified and recognized as non-sarcastic by the same participants. Both sarcastic and non-sarcastic utterances were analyzed by two methods–acoustic analysis and perceptual coding. The acoustic analysis proved slightly more successful than the perceptual coding in discriminating between sarcastic and non-sarcastic utterances. The acoustic analysis indicated that fundamental frequency, frequency range, length of utterance, and total amount of sound significantly discriminated sarcastic from non-sarcastic utterances. The perceptual coding method revealed that pitch range, length of utterance, and total amount of sound significantly discriminated sarcastic from non-sarcastic utterances. Moderate correlations were found between the acoustic and perceptual variables.     

Enhanced perceptual priming for neutral stimuli occurring in a traumatic context: two experimental investigations

Intrusive memories in posttraumatic stress disorder are often triggered by stimuli that are perceptually similar to those present shortly before or during the trauma. The present study aims to examine the possible role of perceptual priming in this phenomenon. It further investigates whether the degree of perceptual priming is associated with dissociation and whether both perceptual priming and intrusive memories can be reduced through elaboration. Two experiments measured perceptual priming for neutral stimuli that immediately preceded a "traumatic" event. Volunteers (N=46, 92) watched a series of "traumatic" and neutral picture stories, and completed a blurred object identification (perceptual priming) memory task, and a recognition memory task. Participants in Experiment 1 were selected to score either high or low on the Trait Dissociation Questionnaire [Murray, Ehlers, & Mayou (2002). Dissociation and posttraumatic stress disorder: Two prospective studies of motor vehicle accident survivors. British Journal of Psychiatry, 180, 363-368]. They also completed a state dissociation measure in the session. Experiment 2 randomly allocated participants to an experimental condition designed to increase elaboration or to a control condition. This experiment also included a measure of intrusive memories. Both experiments found enhanced perceptual priming for the stimuli that immediately preceded the "traumatic" stories compared to those preceding neutral stories. Participants with high trait dissociation showed relatively stronger perceptual perceptual priming. The degree of perceptual priming for stimuli from the "traumatic" stories also correlated with state dissociation (Experiment 1). Experimental manipulation of the elaboration of the stories showed that elaboration reduced the enhanced perceptual priming effect and the relative probability of reexperiencing symptoms (Experiment 2). The results support the role of perceptual priming in intrusions after traumatic events.     

Melioration and self-experimentation

Operant researchers rarely use the arena of applied psychology to motivate or to judge their research. Absence of tests by application weakens the field of basic operant research. Early in their development, the physical and biological sciences emphasized meliorative aspects of research. Improvement of human life was a major goal of these young sciences. This paper argues that if basic operant researchers analogously invoked a melioration criterion, the operant field might avoid its tendency toward ingrowth and instead generate a broadly influential science. Operant researchers could incorporate melioration by (a) creating animal models to study applied problems; (b) confronting questions raised by applied analysts and testing hypotheses in applied settings; or (c) performing self-experiments—that is, using experimental methods and behavioral techniques to study and change the experimenter's behavior.     

Across-persons versus within-persons tests of expectancy-value models: A methodological note

It has been asserted that (I) tests of expectancy-value models require within-persons analyses and that (2) within-persons analyses yield better predictions of behavioral tendencies than do across-persons analyses. The first assertion is correct; the second is not. Justification for within-persons tests of expectancy-value models must be made on theoretical rather than empirical grounds.     

Estimates of shape by eye, or, The little invariant that could

Five experiments were conducted to test the hypothesis that observers apprehend specific constancies under change in perspective. The constancies were projective properties of ellipses pictured to slant and tilt in depth. Observers were asked to reproduce the static upright view of a moving pair of ellipses, using a computer graphics display and interface. Projective invariants for pairs of conics were computed on the observers’ productions. A few experimental conditions revealed near-perfect performance. When pairs of coplanar ellipses were viewed under dynamic transformation in perspective, then invariants calculated on the observers’ productions were a match – in value on average – to the invariants of the transforming ellipse pairs. It is proposed that measures of projective properties afford a family of techniques that can be applied to gauge acuity for complex shapes in the study of visual form perception.     

Effects of combining disparate groups in the analysis of ethnic differences: Variations among asian american mental health service consumers in level of community functioning

The Asian American population comprises historically, socially, and culturally diverse ethnic groups. Given this diversity, investigators caution that combining disparate ethnic groups together may lead to erroneous conclusions. Whether by choice or necessity, however, mental health studies still typically consider Asian Americans as a single ethnic category rather than as separate ethnic groups. Few investigations have addressed the consequences of this practice. This paper examines the implications of conceptualizing Asian Americans as an ethnic category versus ethnic groups, in an investigation of the community functioning status of clients in publicly funded mental health programs in King County, Washington. When treated as a single ethnic category in a multivariate linear regression model, Asian Americans are found to have a lower level of functioning difficulty than their white counterparts. However, when treated as separate ethnic groups (e.g., Vietnamese, Japanese), only one of five Asian ethnic groups has a significantly lower level of difficulty. In a separate analysis of the Asian American subsample, groups are found to differ significantly from one another with respect to functional status. Several factors, including refugee status, account for this difference.     

Local rather than global processing of visual arrays in numerosity discrimination by pigeons (Columba livia)

A series of experiments investigated which stimulus properties pigeons use when they discriminate pairs of visual arrays that differ in numerosity. Transfer tests with novel stimuli confirmed that the birds’ choices were based on relative differences in numerosity. However, pigeons differed from other species in the non-numerical cues that affected their choices. In human and non-human primates, numerical discrimination is often influenced by continuous variables such as surface area or overall stimulus brightness. Pigeons showed little evidence of using those cues, even when summed area and brightness had been correlated with numerosity differences and reward outcome. But when array-element sizes were asymmetrically distributed across numerosities, the birds readily utilized information about item sizes as an additional discriminative cue. These novel results are discussed in relation to pigeons’ tendency to focus on local, rather than global dimensions when they process other non-numerical complex visual stimuli. The findings suggest there may be inter-specific differences in the type of perceptual information that provides the input stage for mechanisms underlying numerical processing. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Inattentional blindness for ignored words: Comparison of explicit and implicit memory tasks

Inattentional blindness is described as the failure to perceive a supra-threshold stimulus when attention is directed away from that stimulus. Based on performance on an explicit recognition memory test and concurrent functional imaging data Rees, Russell, Frith, and Driver [Rees, G., Russell, C., Frith, C. D., & Driver, J. (1999). Inattentional blindness versus inattentional amnesia for fixated but ignored words. Science, 286, 2504–2507] reported inattentional blindness for word stimuli that were fixated but ignored. The present study examined both explicit and implicit memory for fixated but ignored words using a selective-attention task in which overlapping picture/word stimuli were presented at fixation. No explicit awareness of the unattended words was apparent on a recognition memory test. Analysis of an implicit memory task, however, indicated that unattended words were perceived at a perceptual level. Thus, the selective-attention task did not result in perfect filtering as suggested by Rees et al. While there was no evidence of conscious perception, subjects were not blind to the implicit perceptual properties of fixated but ignored words.     

Perceptual interactions in a minimalist virtual environment

How in real-life or through the use of technical devices can we recognize the presence of other persons and under what conditions can we differentiate them from objects? In order to approach this question, in the study reported here we explored the most basic conditions necessary for participants to recognize the presence of another person during a perceptual interaction. We created a mini-network of two minimalist devices and investigated whether participants were able to differentiate the perception of another person from the perception of a fixed and a mobile object even when the pattern of sensory stimulation was reduced to a bare minimum. We show that participants can recognize when the all-or-none tactile stimulation they experienced was attributable to an encounter with the other participant's avatar or the mobile object rather than with a fixed object. Participants were also able to establish different strategies in order to favor the situations of mutual perception. Thus, in the minimalist conditions of our experiment, the perception of another intentional subject was not based purely on any particular shape or objective trajectories of displacement; it was also based on properties that are intrinsic to the joint perceptual activity itself.