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Cochlear implants (CIs) have enabled hundreds of thousands of profoundly hearing-impaired people to perceive sounds by electrically stimulating the auditory nerve. However, CI users are often very poor at locating sounds, which leads to impaired sound segregation and threat detection. We provided missing spatial hearing cues through haptic stimulation to augment the electrical CI signal. We found that this "electro-haptic" stimulation dramatically improved sound localisation. Furthermore, participants were able to effectively integrate spatial information transmitted through these two senses, performing better with combined audio and haptic stimulation than with either alone. Our haptic signal was presented to the wrists and could readily be delivered by a low-cost wearable device. This approach could provide a non-invasive means of improving outcomes for the vast majority of CI users who have only one implant, without the expense and risk of a second implantation. [ABSTRACT FROM AUTHOR]

The hypothesis that prey organisms can reduce the risk of predation by overtly signalling their unprofitability, or aposematism, has a long history in behavioural and evolutionary biology. To fully understand this longstanding idea, we need to measure and manipulate traits of aposematic prey, such as their distinctiveness from other prey, from the perspective of the potential predator. Specifically, we need measurements that are not anthropomorphic and that are based on the principles of discrimination developed by psychophysicists. This paper utilizes an experimentally tractable measure of discriminability based on signal detection theory as originally studied by psychophysicists. In addition, we develop and experimentally test a model to characterize the predator avoidance advantages derived from being distinct from other prey. By experimentally varying discriminability (and thus distinctiveness) we find that increased discriminability does confer a predator avoidance advantage, but the extent of this effect depends on the unprofitability of prey and the relative frequency of unprofitable prey. [ABSTRACT FROM AUTHOR]

The present study analysed the effects of floor impact noise on humans using both psychological and physiological methods. Floor impact noises caused by a standard impact source (i.e. impact ball) and five real impact sources (e.g., human footsteps and dropped objects) were recorded as sound stimuli. During the laboratory experiments, two factors that impact psychophysiological responses were considered: (1) types of impact sources (standard or real sources) and (2) the levels of floor impact noise ranging from 31.5 to 63 dBA in terms of A-weighted maximum sound pressure level ( L AFmax ). Twenty-one normal-hearing subjects were then asked to judge the noticeability and annoyance caused by the floor impact noises. Meanwhile, the subjects' physiological responses (heart rate: HR, electrodermal activity: EDA, and respiration rate: RR) were monitored throughout the experiments. Noise annoyance and noticeability increased with increases in noise levels, the impact ball resulted in higher noticeability and annoyance ratings than real sources. All physiological measures varied significantly with noise exposure; HR decreased, whereas EDA and RR increased. The results show that the physiological responses were not affected by the type of noise source. In addition, the noise level was found to be significantly related to EDA and RR changes, whereas the relationship between the noise level and HR was not found to be significant. [ABSTRACT FROM AUTHOR]

Situation awareness and workload are popular constructs in human factors science. It has been hotly debated whether these constructs are scientifically credible, or whether they should merely be seen as folk models. Reflecting on the works of psychophysicist Stanley Smith Stevens and of measurement theorist David Hand, we suggest a resolution to this debate, namely that human factors constructs are situated towards the operational end of a representational-operational continuum. From an operational perspective, human factors constructs do not reflect an empirical reality, but they aim to predict. For operationalism to be successful, however, it is important to have suitable measurement procedures available. To explore how human factors constructs are measured, we focused on (mental) workload and its measurement by questionnaires and applied a culturomic analysis to investigate secular trends in word use. The results reveal an explosive use of the NASA Task Load Index (TLX). Other questionnaires, such as the Cooper Harper rating scale and the Subjective Workload Assessment Technique, show a modest increase, whereas many others appear short lived. We found no indication that the TLX is improved by iterative self-correction towards optimal validity, and we argue that usage of the NASA-TLX has become dominant through a Matthew effect. Recommendations for improving the quality of human factors research are provided. [ABSTRACT FROM AUTHOR]

Statistical modeling produces compressed and often more easily interpretable descriptions of experimental data in form of model parameters. When experimental manipulations target selected parameters, it is necessary for their interpretation that other model components remain constant. For example, psychophysicists use dose rate models to describe how behavior changes as a function of a single stimulus variable. The main interest is on shifts of this function induced by experimental manipulation, assuming invariance in other aspects of the function. Combining several experimental conditions in a joint analysis that takes such invariance constraints into account can result in a complex model for which no robust standard procedures are available. We formulate a solution for the joint analysis through repeated applications of standard procedures by allowing an additional assumption. This way, experimental conditions can be analyzed separately such that all conditions are implicitly taken into account. We investigate the validity of the supplementary assumption through simulations. Furthermore, we present a natural way to check whether a joint treatment is appropriate. We illustrate the method for the specific case of the psychometric function; however the procedure applies to other models that encompass multiple experimental conditions. [ABSTRACT FROM AUTHOR]

Pitch, our perception of how high or low a sound is on a musical scale, is a fundamental perceptual attribute of sounds and is important for both music and speech. After more than a century of research, the exact mechanisms used by the auditory system to extract pitch are still being debated. Theoretically, pitch can be computed using either spectral or temporal acoustic features of a sound. We have investigated how cues derived from the temporal envelope and spectrum of an acoustic signal are used for pitch extraction in the common marmoset (Callithrix jacchus), a vocal primate species, by measuring pitch discrimination behaviorally and examining pitch-selective neuronal responses in auditory cortex. We find that pitch is extracted by marmosets using temporal envelope cues for lower pitch sounds composed of higher-order harmonics, whereas spectral cues are used for higher pitch sounds with lower-order harmonics. Our data support dual-pitch processing mechanisms, originally proposed by psychophysicists based on human studies, whereby pitch is extracted using a combination of temporal envelope and spectral cues. [ABSTRACT FROM AUTHOR]

Starting from the investigations of Sechenov, Pavlov, and Uchtomsky, the Russian psychophysiological school has been considering adaptation in connection with the biological and social origin of the person (human as a rational being) as an integrated, coordinated, and self-controlled system. On the basis of the problem of man and the environment, Medvedev added to the theory of human adaptation the activity paradigm that enables us to uncover the distinctive features of occupational activities under various environment conditions. The theoretical and practical investigations based on the activity methodology presented the opportunity to find new principles of interaction between man and the environment and of the strategy of adaptive behavior. From the investigations one could see that the main characteristic of the human-environment interaction is that the active factor is the human who could simulate different adaptation strategies. [ABSTRACT FROM AUTHOR]

Studies by cognitive psychologists, psychophysicists, neuroscientists, and economists provide ample evidence that humans use prior knowledge to bias decisions adaptively. In this study, we sought to locate and investigate the brain areas mediating this behavior. Participants viewed ambiguous abstract shapes and decided whether a shape was of Category A (smoother) or B (bumpier). The decision was made in the context of one of two prior knowledge cues, 80/20 and 50/50. The 80/20 cue indicated that upcoming shapes had an 80% probability of being of one category, for example, B, and a 20% probability of being of the other. The 50/50 cue indicated that upcoming shapes had an equal probability of being of either category. The shift in bias produced by the 80/20 cue relative to the 50/50 cue was of the predicted sign for every subject but varied in magnitude. We searched for brain regions in which activity changes correlated with the extent of the bias shift; these were dorsolateral pFC (middle frontal gyrus), inferior frontal junction, anterior insula, inferior parietal lobule, intraparietal sulcus, head of the caudate, posterior cingulate cortex, and fusiform gyrus. The findings indicate that an individual's brain activity in these regions reflects the extent to which that individual makes use of prior knowledge to bias decisions. We also created within-ROI tuning curves by binning the shape curvature levels and plotting brain activity levels at each of the nine bins. In the fronto-parietal and anterior insula ROIs, the tuning curves peaked at targets contraindicated by the prior knowledge cue (e.g., Category B targets if the 80/20 cue meant 20% probability B). The increased activity in these regions likely indicates a no-go response when sufficient perceptual evidence favored the alternative contraindicated by the 80/20 cue. [ABSTRACT FROM AUTHOR]

Abstract: A large and growing body of evidence from marketing and behavioral economics suggests consumer preferences are not fixed but instead depend on the choice set. Although the idea that context alters perception is not new to psychophysicists or sensory scientists, we suggest that asymmetric dominance may represent a novel and potentially important source of bias in hedonic product testing and food choice research. In a series of six experiments using model systems, commercially available beverages and solid foods, we explored the possibility that asymmetric dominance effects may influence the results of food preference testing. Within a model system (experiments 1–3), we failed to observe evidence of a bias arising from asymmetric dominance. In contrast, when perceptually complex beverages and foods were used (experiments 4–6), we found relative preference was altered by the introduction of an additional product into the choice set. Critically, we found this bias was able to induce a significant preference (experiments 4–5) or make a significant preference disappear (experiment 6). Implications of this potential source of bias are discussed in a context relevant to sensory scientists and product developers. [Copyright &y& Elsevier]

This paper explores the dynamics of mutual idealization within the analytic dyad. While the subject of idealization is not a new one, very little has been written about the analyst's own participation in patients' idealizations or her vulnerability to idealizing the patient. I use both published and unpublished materials to muse about coconstructed idealizations as they appear to have coalesced in Winnicott's treatment of Masud Khan and Harry Guntrip. Because the notion that we might be involved in being idealized by our patients-or in idealizing them-collides with our professional vision, we tend to be highly resistant to acknowledging these dynamics and often turn to denigration when they are unmasked. I argue for the ubiquity of idealization's dynamics and against the demonization of Winnicott. [ABSTRACT FROM AUTHOR]

Historians acknowledge Euclid and Fechner, respectively, as the founders of classical geometry and classical psychophysics. At all times, their ideas have been reference points and have shared the same destiny of being criticized, corrected, and even radically rejected, in their theoretical and methodological aspects and in their epistemological value. According to a model of measurement of magnitudes which goes back to Euclid, Fechner () developed a theory for psychical magnitudes that opened a lively debate among numerous scholars. Fechner's attempt to apply the model proposed by Euclid to subjective sensation magnitudes-and the debate that followed-generated ideas and concepts that were destined to have rich developments in the psychological and (more generally) scientific field of the twentieth century and that still animate current psychophysics. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article discusses insights to be gleaned from the diary of German experimental psychologist Gustav Theodor Fechner concerning his development of the scientific field of psychophysics. Emphasis is given to Fechner's writing on the development of his book "Elements of Psychophysics." Fechner's interest in the work of German experimental psychologist Wilhelm Wundt is discussed, along with the publication of his work "The Day-View Opposed to the Night-View" (German: "Die Tagesansicht gegenüber der Nachtansicht").

Abstract: The eminent psychophysicist, S.S. Stevens, once remarked that, “the basic problem of psychology was the definition of the stimulus” (, p. 46). By expanding the traditional definition of the stimulus, the study of animal learning has metamorphosed into animal cognition. The main impetus for that change was the recognition that it is often necessary to postulate a representation between the traditional S and R of learning theory. Representations allow a subject to represent a stimulus it learned previously that is currently absent. Thus, in delayed matching-to-sample, one has to assume that a subject responds to a representation of the sample during test if it responds correctly. Other examples, to name but a few, include concept formation, spatial memory, serial memory, learning a numerical rule, imitation and metacognition. Whereas a representation used to be regarded as a mentalistic phenomenon that was unworthy of scientific inquiry, it can now be operationally defined. To accommodate representations, the traditional discriminative stimulus has to be expanded to allow for the role of representations. The resulting composite can account for a significantly larger portion of the variance of performance measures than the exteroceptive stimulus could by itself. [Copyright &y& Elsevier]

The issue of the relation of eye position to perceptual reversals of the ambiguous figure of the‘Necker cube’ dates back to Necker's original article[L.A. Necker (1832)The London&Edinburgh Philosophical Magazine and Journal of Science,1, 329–337]. Despite the investigations of many distinguished psychophysicists since then, the question of whether perceptual switching is a cause or a consequence of associated changes in eye position has remained a matter of debate. In the present study we overcame methodological problems that have bedevilled many previous studies. We avoided any instruction that could interfere with the human subjects' free viewing of the Necker cube, tracked the eye position precisely and used biased versions of the cube that produced unambiguous percepts to determine how each subject actually looked at the cube. We show that, under these free-viewing conditions, there is a close link between the perception of the Necker cube and eye position. The average eye position of most subjects is at an extreme value at about the time when the subject's perception switches. From the biased cube trials we can infer that the polarity of the extreme corresponds to the percept which the subject had before the switch. These data indicate a bidirectional coupling between eye position and perceptual switching so that, after a subject's perceptual state changes, their eye position shifts to view the newly established percept. When the eye position approaches the corresponding extreme, the percept, in turn, becomes more and more likely to switch. This result suggests that the changed eye position itself might provide a negative feedback signal that suppresses the percept. [ABSTRACT FROM AUTHOR]

Abstract Until a few years ago, visual search tasks were of exclusive pertinence to psychophysicists and cognitive psychologists trying to understand the operating principles and computational constraints of visual perception and visual selective attention. In recent years, cognitive neuroscience, with its powerful tools, has started to explore more directly the neuronal mechanisms underlying search performance in humans and macaques, aiming at the same general goals. New observations from a number of cognitive neuroscience approaches are promising a near future of great excitement in this field of research. This article offers a critical review of some of these recent contributions and highlights some of the interpretational problems that they pose. [ABSTRACT FROM AUTHOR]

Summary A research paradigm for the study of human experience is presented which is comprised of two stages. The first, an experiential approach, begins with a mode of phenomenological analysis in which investigators question and passively attend to their experiences of a particular phenomenon of experience such as anger or anxiety. They describe these experiences m the context of placing themselves m situations or reliving past situations. The experiences are then described m terms of how they experience the phenomenon rather than in terms of the target of their attention or the stimulus conditions. From analysis of these descriptions, it is possible to formulate definitional hypotheses, that is, statements about the necessary and sufficient experiential elements for the occurrence of a given phenomenon. It also is possible to formulate functional hypotheses, statements about the relationships between these experiential elements. Both definitional and functional hypotheses can then be tested in experiments using subjects that are unfamiliar with these hypotheses. Such experiments constitute the quantitative methods stage of this research paradigm. Definitional hypotheses can be tested with questionnaires and functional hypotheses can be tested using ratio scaling techniques similar to those employed by psychophysicists. Since the variables of functional hypotheses remain within the domain of the experiencing person, in may be possible to discover laws of experience. Finally, confirmation of experiential hypotheses through direct experiential involvement in the approach phase and testing their reliability and generalizability in the methods phase represent two stages of verification that are epistemologically complementary. [ABSTRACT FROM AUTHOR]

Social scientists are alerted to the fact that psychophysicists have reliably measured utility with direct introspective techniques. Utility is a power function of money with an exponent of approximately 0.43, indicating decreasing marginal utility. Discussion on some methodological issues including the measurability controversy is offered. The main benefit of a cardinally measurable utility is that in principle the economic approach is now empirically accessible and therefore falsifiable. [ABSTRACT FROM AUTHOR]

The article profiles professor and psychophysicist Linda Bartoshuk and her research on so-called supertasters, or people with uncommonly high taste sensitivity. Bartoshuk is said to be a leader in research on subjective experience, a one-time research taboo. Bartoshuk's risk-taking resulted in notable publications, election to the National Academy of Sciences, and her position as the president of the Association for Psychological Science (APS). Bartoshuk is said to be studying the subjective scales used by psychologists as a basis for their work.

Describes the above-named upcoming conference event. May include topics to be covered or calls for papers. [ABSTRACT FROM AUTHOR]

Wavefront technology and wavefront-based vision correction are major advances but will not, in isolation, achieve the goal of perfect vision. Study of the animal kingdom teaches lessons of adaptation, leading to the conclusion that the human visual system is probably optimized for our ancestral hunter-gatherers, but today's visual demands have developed faster than the pace of evolution. Psychophysical studies of perception emphasize the importance of the visual processing system in the totality of visual function, with application today in areas such as multifocal intraocular lenses. The goal of “perfect vision” is more than optimized optics. A better understanding of visual function can be achieved only by a cooperative effort of ophthalmologists, vision scientists, and psychophysicists. [Copyright &y& Elsevier]