Orthographic error monitoring in old age: lexical and sublexical availability during perception and production

Previous research suggests that older adults suffer declines in producing accurate spellings but retain the ability to accurately detect misspellings. The preservation of perception in the face of impaired production has been used to support a model of aging in which age impairs access to linguistic representations under specific circumstances, while representations themselves remain intact. The current research tests two predictions of this Transmission Deficit Hypothesis (TDH): first, that the differential effect of age on perception and production occurs when tasks are equated on response requirements and underlying representations, and second, that both word and spelling frequency interact to determine the effect of age on performance. Results of two error monitoring tasks supported the predictions of the TDH, demonstrating age-related production impairments that interacted with both word and spelling frequency, but no impairment of older adults' spelling perception, even for low frequency words or spellings.     

Characterizing the influence of native language experience on adult speech perception.

Previous cross-language research has indicated that some speech contrasts present greater perceptual difficulty for adult non-native listeners than others do. It has been hypothesized that phonemic, phonetic, and acoustic factors contribute to this variability. Two experiments were conducted to evaluate systematically the role of phonemic status and phonetic familiarity in the perception of non-native speech contrasts and to test predictions derived from a model proposed by Best, McRoberts, and Sithole (1988). Experiment 1 showed that perception of an unfamiliar phonetic contrast was not less difficult for subjects who had experience with an analogous phonemic distinction in their native language than for subjects without such analogous experience. These results suggest that substantive phonetic experience influences the perception of non-native contrasts, and thus should contribute to a conceptualization of native language-processing skills. In Experiment 2, English listeners' perception of two related nonphonemic place contrasts was not consistently different as had been expected on the basis of phonetic familiarity. A clear order effect in the perceptual data suggests that interactions between different perceptual assimilation patterns or acoustic properties of the two contrasts, or interactions involving both of these factors, underlie the perception of the two contrasts in this experiment. It was concluded that both phonetic familiarity and acoustic factors are potentially important to the explanation of variability in perception of nonphonemic contrasts. The explanation of how linguistic experience shapes speech perception will require characterizing the relative contribution of these factors, as well as other factors, including individual differences and variables that influence a listener's orientation to speech stimuli.     

Characterizing the influence of native language experience on adult speech perception

Previous cross-language research has indicated that some speech contrasts present greater perceptual difficulty for adult non-native listeners than others do. It has been hypothesized that phonemic, phonetic, and acoustic factors contribute to this variability. Two experiments were conducted to evaluate systematically the role of phonemic status and phonetic familiarity in the perception of non-native speech contrasts and to test predictions derived from a model proposed by Best, McRoberts, and Sithole (1988). Experiment 1 showed that perception of an unfamiliar phonetic contrast was not less difficult for subjects who had experience with an analogous phonemic distinction in their native language than for subjects without such analogous experience. These results suggest that substantive phonetic experience influences the perception of non-native contrasts, and thus should contribute to a conceptualization of native language-processing skills. In Experiment 2, English listeners’ perception of two related nonphonemic place contrasts was not consistently different as had been expected on the basis of phonetic familiarity. A clear order effect in the perceptual data suggests that interactions between different perceptual assimilation patterns or acoustic properties of the two contrasts, or interactions involving both of these factors, underlie the perception of the two contrasts in this experiment. It was concluded that both phonetic familiarity and acoustic factors are potentially important to the explanation of variability in perception of nonphonemic contrasts. The explanation of how linguistic experience shapes speech perception will require characterizing the relative contribution of these factors, as well as other factors, including individual differences and variables that influence a listener’s orientation to speech stimuli.     

Altered emotional and motivational processing in the transgenic rat model for Huntington's disease

Huntington disease (HD) is caused by an expansion of CAG repeat in the Huntingtin gene. Patients demonstrate a triad of motor, cognitive and psychiatric symptoms. A transgenic rat model (tgHD rats) carrying 51 CAG repeats demonstrate progressive striatal degeneration and polyglutamine aggregates in limbic structures. In this model, emotional function has only been investigated through anxiety studies. Our aim was to extend knowledge on emotional and motivational function in symptomatic tgHD rats. We subjected tgHD and wild-type rats to behavioral protocols testing motor, emotional, and motivational abilities. From 11 to 15 months of age, animals were tested in emotional perception of sucrose using taste reactivity, acquisition, extinction, and re-acquisition of discriminative Pavlovian fear conditioning as well as reactivity to changes in reinforcement values in a runway Pavlovian approach task. Motor tests detected the symptomatic status of tgHD animals from 11 months of age. In comparison to wild types, transgenic animals exhibited emotional blunting of hedonic perception for intermediate sucrose concentration. Moreover, we found emotional alterations with better learning and re-acquisition of discriminative fear conditioning due to a higher level of conditioned fear to aversive stimuli, and hyper-reactivity to a negative hedonic shift in reinforcement value interpreted in term of greater frustration. Neuropathological assessment in the same animals showed a selective shrinkage of the central nucleus of the amygdala. Our results showing emotional blunting and hypersensitivity to negative emotional situations in symptomatic tgHD animals extend the face validity of this model regarding neuropsychiatric symptoms as seen in manifest HD patients, and suggest that some of these symptoms may be related to amygdala dysfunction.     

A PARADOX IN THE PERCEPTION OF LUMINANCE GRADIENTS. III

In the second paper of this series (Bergström, 1967) a psychophysical model of certain contrast phenomena in the perception of luminance gradients was outlined on the basis of empirical findings. From this model two predictions were derived about the appearance of a steplike luminance distribution. These predictions about relations between the brightness of different parts of the distribution have been tested by means of a ranking method and a matching technique. Both predictions were confirmed.     

Lateral interception I: operative optical variables, attunement, and calibration

J. J. Gibson (1966, 1979) suggested that improvement in perception and action can be attributed in part to changes in which variable is attended to. Such reattunement has been demonstrated with observers making judgments in response to simulations. The present study sought attunement changes in the perception of real events and in visually guided action. In 3 experiments, adults judged the passing distance of or attempted to catch balls. Discrete measures and the predictions of a modified required velocity model (e.g., R. J. Bootsma, V. Fayt, F. T. J. M. Zaal, & M. Laurent, 1997) were used to reveal which variables were exploited. Participants differed from each other and, to some extent, changed in the optical variables used, in catching as well as judging. Nevertheless, the changes were much smaller than in previous simulation-judgment studies; calibration was also found to underlie the improvements in performance.     

Bilateral symmetry in coincident timing: a preliminary investigation

The purpose of this study was to investigate the coincident timing accuracy of the preferred and nonpreferred limbs in a ballistic striking task. A secondary purpose was to examine subjects' perception of their performance proficiency with each limb. 30 right-hand preferred subjects performed a 60-cm horizontal arm motion to displace a wooden barrier in coincidence with the final light in a series that traveled down a runway. Interestingly, while both the preferred and nonpreferred limbs were equally proficient in temporal accuracy, 80% of subjects perceived a bilateral asymmetry in performance. The influence of this perception on bilateral skill performance and acquisition remains in question.     

Testing the BIAS Map Model: The Positive Effects of Perceiving Weakness and Harmony in Powerful Out-Groups

ABSTRACT

Two experimental studies were used to test predictions derived from the BIAS map model. While the first experiment manipulated the perception of power in the out-group (the USA), the second manipulated the perceived harmony of the relationships between this out-group and the participants' own national group. The results confirmed the hypotheses derived from the model. The manipulation of power affected the perception of competence, thus affecting emotions and behavioral dispositions towards out-group members. The manipulation of perceived harmony of intergroup interests had a similar effect, but was not mediated by changes in the attribution of competence, but of warmth. Attitudes did not play a significant role in the prediction of emotions and behavioral intentions.     

Some additional predictions and further tests of the Marr-Ullman model of motion perception

The Marr-Ullman model for motion detection in the human visual system functions by means of the dual input of polarity-specific edge detectors and luminance change detectors. Moulden and Begg (1986) found a polarity-specific motion aftereffect which they claimed provided support for this dual input model. The logic of their experiment is examined, and it is shown that several additional predictions arise from the Marr-Ullman model, which were not supported by Moulden and Begg's study. A more powerful experiment was carried out and these additional predictions were disconfirmed, although the polarity-specific effect did emerge. A consideration of alternative explanations of this effect led to a second experiment in which an attempt was made to discover the actual determinants of the effect. This revealed that polarity-specific units are unlikely to play any part in the phenomenon. It was concluded, in the light of this and other evidence, that one of a class of alternative models is more likely to be the actual mechanism for motion perception. However, careful consideration of the Marr-Ullman model indicated that it may be untestable in principle if various differentially weighted levels of neural integration are envisaged.     

Stereo-motion cooperation and the use ofmotion disparity in the visual perception of 3-D structure

When an observer views a moving scene binocularly, both motion parallax and binocular disparity provide depth information. In Experiments lA-1C, we measured sensitivity to surface curvature when these depth cues were available either individually or simultaneously. When the depth cues yielded comparable sensitivity to surface curvature, we found that curvature detection was easier with the cues present simultaneously, rather than individually. For 2 of the 6 subjects, this effect was stronger when the component of frontal translation of the surface was vertical, rather than horizontal. No such anisotropy was found for the 4 other subjects. If a moving object is observed binocularly, the patterns of optic flow are different on the left and right retinae. We have suggested elsewhere (Cornilleau-Pérès & Droulez, in press) that this motion disparity might be used as avisual cue for the perception of a 3-D structure. Our model consisted in deriving binocular disparity from the left and right distributions of vertical velocities, rather than from luminous intensities, as has been done in classical studies on stereoscopic vision. The model led to some predictions concerning the detection of surface curvature from motion disparity in the presence or absence of intensity-based disparity (classically termedbinocular disparity). In a second set of experiments, we attempted to test these predictions, and we failed to validate our theoretical scheme from a physiological point of view.     

An evaluation of psychophysical models of auditory change perception

In many psychophysical experiments, the participant's task is to detect small changes along a given stimulus dimension or to identify the direction (e.g., upward vs. downward) of such changes. The results of these experiments are traditionally analyzed with a constant-variance Gaussian (CVG) model or a high-threshold (HT) model. Here, the authors demonstrate that for changes along three basic sound dimensions (frequency, intensity, and amplitude-modulation rate), such models cannot account for the observed relationship between detection thresholds and direction-identification thresholds. It is shown that two alternative models can account for this relationship. One of them is based on the idea of sensory quanta; the other assumes that small changes are detected on the basis of Poisson processes with low means. The predictions of these two models are then compared against receiver operating characteristics (ROCs) for the detection of changes in sound intensity. It is concluded that human listeners' perception of small and unidimensional acoustic changes is better described by a discrete-state Poisson model than by the more commonly used CVG model or by the less favored HT and quantum models.     

Simple predictions fueled by capacity limitations: when are they successful?

Counterintuitively, Y. Kareev, I. Lieberman, and M. Lev (1997) found that a lower short-term memory capacity benefits performance on a correlation detection task. They assumed that people with low short-term memory capacity (low spans) perceived the correlations as more extreme because they relied on smaller samples, which are known to exaggerate correlations. The authors consider, as an alternative hypothesis, that low spans do not perceive exaggerated correlations but make simpler predictions. Modeling both hypotheses in ACT-R demonstrates that simpler predictions impair performance if the environment changes, whereas a more exaggerated perception of correlation is advantageous to detect a change. Congruent with differences in the way participants make predictions, 2 experiments revealed a low capacity advantage before the environment changes but a high capacity advantage afterward, although this pattern of results surprisingly only existed for men.     

The kinematics of locomotion toward a goal

A mathematical model is developed that treats rats in runways as uniformly accelerated bodies. The purpose of the model is to permit conversion of the continuously varying measures of runway speeds at different points in the alley into three invariant parameters of performance: start latency, acceleration, and brakepoint. This simple model fits most of the data examined, and changes in the parameters throw new light on phenomena such as the partial reinforcement acquisition effect. In particular, it is shown that partially reinforced rats accelerate faster but cease accelerating earlier in the runway than do continuously reinforced rats. This explains the qualitative differences often found between start and goal speed measures. The analysis takes as its unit patterns of terminal behavior rather than the rate of the responses that constitutes them, and thus may permit coherent treatment of instrumental and operant behavior.     

消费者不道德行为与员工情绪衰竭关系的调节性中介模型

大量研究业已揭示,消费者针对员工的不道德行为是导致员工情绪衰竭的重要因素,但是对于消费者不针对员工的不道德行为（consumer unethical behavior that are not employee directed,CUB）是否会影响员工的情绪衰竭,研究还较少涉及。基于道义伦理学,本研究提出了一个调节性中介模型,以分析CUB与员工情绪衰竭的关系。该模型假定,CUB与员工情绪衰竭之间的关系以情绪抑制为中介,并且受到员工道德认同的调节。对198名销售人员的研究发现,即使控制了消费者针对员工的不道德行为,CUB仍影响着员工的情绪衰竭;CUB与员工情绪衰竭的关系受到道德认同的调节,道德认同较高的员工表现出较高程度的情绪抑制与情绪衰竭。研究支持了假设的调节性中介模型,情绪抑制在CUB和情绪衰竭之间发挥着部分中介作用,不仅如此,这一中介作用还受到道德认同的调节,情绪抑制在CUB和情绪衰竭之间的间接效应主要表现在道德认同较高的员工中。最后探讨了研究发现的理论意义、不足及未来发展方向。     

TWO-DIMENSIONAL FIELD EFFECTS AND STATIC SLANT PERCEPTION

E riksson , E. S. Two-dimensional field effects and static slant perception. Scand. J. Psychol ., 1968, 9, 19–32.—The model for two-dimensional field effects as developed in a previous article makes possible certain predictions concerning perceived shape which, taken together with the subjective slant principle, result in predictions of the perceived slant of a circle or a surface composed of circles. Data were obtained which agreed with these predictions, showing that the geometrical shape slant invariance hypothesis is an inadequate model for depth perception. Some implications for gradient theory, Helmholtzian theories and Gestalt theory are discussed.     

Testing between the TRACE model and the fuzzy logical model of speech perception

The TRACE model of speech perception (McClelland & Elman, 1986) is contrasted with a fuzzy logical model of perception (FLMP) (Oden & Massaro, 1978). The central question is how the models account for the influence of multiple sources of information on perceptual judgment. Although the two models can make somewhat similar predictions, the assumptions underlying the models are fundamentally different. The TRACE model is built around the concept of interactive activation, whereas the FLMP is structured in terms of the integration of independent sources of information. The models are tested against test results of an experiment involving the independent manipulation of bottom-up and top-down sources of information. Using a signal detection framework, sensitivity and bias measures of performance can be computed. The TRACE model predicts that top-down influences from the word level influence sensitivity at the phoneme level, whereas the FLMP does not. The empirical results of a study involving the influence of phonological context and segmental information on the perceptual recognition of a speech segment are best described without any assumed changes in sensitivity. To date, not only is a mechanism of interactive activation not necessary to describe speech perception, it is shown to be wrong when instantiated in the TRACE model.     

The self-attention-induced feedback loop and social facilitation

It has been proposed that self-directed attention leads to the engagement of a cybernetic feedback loop, by which discrepancies between present behavior and a standard of comparison are reduced. This analysis is applied to performance facilitation effects, which are more typically explained in terms of drive theories. Though these two approaches to motivation make similar behavioral predictions in this context, they assume different mediating states. Support is noted for the assumptions that mirror presence and audience presence induce self-focus, and that they lead to comparison with salient behavioral standards. Support for the assumption that these manipulations increase arousal is also reviewed, and is challenged on methodological grounds. The attentional analysis is used to derive predictions regarding changes in physiological state over the course of a typical social facilitation procedure. An experiment is reported which confirmed these predictions. Discussion centers on how to interpret physiological changes in terms that are compatible with control theory, how to account for social impairment phenomena in terms of the present model, and the conceptual relationship between mirror presence and audience presence as experimental manipulations.     

An analysis of letter expertise in a levels-of-categorization framework

While there has been increasing effort in dissociating the neural substrates recruited by perception of different objects, the theoretical and behavioural work needed to understand such dissociation lags behind. In an attempt to compare expertise in letter and face perception, we outline a theoretical framework that characterizes different types of object expertise based on the task demand (level of abstraction) required in object categorization. Face perception requires categorization at a subordinate level, whereas letter perception involves mainly basic-level categorization. Accordingly face and letter perception should represent two different types of expertise and display different neural and behavioural markers. Results from three behavioural experiments supported the predictions of the framework in that letter expertise is characterized by an enhancement of the basic-level advantage, instead of its attenuation as typically found for face perception. We compare this framework with Farah's taxonomy of visual abilities based on cooccurrence of deficits in visual agnosias.