Perceptual restoration of missing sounds in a group of hallucinating schizophrenics.

17 subjects diagnosed with schizophrenia and having auditory hallucinations in their case history were compared with 15 control subjects in an experiment on perceptual restoration. A tone pattern was presented, then interrupted by noise, under conditions such that the tone pattern could be heard as going on continuously (restoration). A series of 16 stimuli with a distractor of varying amplitude (noise) were presented. Healthy controls reliably reported restoration in Presentations 9 and 10. Four schizophrenics reported no restoration at all. Three of them reported restoration earlier than controls, and four others reported it later than controls and continued to report the phenomenon after a point at which no healthy controls did. Six other presented an irregular pattern of response to the phenomenon. The results are discussed with respect to the neurophysiological functioning of the auditory pathway and schizophrenic symptoms.     

Perceptual restoration in toddlers

Perception by adults is a constant interaction between the top-down effects of prior knowledge and the effects of bottom-up perceptual information. One obvious example of this interaction is the perceptual restoration effect, in which adult listeners have the illusion that a word is complete when a portion of it has been replaced by a masking noise. In four experiments, we demonstrate that toddlers fail to show the illusion of perceptual restoration, even in constrained situations with words they know quite well. Not only do toddlers have less prior knowledge than do adults, but they also appear to place less reliance on the knowledge that they do have, at least in the paradigm tested here. Instead, toddlers appear to be more tied to the perceptual information they receive than are adults.     

Perceptual comparisons with laterally presented pictures and environmental sounds

Two experiments studied perceptual comparisons with cues that vary in one of four ways (picture, sound, spoken word, or printed word) and with targets that are either pictures or environmental sounds. The basic question probed whether modality or differences in format were factors that would influence picture and sound perception. Also of interest were cue effect differences when targets are presented on either the right or left side. Students responded to a same-different reaction time task that entailed matching cue-target pairs to determine whether the successive stimulus events represented features drawn from the same basic item. Cue type influenced reaction times to pictures and environmental sounds, but the effects were qualified by response type and with picture targets by presentation side. These results provide some additional evidence of processing asymmetry when pictures are directed to either the right or left hemisphere, as well as for some asymmetries in cross-modality cuing. Implications of these findings for theories of multisensory processing and models of object recognition are discussed.     

Perceptual sensitivity to spectral properties of earlier sounds during speech categorization

Attention, Perception, & Psychophysics - Speech perception is heavily influenced by surrounding sounds. When spectral properties differ between earlier (context) and later (target) sounds, this...     

知觉经验与知觉内容

知觉(perception)是指我们通过视觉、听觉、触觉、嗅觉、味觉等感觉器官而获得的对事物以及外部世界的意识感知.知觉经验(perceptual experience)的一个显著的特点是它具有某种现象特征,即知觉者会体验到一种"那究竟像什么(what it is like)"的感觉.例如,一个人会从红色视觉经验中体验到"红色究竟像什么"的意识感受性(qualia).知觉内容(perceptual content)粗略地讲是指通过知觉经验向知觉者所传递的信息.关于知觉问题在哲学上的重要性,我们可以从以下几点来看:在形而上学方面,知觉是我们了解外部物理世界究竟存在什么的主要手段;在认识论方面,研究知觉是研究我们如何达到关于外部物理世界的知识的主要手段;在语言哲学方面,知觉内容是我们的心灵与外部物理世界的关联及互动在语言实践上的体现;在心灵哲学方面,知觉经验中的现象特征与意识及意向性之间存在着深层的内在联系.     

Categorization of sounds

The authors conducted 4 experiments to test the decision-bound, prototype, and distribution theories for the categorization of sounds. They used as stimuli sounds varying in either resonance frequency or duration. They created different experimental conditions by varying the variance and overlap of 2 stimulus distributions used in a training phase and varying the size of the stimulus continuum used in the subsequent test phase. When resonance frequency was the stimulus dimension, the pattern of categorization-function slopes was in accordance with the decision-bound theory. When duration was the stimulus dimension, however, the slope pattern gave partial support for the decision-bound and distribution theories. The authors introduce a new categorization model combining aspects of decision-bound and distribution theories that gives a superior account of the slope patterns across the 2 stimulus dimensions.     

Perceptual precision

The standard view in philosophy of mind is that the way to understand the difference between perception and misperception is in terms of accuracy. On this view, perception is accurate while misperception is inaccurate. However, there is some evidence (albeit controversial evidence) that perceptual experience actually involves widespread inaccuracy. I add to that evidence in the paper. Then I point toward a way of understanding the difference between perception and misperception, not in terms of accuracy alone, but in terms of precision. That is, I argue that perceptual experience is designed to enable more fine-grained discrimination among the properties that are most useful for action, even if that involves inaccuracy. The view in this paper motivates a new account of illusion, on which illusions are imprecise as well as inaccurate. I call this the Precision Account of Illusion.     

Perceptual Intuitionism

In the recent metaethical literature there has been significant interest in the prospects for what I am denoting ‘Perceptual Intuitionism’: the view that normal ethical agents can and do have non‐inferential justification for first‐order ethical beliefs by having ethical perceptual experiences, e.g., Cullison 2010, McBrayer 2010, Vayrynen 2008. If true, it promises to constitute an independent a posteriori intuitionist epistemology, providing an alternative to intuitionist accounts which posit a priori intuition and/or emotion as sources of non‐inferentially justified ethical beliefs. As it is formulated, it is plausible that a necessary condition for the view is the truth of Ethical Perception: normal ethical agents can and do have perceptual experiences (at least some of which are veridical) as of the instantiation of ethical properties. In this paper a sophisticated and promising account of Ethical Perception is offered. Extant objections are shown to fail. However, it will be argued that it is far from obvious that the account of Perceptual Intuitionism which emerges constitutes an independent alternative to other intuitionist accounts. This is because we have reason to think that ethical perceptual experience may be epistemically dependent on other epistemic sources, e.g. a priori intuition or emotion.     

Perceptual reasons

The two main theories of perceptual reasons in contemporary epistemology can be called Phenomenalism and Factualism. According to Phenomenalism, perceptual reasons are facts about experiences conceived of as phenomenal states, i.e., states individuated by phenomenal character, by what it’s like to be in them. According to Factualism, perceptual reasons are instead facts about the external objects perceived. The main problem with Factualism is that it struggles with bad cases: cases where perceived objects are not what they appear (illusions, broadly speaking) or where there is no perceived object at all (hallucinations). The main problem with Phenomenalism is that it struggles with good cases: cases where everything is perfectly normal and the external object is correctly perceived, so that one’s perceptual beliefs are knowledge. In this paper we show that there is a theory of perceptual reasons that avoids the problems for Factualism and Phenomenalism. We call this view Propositionalism. We use ‘proposition’ broadly to mean the entities that are contents of beliefs and other doxastic attitudes. The key to finding a middle ground between Phenomenalism and Factualism, we claim, is to allow our reasons to be false in bad cases. Despite being false, they are about the external world, not our phenomenal states.