970 resultados para Perceptual Rivalry


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Research on naïve physics investigates children’s intuitive understanding of physical objects, phenomena and processes. Children, and also many adults, were found to have a misconception of inertia, called impetus theory. In order to investigate the development of this naïve concept and the mechanism underlying it, four age groups (5-year-olds, 2nd graders, 5th graders, and 8th graders) were included in this research. Modified experimental tasks were used to explore the effects of daily experience, perceptual cues and general information-processing ability on children’s understanding of inertia. The results of this research are: 1) Five- to thirteen-year-olds’ understanding of inertia problems which were constituted by two ogjects moving at the same spped undergoes an L-shaped developmental trend; Children’s performance became worse as they got older, and their performance in the experiment did not necessarily ascend with the improvement of their cognitive abilities. 2) The L-shaped developmental curve suggests that children in different ages used different strategies to solve inertia problems: Five- to eight-year-olds only used heuristic strategy, while eleven- to thirteen-year-olds solved problems by analyzing the details of inertia motion. 3) The different performance between familiar and unfamiliar problems showed that older children were not able to spontaneously transfer their knowledge and experience from daily action and observation of inertia to unfamiliar, abstract inertia problems. 4) Five- to eight-year-olds showed straight and fragmented pattern, while more eleven- to thirteen-year-olds showed standard impetus theory and revised impetus theory pattern, which showed that younger children were influenced by perceptual cues and their understanding of inertia was fragmented, while older children had coherent impetus theory. 5) When the perceptual cues were controlled, even 40 percent 5 years olds showed the information-processing ability to analyze the distance, speed and time of two objects traveling in two different directions at the same time, demonstrating that they have achieved a necessary level to theorize their naïve concept of inertia.

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There is extensive agreement that attention may play a role in spatial stimmlus coding (Lu & Proctor, 1995). Some authors investigated the effects of spatial attention on the spatial coding by using spatial cueing procedure and spatial Stroop task. The finding was that the stroop effects were modulated by spatial cueing. Three hypotheses including attentional shift account, referential coding account, and event integration account were used to explain the modulation of spatial cueing over the spatial Stroop effects. In these previous studies, on validly cued trials, cue and target not only appeared at the same location, but also in the same object, which resulted in both location and object cued. Consequently, the modulation of spatial attentional cueing over spatial Stroop effects was confounded with the role of object-based attention. In the third chapter of this dissertation, using a modification of double rectangles cueing procedure developed by Egly, Driver and Rafal (1994) and spatial Stroop task employed by Lupiáñez and Funes (2005), separate effects of spatial attention and object-based attention on the location code of visual stimuli were investigated. Across four experiments, the combined results showed that spatial Stroop effects were modulate by object-based attention, but not by location-based attention. This pattern of results could be well explained by event integration account, but not by attentional shift account and referential coding account. In the fourth chapter, on the basis of the prior chapter, whether the modulation of attentional cueing on location code occurred at the stage of perceptual identification or response choice was investigated. The findings were that object-based attention modulated spatial Stroop effects and did not modulate the Simon effects, whereas spatial attention did not modulate Stroop and Simon effects. This pattern of results partially replicated the outcome of the previous chapter. The previous studies generally argued that the conflicts of spatial Stroop task and Simon task respectively occurred at at the stage of perceptual identification and response choice. Therefore, it is likely to conclude that the modulation of attention over spatial Stroop effect was mediated by object-based attention, and this modulation occurred at the stage perceptual identification. Considering that the previous studies mostly investigated the effects of attention captured by abrupt onset on the spatial Stroop effects, few studies investigated the effects of attention captured by offset cue on the spatial Stroop effects. The aim of the fifth chapter was to investigate the role of attention induced by offset and abrupt onset cue in the spatial Stroop task. These results showed that attention elicited by offset cue or abrupt onset cue modulated the spatial Stroop effects, which reconciled with event integration account.

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Theories of Visual search generally differentiate between bottom-up control and top-down control. Bottom-up control occurs when visual selection is determined by the stimulus properties in the search field. Top-down control takes place when observers are able to select those stimuli that are in line with their attentional sets. Pure stimulus-driven capture and contingent capture are two main theories on attentional capture by now, in which, theory of pure capture more emphasize bottom-up control, while theory of contingent capture more emphasize top-down control. Besides those two theories, Perceptual load theory of attention provides completely new perspective to explain attentional capture. The aim of this study is to investigate the mechanism of attentional capture in visual search on the basis of the existing theory of attentional capture and Perceptual load theory of attention. Three aspects of questions were explored in this study, which includes: the modulation role of perceptual load on attentional capture; the influence of search mode on attentional capture; and the influence of stimuli’s spatial and temporal characteristics on attentional capture. The results showed that: (1) Attentional capture was modulated by perceptual load in both conditions in which perceptual load manipulated either by amount of stimuli or similarity of stimuli. (2) Search mode did influence attentional capture, but more important, which was also modulated by perceptual load. (3) The spatial characteristics of congruent and incongruent distractor did influence attentional capture, specifically, the further the distractor from the target, the more interference effect the distractor had on visual search. (4) The temporal characteristics of distractor did influence attentional capture, specifically, the pattern of results from the study in which distractor were presented after the search display, were similar to those from the study in which distractors were presented before the search display. In sum, the results indicated that attentional capture are controlled not only by bottom-up factors, top-down factors but also modulated by available attention resources. These findings contribute to resolve the controversy for mechanism of attentional capture. And the potential application of this research was discussed.

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A number of functional neuroimaging studies with skilled readers consistently showed activation to visual words in the left mid-fusiform cortex in occipitotemporal sulcus (LMFC-OTS). Neuropsychological studies also showed that lesions at left ventral occipitotemporal areas result in impairment in visual word processing. Based on these empirical observations and some theoretical speculations, a few researchers postulated that the LMFC-OTS is responsible for instant parallel and holistic extraction of the abstract representation of letter strings, and labeled this piece of cortex as “visual word form area” (VWFA). Nonetheless, functional neuroimaging studies alone is basically a correlative rather than causal approach, and lesions in the previous studies were typically not constrained within LMFC-OTS but also involving other brain regions beyond this area. Given these limitations, it remains unanswered for three fundamental questions: is LMFC-OTS necessary for visual word processing? is this functionally selective for visual word processing while unnecessary for processing of non-visual word stimuli? what are its function properties in visual word processing? This thesis aimed to address these questions through a series of neuropsychological, anatomical and functional MRI experiments in four patients with different degrees of impairments in the left fusiform gyrus. Necessity: Detailed analysis of anatomical brain images revealed that the four patients had differential foci of brain infarction. Specifically, the LMFC-OTS was damaged in one patient, while it remained intact in the other three. Neuropsychological experiments showed that the patient with lesions in the LMFC-OTS had severe impairments in reading aloud and recognizing Chinese characters, i.e., pure alexia. The patient with intact LMFC-OTS but information from the left visual field (LVF) was blocked due to lesions in the splenium of corpus callosum, showed impairment in Chinese characters recognition when the stimuli were presented in the LVF but not in the RVF, i.e. left hemialexia. In contrast, the other two patients with intact LMFC-OTS had normal function in processing Chinese characters. The fMRI experiments demonstrated that there was no significant activation to Chinese characters in the LMFC-OTS of the pure alexic patient and of the patient with left hemialexia when the stimuli were presented in the LVF. On the other hand, this patient, when Chinese characters were presented in right visual field, and the other two with intact LMFC-OTS had activation in the LMFC-OTS. These results together point to the necessity of the LMFC-OTS for Chinese character processing. Selectivity: We tested selectivity of the LMFC-OTS for visual word processing through systematically examining the patients’ ability for processing visual vs. auditory words, and word vs. non-word visual stimuli, such as faces, objects and colors. Results showed that the pure alexic patients could normally process auditory words (expression, understanding and repetition of orally presented words) and non-word visual stimuli (faces, objects, colors and numbers). Although the patient showed some impairments in naming faces, objects and colors, his performance scores were only slightly lower or not significantly different relative to those of the patients with intact LMFC-OTS. These data provide compelling evidence that the LMFC-OTS is not requisite for processing non-visual word stimuli, thus has selectivity for visual word processing. Functional properties: With tasks involving multiple levels and aspects of word processing, including Chinese character reading, phonological judgment, semantic judgment, identity judgment of abstract visual word representation, lexical decision, perceptual judgment of visual word appearance, and dictation, copying, voluntary writing, etc., we attempted to reveal the most critical dysfunction caused by damage in the LMFC-OTS, thus to clarify the most essential function of this region. Results showed that in addition to dysfunctions in Chinese character reading, phonological and semantic judgment, the patient with lesions at LMFC-OTS failed to judge correctly whether two characters (including compound and simple characters) with different surface features (e.g., different fonts, printed vs. handwritten vs. calligraphy styles, simplified characters vs. traditional characters, different orientations of strokes or whole characters) had the same abstract representation. The patient initially showed severe impairments in processing both simple characters and compound characters. He could only copy a compound character in a stroke-by-stroke manner, but not by character-by-character or even by radical-by-radical manners. During the recovery process, namely five months later, the patient could complete the abstract representation tasks of simple characters, but showed no improvement for compound characters. However, he then could copy compound characters in a radical-by-radical manner. Furthermore, it seems that the recovery of copying paralleled to that of judgment of abstract representation. These observations indicate that lesions of the LMFC-OTS in the pure alexic patients caused several damage in the ability of extracting the abstract representation from lower level units to higher level units, and the patient had especial difficulty to extract the abstract representation of whole character from its secondary units (e.g., radicals or single characters) and this ability was resistant to recover from impairment. Therefore, the LMFC-OTS appears to be responsible for the multilevel (particularly higher levels) abstract representations of visual word form. Successful extraction seems independent on access to phonological and semantic information, given the alexic patient showed severe impairments in reading aloud and semantic processing on simple characters while maintenance of intact judgment on their abstract representation. However, it is also possible that the interaction between the abstract representation and its related information e.g. phonological and semantic information was damaged as well in this patient. Taken together, we conclude that: 1) the LMFC-OTS is necessary for Chinese character processing, 2) it is selective for Chinese character processing, and 3) its critical function is to extract multiple levels of abstract representation of visual word and possibly to transmit it to phonological and semantic systems.

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The relationship between exogenous attention and endogenous attention is still unclear. We conclude the result of previous studies and our experiments by proposing a convergence hypothesis. A lot of evidences from ERP and fMRI proved the distinction between exogenous and endogenous attention. The distinction is fit for the complicated surroundings. Some studies found that exogenous and endogenous attention activated some common brain areas but if there’s any common function in these areas was still unclear. Previous studies failed to disentangle the relationship between these two mechanisms in detail, and most of the previous studies compared these two mechanisms separately. We used the cue-target paradigm, controlled the SOA and the cue validity to separate endogenous and exogenous attention. We try to figure out the relationship between endogenous and exogenous attention. We found that, in the exogenous attention condition, the amplitude of the P1 component was larger and the amplitude of N1 was smaller than that in the invalid trials. In the endogenous attention condition, the amplitudes of the P1 and N1 components in valid trials were both larger than that in the invalid trials. The difference wave of endogenous and exogenous attentions showed that at the beginning of their process endogenous and exogenous attentions were separate and then the process was going to converge. The stimuli appear in the visual field will activate the “external trigger” in exogenous attention processing, and then the signal will be transferred to next stage, in the endogenous attention processing, when the observer want to attend, the “inner trigger” will be activated and the signal will be transfered. The difference between “external trigger” and “inner trigger” in endogenous and exogenous attention was significant, so the difference at the beginning of the process was significant. When the signal was transferred to the next processing stage, the difference between the endogenous and exogenous attention became diminished, and it was a convergence process. We used the cue-target paradigm, let the central cue and peripheral cue appear in one trial, try to investigate the relationship between endogenous and exogenous attention under different perceptual load conditions. The result from of difference wave showed that the relationship between the two attentions was consistent with the convergence hypothesis. We also found that under different perceptual load conditions, the relationship between endogenous and exogenous attention was different. The perceptual load has influence on the “external trigger” and “inner trigger”. A cue-target paradigm was used to investigate the relationship between attention, age and perceptual load, we found that the function of visual attention was decrease in the old group, they need more attentional resource when they face the issue. The aging effect has influence on the “external trigger” and “inner trigger”. The effects of age and perceptual load were much higher in exogenous attention condition.

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A dual task paradigm which consisted of RSVP task and orthogonal spatial cuing task was adopted to study the effects of perceptual load and cue modality on attention capture. This dual task paradigm was modified from Santangelo’s tasks in which only the high load condition used the dual task. Experiment 1 found that in the low perceptual load condition, the visual cues showed advantage in capturing attention compared with the audiovisual ones. While in the high perceptual load condition, the audiovisual cues were better to capture attention. SOA was introduced into Experiment 2, 3 and 4 in order to help clarify the relationship among perceptual load, cuing modality and attention capture. The low load visual cuing task testified the period time course characteristics in attention capture which was found by Liang et.al. Differing from Liang’s conclusion that attention capture occurred at 333ms, attention capture occurred at 50ms here which might be caused by the different paradigms used. Moreover, the similar period time course was found in high load audiovisual cuing task when SOA equaled 50ms. And no such period time course characteristics were found neither in the high load visual cuing task nor the low load audiovisual cuing task. These results found the period time course characteristics in attention capture. And it was suggested that these characteristics were influenced by perceptual load and cuing modality.

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In the history of psychology research, more attention had been focused on the relation between local processing and global processing. For the global information and the local information, which is processed earlier? And which is processed faster? Precedence of the global over the local level in visual perception has been well established by Navon with compound stimuli, and Navon’s original study gave rise to many publications, including replications, generalization to other kinds of stimuli (nonverbal material, digits), populations (infants, children, brain-damaged subjects), and tasks (lateral visual hemifield presentation, copy drawing, memory recognition, and recall), and triggered some debate about the conditions in which global precedence is and is not observed (number, size, sparsity, and goodness of the stimuli, exposure duration, etc.). However, whether there is a global advantage or precedence in other cognitive processes was less tested. Most researches had suggested that there was a functional equivalency between visual perception and visual image processing. However, it’s still unknown whether there will be a global advantage on mental rotation. In the present study, we combined the mental rotation task with the compound stimuli to explore whether the global or local advantage also existed at the mental imagery transformation stages. In two pilot studies, the perceptual global precedence was found to be present in a normal/mirror-image judgment task when the stimuli exposure time was short; while the stimuli exposure time was prolonged (stimuli kept available till subjects’ response) the perceptual global precedence was showed to be eliminated. In all of the subsequent experiments, stimili would be presented till subjects’ response. Then mental rotation was added in normal/mirror-image judgment (some of the stimuli were rotated to certain angles from upright) in normal experiments, experiment 1 and 2 observed a global advantage on mental rotation both with a focused-attention design (Experiment 1) and divided-attention design (Experiment 2). Subjects’ reaction times were increased with rotation angles, and the accuracy was decreased with rotation angles, suggesting that subject need a mental rotation to make a normal/mirror judgment. The most important results were that subjects’ response to global rotation was faster than that to local rotation. The analysis of slope of rotation further indicated that, to some extend, the speed of global rotation was faster than that of local rotation. These results suggest a global advantage on mental rotation. Experiment 3 took advantage of the high temporal resolution of event-related potentials to explore the temporal pattern of global advantage on mental rotation. Event-related potential results indicated the parietal P300 amplitude was inversely related to the character orientation, and the local rotation task delayed the onset of the mental-rotation-related negativity at parietal electrodes. None clear effect was found for occipital N150. All these results suggested that the global rotation was not only processed faster than local rotation, but also occurred earlier than local rotation. Experiments 4 and 5 took the effect size of global advantage as the main dependent variable, and visual angle and exposure duration of the stimuli as independent variables, to examine the relationship between perceptual global precedence and global advantage on mental rotation. Results indicated that visual angle and exposure duration did not influence the effect size of global advantage on mental rotation. The global advantage on mental rotation and the perceptual global advantage seemed to be independent but their effects could be accumulated at some condition. These findings not only contribute to revealing a new processing property of mental rotation, but also deepen our understanding of the problem of global/local processing and shed light on the debate on locus of global precedence.

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Crowding, generally defined as the deleterious influence of nearby contours on visual discrimination, is ubiquitous in spatial vision. Specifically, long-range effects of non-overlapping distracters can alter the appearance of an object, making it unrecognizable. Theories in many domains, including vision computation and high-level attention, have been proposed to account for crowding. However, neither compulsory averaging model nor insufficient spatial esolution of attention provides an adequate explanation for crowding. The present study examined the effects of perceptual organization on crowding. We hypothesize that target-distractor segmentation in crowding is analogous to figure-ground segregation in Gestalt. When distractors can be grouped as a whole or when they are similar to each other but different from the target, the target can be distinguished from distractors. However, grouping target and distractors together by Gestalt principles may interfere with target-distractor separation. Six experiments were carried out to assess our theory. In experiments 1, 2, and 3, we manipulated the similarity between target and distractor as well as the configuration of distractors to investigate the effects of stimuli-driven grouping on target-distractor segmentation. In experiments 4, 5, and 6, we focused on the interaction between bottom-up and top-down processes of grouping, and their influences on target-distractor segmentation. Our results demonstrated that: (a) when distractors were similar to each other but different from target, crowding was eased; (b) when distractors formed a subjective contour or were placed regularly, crowding was also reduced; (c) both bottom-up and top-down processes could influence target-distractor grouping, mediating the effects of crowding. These results support our hypothesis that the figure-ground segregation and target-distractor segmentation in crowding may share similar processes. The present study not only provides a novel explanation for crowding, but also examines the processing bottleneck in object recognition. These findings have significant implications on computer vision and interface design as well as on clinical practice in amblyopia and dyslexia.

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In 7 experiments, the authors examined the perceptual and cognitive processes used to track the locations of objects during locomotion. Participants learned locations of 9 objects on the outer part of a turntable from a single viewpoint while standing in the middle of the turntable. They subsequently pointed to objects while facing the learning heading and a new heading, using imagined headings that corresponded to their current actual body heading and the other actual heading. Participants in 6 experiments were asked to imagine that the objects moved with them as they turned and were shown or only told that the objects would move with them; in Experiment 7, participants were shown that objects could move with them but were asked to ignore this as they turned. Results showed that participants tracked object locations as though the objects moved with them when shown but not when told about the consequences of their locomotion. Once activated, this processing mode could not be suppressed by instructions. Results indicated that people process object locations in a body- or an environment-stabilized manner during locomotion, depending on the perceptual consequences of locomotion.

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The core issue of the current study is on the strength difference of strong foci led by different syntactic devices (focus marker、focus operator、exclusive quantifier)and their acoustic perceptual different in “sentence with multiple strong foci”. The research methods adopted were text labeling and acoustic perceptual experiment. The acoustic parameters of the two speakers in the experiment were analyzed and discussed. The main results of the current study are as follows: Utilizing “sentence with multiple strong foci” as research material, text labeling and acoustic perceptual experiment as research method, the present study performed pairwise comparison of the focus led by focus marker and its corresponding syntactic structure, exclusive quantifier and focus sensitive operator. The results reveal that: in the text labeling experiment and acoustic perceptual experiment, the focus led by focus marker and its corresponding syntactic structure are higher in strength than that led by exclusive quantifier, which in turn leads to more intensive focus strength than focus sensitive operator; in the text labeling experiment, experimental results reveal that foci led by focus marker and its corresponding syntactic structure are higher in strength than that led by the focus sensitive operator. The main conclusions of the current study are as follows: 1 The experimental result supports the assumption to separate the “exclusive quantifier” from the traditional “focus sensitive operator” and treat it as an independent syntactic device leading focus. 2 Paired-Samples T-Text demonstrated that the foci led by the three different syntactic devices differed in the aspect of strengths 3 Syntactic device plays a fundamental role in the determination of focus strength while phonetic device facilitates the determination of focus identification.

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Relapse has been a great challenge in clinical treatment and experimental studies of drug addiction. Recent studies suggest that psychological dependence may play a major role in addiction relapse, even more important than physiological dependence. Then a fundamental question arises: how to measure the psychological dependence? How to examine whether an addict has psychologically quitted when leaving drug rehabilitation centers? Self-report, a commonly used evaluation approach, is inevitably vulnerable to various cognitive influences, particularly in explicit tasks. Therefore, an objective index is necessary to evaluate the subliminal psychological drug dependence level. The objective of the current study was to develop such a psychological paradigm to probe the unaware attentional bias of in smoking addicts. Experiment 1 adapted the interocular suppression technique of binocular rivalry to study the attentional bias to cigarette pictures in smokers and age-matched nonsmoker. Results show that the smokers demonstrated similar attentional bias in both visible and unaware conditions, while non-smokers showed attentional bias only in the visible condition, and there was a significant interaction between experiment conditions and subject groups. These results provide compelling evidence for addiction-specific attentional bias in cigarette smokers, by minimizing the influence of confounding conscious factors. Furthermore, attentional bias of smokers in unawareness state was negatively correlated with their cigarette dependence levels, while their pre-test cigarette craving levels was positively correlated with their attnetional bias in the visible condition. This pair of correlations further demonstrated the advantages of unawareness state in disclosing stable dependence states, therefore supporting the effectiveness of the paradigm used in this study. Another interesting finding of Experiment 1 is that non-smokers also showed attentional bias in the visible condition. To exclude the possibility that the attentional bias found in experiment 1 was task-specific, experiment 2 adapted the most commonly-used visual dot probe task with smoking scenes as in relevant reference. The result in experiment 1 was well replicated, i.e., nonsmokers in experiment 2 also showed significant attentional bias to smoking-related stimuli, We interpenetrate this interesting finding as an effect of environmental influence, as the participants of the current study live in a highly smoking-exposed and smoking-encouraged environment, which is quite different with the participants of studies reported in the literature. A series of questionnaires and scales administered in the current study indeed show that most smokers smoked due to influence of the environment. They also acknowledged that smoking as an important media of social communication in China, and even considered that away from the smoking environment would effectively help them to quit. The current study also found that the disgust level towards cigarette pictures and smoking-related scenes of non-smokers was positively correlated with their attnentional bias in the visible condition of experiment 1. It is likely that in a highly smoking-encouraged environment, the remaining few on-smokers have severe disgust to cigarettes and smoking scenes; and their attentional bias might be caused by disgust avoidance. In conclusion, the current study represents the first study showing the existence of unaware attentional bias to smoking related stimuli in cigarette smokers by applying the interocular suppression paradigm, providing a reference to study of dependence of other drugs. The current study also found that our non-smoking participants also showed attentional bias to smoking related stimuli, which may be due to the possible influence of highly smoking-exposed environment of our participants.

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The important basis for the children to study chinese character is the Chinese character awareness, which means the understanding and extracting of the Chinese character combinatorial rule. The perceptual learning intrinsically is the direct perceive to the invariant rules. As the important mechanism to extract the abstract rule, the perceptual learning is the important mechanism of the development of the Chinese character awareness also. 4-6-year-old children's Chinese character awareness are tested by the degree of acceptance to the graphic words, inlaying words and pseudowords. The perceptual disintegration are tested by the perceptual learning experiment. Moreover, the development of the ability to finely-identify the Chinese character under the different level of attention condition is explored. The result suggests the quality to the development of the children's Chinese character awareness: The Chinese character awareness to 4-year-old children is in the rudiment stage, and it have different qualities as the change of the age. As the mechanism of the Chinese character awareness, the perceptual learning have an complex correlation to the awareness. The result indicates the following effects of the children perceptual disintegration: the level of the perceptual disintegration is transitive from three-dimension confusion to one-dimension falsity. It have correlation with the ability to finely-identify the Chinese character to a certain degree. The result also shows: the developmental specialties of the ability to finely-identify the Chinese character are different in the different age. The ability to finely-identify the Chinese character under the different level of attention condition have very similar processes.

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Human being built and updated the representations of spatial distances and spatial relations between protagonist and the around things in language comprehension. The representations of the spatial relations in egocentric spatial situational models were important in spatial cognition, narrative comprehension and psycholinguistic. Using imagery searching paradigm, Franklin and Tversky (1990) studied the representations of the spatial relations in egocentric spatial situational models and found the standard RT pattern of searching the objects in different directions around the observer (frontperceptual space(Hintzman, 1981). Eight experiments were conducted to distinguish the factors that affected the RT pattern in imagery searching. Rt. patterns in experiments 1, 2, 3, showed that there were two factors in identify which object was currently located beyond the observer's front, back, right, and left. The first factor (called direction effect) was for identifying the referred direction of probing noun, with a pattern of process time frontperceptual representation (the position of objects around body) was required in searching task (from direction nouns to objects). The mapping needs the body of observer as reference frame. The body are designed asymmetry, so there are effects of direction, while as The arrows pointing to four directions around body map directly to the position around body; In spatial memory, the difficulty of retrieving objects in front, back, right or left is different(front=right=left

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By now, there are still many unsolved questions about associative priming. This study used process dissociation paradigm, perceptual identification task and speeded naming task,together with near infrared spectroscopy, to investigate priming for new associations and its brain mechanisms systematically. The results showed there was interaction between level of processing and unitization in affecting associative priming. When comparing with shallow encoding unrelated word pairs, the activation of both sides of prefrontal lobe was stronger, which suggested prefrontal lobe had relations with memory for new associations. Medial temporal lobe and frontal lobe lesioned patients were tested respectively using methods of perceptual identification task and speeded naming task. Both brain regions participated in associative priming. Medial temporal lobe mediated unitization between unrelated items. Frontal lobe contributed to priming for new associations by elaborative processing, inhibiting irrelevant information, selective attending to tasks, and establishing some effective strategies. In addition, normal subjects needed to aware the relationship between study and test to form associative priming and densely memory deficit patients could not form memory for new associations. In conclusion, the results further demonstrated that perceptual representation system could not support priming for new associations alone. Medial temporal lobe and frontal lobe played roles in priming for new associations, and there was some relation between associative priming and conscious retrieval processing.

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This research, mainly by using perceptual experiment and relating its results to the acoustic correlates, investigated the acoustic correlates of mandarin prominences of prosodic word、prosodic phrase、sentence and their mutual influences. The results are as follow: (1) for the prominence of prosodic word, according the order of the extents to which these acoustic correlates contribute to the perception of the prominence, its acoustic correlates are duration、pitch、spectral tilt、energy and pitch-change, the results also have showed that the perception of the prominence is influenced by some non-acoustic factors; (2) for the prominence of prosodic phrase, baseing on the experimental results, the existing of prosodic phrase prominence in mandarian has been proposed, and the experiments proved that the prosodic phrase prominence fall on the semantic focus of the phrase typically; (3) for the prominence of sentence, the experimental results show that, the lengthening of duration, similar with the pitch-change, mainly localised on the prosodic head of the domain on which the sentence prominence emphisize, and this lengthening would, in different levels, spread on other syllables in the phonetic constituents which contain the prosodic head, and this pattern of lengthening of duration does not vary with changing of domain of sentence prominence, that means, in mandarin sentence, there is generally no acoustic cues which can been used in the perception of the domain of sentnece prominence; (4) for the acoustic cues of mutual influences of the prominences of different levels, the experiment have proved that, not only the pitch-change but also the lengthening of duration are subjective to melodic grid law. In the last part of the dissertation, I have tried to given an explantion about the above experimental results from psylogical view point.