从语言到思想:基于指称问题考察分析哲学的范式转移

本文通过追溯当代内容理论的语言哲学和现象学起源,以指称性概念和意向性概念为核心,简要刻画了指称理论和内容理论的发展线索。在此基础上,本文试图借助语言指称问题和心理指称问题的平行关系,为当代分析哲学的主流从语言哲学到心灵哲学的范式转移的动机和方法勾勒出一个考察纲要。     

Processing spatial relations with different apertures of attention

Neuropsychological studies suggest the existence of lateralized networks that represent categorical and coordinate types of spatial information. In addition, studies with neural networks have shown that they encode more effectively categorical spatial judgments or coordinate spatial judgments, if their input is based, respectively, on units with relatively small, nonoverlapping receptive fields, as opposed to units with relatively large, overlapping receptive fields. These findings leave open the question of whether interactive processes between spatial detectors and types of spatial relations can be modulated by spatial attention. We hypothesized that spreading the attention window to encompass an area that includes two objects promotes coordinate spatial relations, based on coarse coding by large, overlapping, receptive fields. In contrast, narrowing attention to encompass an area that includes only one of the objects benefits categorical spatial relations, by effectively parsing space. By use of a cueing procedure, the spatial attention window was manipulated to select regions of differing areas. As predicted, when the attention window was large, coordinate spatial transformations were noticed faster than categorical transformations; in contrast, when the attention window was relatively smaller, categorical spatial transformations were noticed faster than coordinate transformations. Another novel finding was that coordinate changes were noticed faster when cueing an area that included both objects as well as the empty space between them than when simultaneously cueing both areas including the objects while leaving the gap between them uncued.     

Implicit attentional orienting in a target detection task with central cues

Studies using Posner’s spatial cueing paradigm have demonstrated that participants can allocate their attention to specific target locations based on the predictiveness of preceding cues. Four experiments were conducted to investigate attentional orienting processes operating in a high probability condition (cues 75% predictive) as compared to a low probability condition (cues 50% predictive) using various types of centrally-presented cues. Spatially-informative cues (arrows and circles with gaps) resulted in cueing effects (CEs) for both probability conditions, with significantly larger CEs in the high probability conditions than the low probability conditions. Participants in the high probability conditions reported little or no awareness of cue–target probabilities after task completion. Our results provide support for an implicit learning account of the proportion valid effect under experimental conditions involving spatially-informative central cues and relatively short stimulus onset asynchronies (SOAs).     

Bimanual reaching across the hemispace: Which hand is yoked to which?

When both hands perform concurrent goal-directed reaches, they become yoked to one another. To investigate the direction of this coupling (i.e., which hand is yoked to which), the temporal dynamics of bimanual reaches were compared with equivalent-amplitude unimanual reaches. These reaches were to target pairs located on either the left or right sides of space; meaning that in the bimanual condition, one hand's contralateral (more difficult) reach accompanied by the other hand's ipsilateral (easier) reach. By comparing which hand's difficult reach was improved more by the presence of the other hand's easier ipsilateral reach, we were able to demonstrate asymmetries in the coupling. When the cost of bimanual reaching was controlled for the contralateral reaching left hand's performance was improved, suggesting that the left hand is yoked to the right during motor output. In contrast, the right hand showed the greatest improvements for contralateral reaching in terms of reaction time, pointing toward a dominant role for the left hand in the processes prior to movement onset. The results may point toward a mechanism for integrating the unitary system of attention with bimanual coordination.     

Subjective discriminability of invisibility: A framework for distinguishing perceptual and attentional failures of awareness

Conscious visual perception can fail in many circumstances. However, little is known about the causes and processes leading to failures of visual awareness. In this study, we introduce a new signal detection measure termed subjective discriminability of invisibility (SDI) that allows one to distinguish between subjective blindness due to reduction of sensory signals or to lack of attentional access to sensory signals. The SDI is computed based upon subjective confidence in reporting the absence of a target (i.e., miss and correct rejection trials). Using this new measure, we found that target misses were subjectively indistinguishable from physical absence when contrast reduction, backward masking and flash suppression were used, whereas confidence was appropriately modulated when dual task, attentional blink and spatial uncertainty methods were employed. These results show that failure of visual perception can be identified as either a result of perceptual or attentional blindness depending on the circumstances under which visual awareness was impaired.     

绝句韵律边界的认知加工及其脑电效应

语言理解过程中, 句子内部的韵律短语边界会诱发反映韵律短语终止的特异性脑电成分终止正漂移 (CPS, closure positive shift), 而句末语调短语边界则会诱发反映句法终止和完整语言单元结束的脑电效应P3。研究采用汉语特有的语篇绝句, 考察了听者加工绝句中各句末语调短语边界的认知过程及其诱发的脑电效应。结果发现五言绝句内部各语调短语边界分别诱发了时间进程、头皮分布和波幅均相同的CPS, 表明语篇内部韵律边界加工不受其所处语篇位置的影响; 五言和七言绝句末的韵律边界则分别诱发了一个P3, 并且前者诱发的P3波幅小于后者, 而二者在时间进程和头皮分布上不存在差异。本研究表明, 句末语调短语边界诱发何种脑电效应与其承担的功能有关, 既表示前面信息终止又预期后面信息出现的句末边界会诱发CPS, 而只表示信息终止的句末边界则会诱发P3。     

情绪图片的效价与唤醒度在注意瞬脱对抗效应中的作用:来自ERP的证据

以情绪图片为材料,在RSVP任务下检验了效价和唤醒度在注意瞬脱对抗效应中的作用。实验发现效价在对抗注意瞬脱中起主要作用,且正性图片的对抗效应优于负性图片,但唤醒度对注意瞬脱的影响不显著,结果支持积极情绪对抗注意瞬脱的观点。ERP结果进一步发现以上效应发生在P3代表的工作记忆巩固阶段。而在P2和N2代表的早期注意阶段,尽管已出现了注意瞬脱和情绪加工,但二者无显著交互作用。     

Spatial-attention and emotional evocation: line bisection performance and visual art emotional evocation

Lesion studies demonstrate that the right temporal-parietal region (RTP) is important for mediating spatial attention. The RTP is also involved in emotional experiences that can be evoked by art. Normal people vary in their ability to allocate spatial attention, thus, people who can better allocate attention might also be more influenced by the emotional messages of the paintings (evocative impact). Seventeen healthy participants bisected an unlabeled 100mm line and their performance on this task was used to create two groups, individuals who were more (mALB) and less accurate (lALB). These participants also judged 10 paintings on five qualities, Evocative Impact, Aesthetics, Novelty, Technique, and Closure by marking a 100mm line from 1 (low degree) to 10 (high degree). An ANOVA indicated differences in accuracy on the line bisection (LB) between the two groups. Additional ANOVAs, using the quality ratings as the dependent measure, revealed that the mALB group scored the Evocative Impact greater than the lALB group. These results suggest that the differences in attentional bias between the two groups, as indicated by their LB performance, might influence their evocative impact or reactions and also be a 'barometer' of other RTP functions, including emotional processing.     

Intra-individual reaction time variability in schizophrenia, depression and borderline personality disorder

Intra-individual reaction time variability (IIV) in neuropsychological task performance reflects short term fluctuations in performance. Increased IIV has been reported in patients with schizophrenia and could be related to a deficient neural timing mechanism, but the role of IIV in adult patients with other psychiatric disorders has not been established. Therefore, we compared IIV measures obtained in a Go/Nogo task from patients with schizophrenia, major depression and borderline personality disorder. IIV was increased for patients with schizophrenia. When correcting for differences in mean reaction time, depressive and borderline patients also showed increased IIV. Importantly, all groups showed a strong association between IIV and accuracy of task performance. This suggests that increased IIV might be a sensitive marker for the efficiency of top-down attentional control in all diagnostic groups. Aside from these similarities, the complete results including measures of IIV, mean reaction time and accuracy show differential patterns for patients with schizophrenia compared to those with borderline personality disorder or depression. These results are discussed with respect to common versus disorder-specific neural mechanisms underlying increased IIV.     

Disentangling perceptual and motor components in inhibition of return

Following an abrupt onset of a peripheral stimulus (a cue), the response to a visual target is faster when the target appears at the cued position than when it appears at other positions. However, if the stimulus onset asynchrony (SOA) is longer than approximately 300 ms, the response to the target is slower at the cued position than that at other positions. This phenomenon of a longer response time to cued targets is called "inhibition of return" (IOR). Previous hypotheses propose contributions of both response inhibition and attentional inhibition at cued position to IOR, and suggest that responding to the cue can eliminate the component of response inhibition. The current study uses tasks either executing or withholding response to the cue to investigate the relative contributions of response and attention components to IOR. A condition with bilateral display of the cue is also chosen as a control condition, and eight different SOAs between 1,000 and 2,750 ms are tested. Compared to the control condition, response delay to the target at a cued position is eliminated by responding to the cue, and a response advantage to the target at an uncued position is not affected by responding to the cue. Furthermore, both response delay at a cued position and response advantage at an uncued position decrease with SOA in the time window tested in these experiments. The results reported here indicate a dominant response inhibition at a cued position and a primary attentional allocation at an uncued position for IOR. Nonsignificant perceptual/attentional suppression at a cued position is argued to be a benefit for visual detection in a changing world.