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Transposing two words in a sentence (e.g. "cat" and "was" in "the white cat was big") creates a sequence that is harder to classify as ungrammatical than control sequences (e.g. "the white was cat slowly"), suggesting that word position coding is noisy and can be affected by syntactic expectations. In the present research, this transposed-word effect was examined more closely using Rapid Serial Visual Presentation (RSVP) formats which provided either clear temporal cues to word order but no spatial cues, or both types of cues. Compared to when all words were presented simultaneously, the two RSVP formats reduced the transposed-word effect to the same degree while having no parallel impact on another ungrammatical comparison condition involving no transposition. These results are discussed in the context of serial and parallel models of reading as well as models that propose a later processing stage for the locus of the transposed-word effect. [ABSTRACT FROM AUTHOR]

We investigated age-related differences in serial and strategic processing during the encoding and retrieval of high-value words. Younger and older adults were presented with word triads positioned left, center, and right, with one word being more valuable than the others. In Experiment 1, younger adults more effectively recalled the middle, high-value word, demonstrating enhanced strategic memory. Younger adults were more likely to initiate recall with a high-value word whereas older adults were equally likely to initiate recall with a left and high-value word. Additionally, older adults were more likely to recall words in their presented order while younger adults strategically recalled successive high-value words. However, both age groups demonstrated strategic processing in Experiments 2 and 3, even without prior knowledge of the high-value word’s location. Thus, serial and strategic processing may differ based on age and task demands, but strategic processing is preserved in older adults in certain contexts. [ABSTRACT FROM AUTHOR]

Studies using a grammaticality decision task have revealed surprising flexibility in the processing of word order during sentence reading in both alphabetic and non-alphabetic scripts. Participants in these studies typically exhibit a transposed-word effect, in which they make more errors and slower correct responses for stimuli that contain a word transposition and are derived from grammatical as compared to ungrammatical base sentences. Some researchers have used this finding to argue that words are encoded in parallel during reading, such that multiple words can be processed simultaneously and might be recognised out of order. This contrasts with an alternative account of the reading process, which argues that words must be encoded serially, one at a time. We examined, in English, whether the transposed-word effect provides evidence for a parallel-processing account, employing the same grammaticality decision task used in previous research and display procedures that either allowed for parallel word encoding or permitted only the serial encoding of words. Our results replicate and extend recent findings by showing that relative word order can be processed flexibly even when parallel processing is not possible (i.e., within displays requiring serial word encoding). Accordingly, while the present findings provide further evidence for flexibility in the processing of relative word order during reading, they add to converging evidence that the transposed-word effect does not provide unequivocal evidence for a parallel-processing account of reading. We consider how the present findings may be accounted for by both serial and parallel accounts of word recognition in reading. [ABSTRACT FROM AUTHOR]

The process of word recognition can be analytic (or serial) or holistic (or parallel). They differ in the size of the processing units (lexical vs. sublexical) or in whether sublexical units are processed sequentially or simultaneously. First language (L1) reading development has been found to involve a transition from serial processing to parallel processing, as shown in a decreasing length or stroke number effect among readers of increasing proficiencies. The present study was intended to explore the use of analytic versus holistic character recognition strategies in the second language (L2) learners, an issue that has not received much attention. Chinese native speakers and learners of Chinese as a second language (CSL) were tested in a variant of the lexical decision task on Chinese characters of different numbers of strokes. Regression analyses with reaction times as an outcome variable and stroke number as a predictor variable showed that CSL speakers produced a stroke number effect where native speakers did not. The results were interpreted as evidence for the employment of an analytic processing strategy by L2 speakers. The findings raised several important issues for future research and for pedagogical considerations. The Challenge: Little is known about whether adult L2 Chinese learners process Chinese characters holistically as developed Chinese native readers do, or analytically as beginning readers do. The present study explored this issue in a carefully designed experimental setting and obtained evidence for the analytical processing of Chinese characters by L2 learners. Pedagogical implications Table A1 for this finding were discussed. [ABSTRACT FROM AUTHOR]

Does recognizing the transformations that gave rise to an object's retinal image contribute to early object recognition? It might, because finding a partially occluded object among similar objects that are not occluded is more difficult than finding an object that has the same retinal image shape without evident occlusion. If this is because the occlusion is recognized as such, we might see something similar for other transformations. We confirmed that it is difficult to find a cookie with a section missing when this was the result of occlusion. It is not more difficult to find a cookie from which a piece has been bitten off than to find one that was baked in a similar shape. On the contrary, the bite marks help detect the bitten cookie. Thus, biting off a part of a cookie has very different effects on visual search than occluding part of it. These findings do not support the idea that observers rapidly and automatically compensate for the ways in which objects' shapes are transformed to give rise to the objects' retinal images. They are easy to explain in terms of detecting characteristic features in the retinal image that such transformations may hide or create. [ABSTRACT FROM AUTHOR]

Intense interests are a core symptom of autism spectrum disorders (ASD) and can be all-encompassing for affected individuals. This observation raises the hypothesis that intense interests in ASD are related to pervasive changes in visual processing for objects within that category, including visual search. We assayed visual processing with two novel tasks, targeting category search and exemplar search. For each task, three kinds of stimuli were used: faces, houses, and images personalized to each participant’s interest. 25 children and adults with ASD were compared to 25 neurotypical (NT) children and adults. We found no differences in either visual search task between ASD and NT controls for interests. Thus, pervasive alterations in perception are not likely to account for ASD behavioral symptoms.

Intense interests are a core symptom of autism spectrum disorders (ASD) and can be all-encompassing for affected individuals. This observation raises the hypothesis that intense interests in ASD are related to pervasive changes in visual processing for objects within that category, including visual search. We assayed visual processing with two novel tasks, targeting category search and exemplar search. For each task, three kinds of stimuli were used: faces, houses, and images personalized to each participant's interest. 25 children and adults with ASD were compared to 25 neurotypical (NT) children and adults. We found no differences in either visual search task between ASD and NT controls for interests. Thus, pervasive alterations in perception are not likely to account for ASD behavioral symptoms. [ABSTRACT FROM AUTHOR]

We introduce a novel method capable of dissecting the succession of processing stages underlying mental arithmetic, thus revealing how two numbers are transformed into a third. We asked adults to point to the result of single-digit additions and subtractions on a number line, while their finger trajectory was constantly monitored. We found that the two operands are processed serially: the finger first points toward the larger operand, then slowly veers toward the correct result. This slow deviation unfolds proportionally to the size of the smaller operand, in both additions and subtractions. We also observed a transient operator effect: a plus sign attracted the finger to the right and a minus sign to the left and a transient activation of the absolute value of the subtrahend. These findings support a model whereby addition and subtraction are computed by a stepwise displacement on the mental number line, starting with the larger number and incrementally adding or subtracting the smaller number.

In most environments, the visual system is confronted with many relevant objects simultaneously. That is especially true during reading. However, behavioral data demonstrate that a serial bottleneck prevents recognition of more than one word at a time. We used fMRI to investigate how parallel spatial channels of visual processing converge into a serial bottleneck for word recognition. Participants viewed pairs of words presented simultaneously. We found that retinotopic cortex processed the twowords in parallel spatial channels, one in each contralateral hemisphere. Responses were higher for attended than for ignored words but were not reduced when attention was divided. We then analyzed two word-selective regions along the occipitotemporal sulcus (OTS) of both hemispheres (subregions of the visual word form area, VWFA). Unlike retinotopic regions, each word-selective region responded to words on both sides of fixation. Nonetheless, a single region in the left hemisphere (posterior OTS) contained spatial channels for both hemifields that were independently modulated by selective attention. Thus, the left posterior VWFA supports parallel processing of multiple words. In contrast, activity in amore anteriorword-selective region in the left hemisphere (mid OTS) was consistent with a single channel, showing (i) limited spatial selectivity, (ii) no effect of spatial attention on mean response amplitudes, and (iii) sensitivity to lexical properties of only one attended word. Therefore, the visual system can process two words in parallel up to a late stage in the ventral stream. The transition to a single channel is consistent with the observed bottleneck in behavior. [ABSTRACT FROM AUTHOR]

The scientific study of reading has long been animated by questions of parallel vs. serial processing. Do readers recognize words serially, adding each one sequentially to a representation of the sentence structure? One fascinating phenomenon to emerge from this research is the transposed word effect : when asked to judge whether sentences are grammatical, readers often fail to notice grammatical errors caused by transposing two words. This effect could be evidence that readers recognize multiple words in parallel. Here we provide converging evidence that the transposed word effect is also consistent with serial processing because it occurs robustly when the words in each sentence are presented serially. We further investigated how the effect relates to individual differences in reading speed, to gaze fixation patterns, and to differences in difficulty across sentences. In a pretest, we first measured the natural English reading rate of 37 participants, which varied widely. In a subsequent grammatical decision task, we presented grammatical and ungrammatical sentences in two modes: one with all words presented simultaneously, and the other with single words presented sequentially at each participant's natural rate. Unlike prior studies that used a fixed sequential presentation rate, we found that the magnitude of the transposed word effect was at least as strong in the sequential presentation mode as in the simultaneous mode, for both error rates and response times. Moreover, faster readers were more likely to miss transpositions of words presented sequentially. We argue that these data favor a "noisy channel" model of comprehension in which skilled readers rely on prior knowledge to rapidly infer the meaning of sentences, allowing for apparent errors in spatial or temporal order, even when the individual words are recognized one at a time. [ABSTRACT FROM AUTHOR]

Besides the fundamental competition between the top-down and bottom-up approaches in nanotechnology, there are some basic aspects for organizing structures and functions at the molecular level. The recent challenges to the development of nanotechnology are marked by a group of general requirements: selection of suited building units, overcoming the restrictions of planar technology, shrinking of nanofabrication facilities, sustainable production and management of life cycles, organization of autonomy and communication at the nano-level, and the optimization of power consumption and energy management. Looking at the natural principles in the construction, synthesis, and function of proteins helps in understanding the principal differences between the currently applied technologies and the characteristics of biomolecular mechanisms in cells. This view allows formulating seven basic rules to meet the general requirements for future developments in molecular nanotechnology.

Humans can pronounce a nonword (e.g., rint). Some researchers have interpreted this behavior as requiring a sequential mechanism by which a grapheme-phoneme correspondence rule is applied to each grapheme in turn. However, several parallel-distributed processing ( PDP) models in English have simulated human nonword reading accuracy without a sequential mechanism. Interestingly, the Japanese psycholinguistic literature went partly in the same direction, but it has since concluded that a sequential parsing mechanism is required to reproduce human nonword reading accuracy. In this study, by manipulating the list composition (i.e., pure word/nonword list vs. mixed list), we demonstrated that past psycholinguistic studies in Japanese have overestimated human nonword reading accuracy. When the more fairly reevaluated human performance was targeted, a newly implemented Japanese PDP model simulated the target accuracy as well as the error patterns. These findings suggest that PDP models are a more parsimonious way of explaining reading across various languages. [ABSTRACT FROM AUTHOR]

There has been evidence for the very brief, temporal quantization of perceptual experience at regular intervals below 100 ms for several decades. We briefly describe how earlier studies led to the concept of ‘psychological moment’ of between 50-60 ms duration. According to historical theories, within the psychological moment all events would be processed as co-temporal. More recently, a link with physiological mechanisms has been proposed, according to which the 50–60 ms psychological moment would be defined by the upper limit required by neural mechanisms to synchronize and thereby represent a snapshot of current perceptual event structure. However, our own experimental developments also identify a more fine-scaled, serialized process structure within the psychological moment. Our data suggests that not all events are processed as co-temporal within the psychological moment and instead, some are processed successively. This evidence questions the analog relationship between synchronized process and simultaneous experience and opens debate on the ontology and function of ‘moments’ in psychological experience.

Visual search is central to the investigation of selective visual attention. Classical theories propose that items are identified by serially deploying focal attention to their locations. While this accounts for set-size effects over a continuum of task difficulties, it has been suggested that parallel models can account for such effects equally well. We compared the serial Competitive Guided Search model with a parallel model in their ability to account for RT distributions and error rates from a large visual search data-set featuring three classical search tasks: 1) a spatial configuration search (2 vs. 5); 2) a feature-conjunction search; and 3) a unique feature search (Wolfe, Palmer & Horowitz Vision Research, 50(14), 1304-1311, 2010). In the parallel model, each item is represented by a diffusion to two boundaries (target-present/absent); the search corresponds to a parallel race between these diffusors. The parallel model was highly flexible in that it allowed both for a parametric range of capacity-limitation and for set-size adjustments of identification boundaries. Furthermore, a quit unit allowed for a continuum of search-quitting policies when the target is not found, with 'single-item inspection' and exhaustive searches comprising its extremes. The serial model was found to be superior to the parallel model, even before penalizing the parallel model for its increased complexity. We discuss the implications of the results and the need for future studies to resolve the debate. [ABSTRACT FROM AUTHOR]

There has been evidence for the very brief, temporal quantization of perceptual experience at regular intervals below 100 ms for several decades. We briefly describe how earlier studies led to the concept of "psychological moment" of between 50 and 60 ms duration. According to historical theories, within the psychological moment all events would be processed as co-temporal. More recently, a link with physiological mechanisms has been proposed, according to which the 50-60 ms psychological moment would be defined by the upper limit required by neural mechanisms to synchronize and thereby represent a snapshot of current perceptual event structure. However, our own experimental developments also identify a more fine-scaled, serialized process structure within the psychological moment. Our data suggests that not all events are processed as co-temporal within the psychological moment and instead, some are processed successively. This evidence questions the analog relationship between synchronized process and simultaneous experience and opens debate on the ontology and function of "moments" in psychological experience. [ABSTRACT FROM AUTHOR]

The current study examined the role of serial processing of newly learned sound–symbol associations in early reading acquisition. A computer-based sound–symbol paradigm (SSP) was administered to 243 children during their last year of kindergarten (T1), and their reading performance was assessed 1 year later in first grade (T2). Results showed that performance on the SSP measured before formal reading instruction was associated with later reading development. At T1, early readers performed significantly better than nonreaders in learning correspondences between sounds and symbols as well as in applying those correspondences in a serial manner. At T2, SSP performance measured at T1 was positively associated with reading performance. Importantly, serial application of newly learned correspondences at T1 explained unique variance in first-grade reading performance in nonreaders over and above other verbal predictors, including phonological awareness, verbal short-term memory, and rapid automatized naming. Consequently, the SSP provides a promising way to study aspects of reading in preliterate children. [ABSTRACT FROM AUTHOR]

The lateral prefrontal cortex and the basal ganglia are known to be important for response selection processes, also in dual-task situations. However, response selection in dual-task situations can be achieved using different modes ranging from a parallel selection to a more serial selection of responses. Nothing is known whether differences in these processing modes during dual-tasking have distinct functional neuroanatomical correlates. In this fMRI study we analyzed performance in a psychological refractory period paradigm. In this paradigm we design a PRP task where we vary the frequency of short and long stimulus onset asynchronies between the two tasks. Using mathematical constraints we interpret the effects of this manipulation with respect to processing modes ranging from more serial to more parallel response selection. Contrastingly these blocks showed that response selection in dual-tasking under the constraint of more parallel processing is mediated by mechanisms operating at the striatal level, while response selection under the constraint of more serial processing is mediated via mechanisms operating in the lateral prefrontal cortex. The results suggest that lateral prefrontal and striatal regions are 'optimized' for a certain processing modes in dual tasking. [ABSTRACT FROM AUTHOR]

People often rely on habitual, serial processing when presented with to-be-learned information. We tested how strategic processing can override more bottom-up, serial processes when remembering information by having participants study a list of word triads (e.g., "dollar phone pizza"). Participants' goal was manipulated by maximizing either (i) their recall for each of the studied words or (ii) their total score associated with recalling certain words in each triad that were more valuable (worth more points) to engage either serial or strategic processing and retrieval mechanisms. Results revealed that when learners were told to maximize their total recall, they frequently engaged in serial remembering-remembering guided by an item's location within the study phase (i.e., words were retrieved according to a habitual reading bias). However, when words were paired with point values that counted towards participants' scores if recalled, participants were not only selective for high-value words but also attempted to overcome the tendency to engage in serial remembering; instead, they appeared to engage in strategic remembering whereby retrieval is guided by value. Thus, to maximize memory utility, it may be beneficial to override habitual processes and initiate retrieval with high-value words, and when making recall transitions, to recall high-value words together. Importantly, when certain to-be-remembered words were more valuable than their neighbors, participants still demonstrated some serial processing of the to-be-remembered words, indicating that even when engaging in strategic memory, some habitual processes can persist. [ABSTRACT FROM AUTHOR]

In this work we study a Hebbian neural network, where neurons are arranged according to a hierarchical architecture such that their couplings scale with their reciprocal distance. As a full statistical mechanics solution is not yet available, after a streamlined introduction to the state of the art via that route, the problem is consistently approached through signal-to-noise technique and extensive numerical simulations. Focusing on the low-storage regime, where the amount of stored patterns grows at most logarithmical with the system size, we prove that these non-mean-field Hopfield-like networks display a richer phase diagram than their classical counterparts. In particular, these networks are able to perform serial processing (i.e. retrieve one pattern at a time through a complete rearrangement of the whole ensemble of neurons) as well as parallel processing (i.e. retrieve several patterns simultaneously, delegating the management of different patterns to diverse communities that build network). The tune between the two regimes is given by the rate of the coupling decay and by the level of noise affecting the system. The price to pay for those remarkable capabilities lies in a network’s capacity smaller than the mean field counterpart, thus yielding a new budget principle: the wider the multitasking capabilities, the lower the network load and vice versa. This may have important implications in our understanding of biological complexity. [ABSTRACT FROM AUTHOR]

The anatomy of the somatosensory system allows both serial and parallel information flow but the conditions involving each mode of processing is a matter of debate. In this functional magnetic resonance imaging (fMRI) study, cutaneous electrical stimulation was applied to human volunteers at three intensities (low-innocuous, moderate-noxious and high-noxious) to investigate interactions between contralateral primary and secondary somatosensory cortices (S1c and S2c), and between contralateral and ipsilateral S2 (S2c and S2i), using dynamic causal modeling (DCM). Our results are consistent with serial processing with a key role of the direct input to S1c for all three intensity levels. The more intense stimulus also induced significantly more interactions between S2i and S2c, consistent with an increase in inter-hemispheric integration associated with the additional recruitment of nociceptive inputs. However, stronger pain reports were also associated with reduced information flow from S1c to S2c at both the moderate (r = -0.81, p = 0.004) and the high stimulation level (r = -0.63, p = 0.037). These findings suggest that the connectivity pattern driven by innocuous inputs is modified by the additional activation of nociceptive afferents. [ABSTRACT FROM AUTHOR]

Following the Sixth International Workshop on Language Production (Edinburgh, UK, Sept., 2010), this special issue presents a collection of contributions concerned with a wide range of representational and processing components. In the present article, we review the evidence for parallel processing at different levels within the production system with the aim of identifying any generalisation or common characteristics that might underpin a robust model of language production. Our review synergises with the other articles of the special issue. After reviewing the literature, we conclude that the evidence for parallelism is stronger at some levels than at others and it is premature to take a strong stand for a unified principle that applies equally to all components of the production system. Following our review, we introduce the other articles represented within this special issue. [ABSTRACT FROM AUTHOR]

Event-related potential studies using delayed match-to-sample tasks have demonstrated the presence of two components, N270 and N400, possibly reflecting the sequential processing of multiple sources of endogenous mismatch. To date, studies have only investigated mismatch between a single cue and target. In this study, we used distractor stimuli to investigate the effect of a secondary source of mismatch distinct from the task-relevant stimulus. Subjects performed two paradigms in which the cue and target could match or mismatch. In one paradigm, task-irrelevant distractors were added-producing a source of task-irrelevant perceptual mismatch. A mismatch-triggered negativity was elicited in both paradigms, but was delayed and enhanced in magnitude in the distractors present paradigm. It is suggested that the distractors may differentially affect mismatch responses through the generation of a task-irrelevant mismatch response. [ABSTRACT FROM AUTHOR]

Highlights: [•] MVPA is often used to detect static fMRI activation patterns. [•] Adapting MVPA to time-resolved signals can characterize the dynamics of neural responses. [•] The temporal generalization matrix reveals a repertoire of canonical brain dynamics. [Copyright &y& Elsevier]

Research on neural models for cognition suggests that thought is far from a simply serial process. Nonetheless, there has been relatively little work on which parameters govern just what aspects of thought are parallel and what are serial. Clearly, speech as such is serial. In consequence, interior monologue (understood as subvocalised speech) is serial. Moreover, stream of consciousness - mental experience not confined to subvocalised speech - must be articulated in serial form in a novel. Due to this constraint on representation, it seems that novelists commonly imagine that stream of consciousness itself really is serial. Joyce, however, developed a sense of parallel cognitive processing in the course of Ulysses. Specifically, in the 'Wandering Rocks' episode, he explored spatiotemporally parallel events in complex social systems. In the following chapter, 'Sirens,' he in effect transferred this treatment of external parallelism to the human mind, systematically developing cognitive parallelism in his representation of Leopold Bloom. This development was perhaps reinforced by ideas of harmony and counterpoint associated with the episode's musical model. Understanding Joyce's exploration of parallel and serial processes in thought is important not only for what it tells us about Ulysses. It is also important for what it contributes to our understanding of cognitive parallelism. [ABSTRACT FROM AUTHOR]

The study of eye movements has proven to be one of the most successful approaches in research on reading. In this overview, it is argued that a major reason for this success is that eye movement measurement is not just a methodology—the control of eye movements is actually part and parcel of the dynamics of information processing within the task of reading itself. Some major developments over the last decade are discussed with a focus on the issue of spatially distributed word processing and its relation to the development of reading models. The survey ends with a description of two newly emerging trends in the field: the study of continuous reading in non-Roman writing systems and the broadening of the scope of research to encompass individual differences and developmental issues. [ABSTRACT FROM AUTHOR]

We present a novel lexical decision task and three boundary paradigm eye-tracking experiments that clarify the picture of parallel processing in word recognition in context. First, we show that lexical decision is facilitated by associated letter information to the left and right of the word, with no apparent hemispheric specificity. Second, we show that parafoveal preview of a repeat of wordnat wordn +1 facilitates reading of wordnrelative to a control condition with an unrelated word at wordn +1. Third, using a version of the boundary paradigm that allowed for a regressive eye movement, we show no parafoveal “postview” effect on reading wordnof repeating wordnat wordn –1.Fourth, we repeat the second experiment but compare the effects of parafoveal previews consisting of a repeated wordnwith a transposed central bigram (e.g.,caotforcoat) and a substituted central bigram (e.g.,ceitforcoat), showing the latter to have a deleterious effect on processing wordn, thereby demonstrating that the parafoveal preview effect is at least orthographic and not purely visual. [ABSTRACT FROM AUTHOR]

With the increasing usage of in-vehicle systems, drivers have to frequently perceive and respond to messages from these in-vehicle systems. In addition, previous studies have found that the interval between the messages (arrival rate) presented to a driver becomes one of the factors affecting driver workload. To reduce driver workload, researchers on adaptive workload-management systems have found that adding extra delay time into the interval of messages can significantly reduce driver workload. However, it is unknown whether this extra delay time added by an adaptive workload-management system will increase the performance time of drivers or not. To answer this important question, using closed-form mathematical equations, the current work quantifies human performance time (total task completion time and reaction time of each task) when there are two serial processing stages in the human cognitive system. The mathematical model developed in this work provides solutions of the optimal interval of messages that generate the lowest workload without deteriorating drivers' performance time to respond to multiple messages from in-vehicle systems. This is one of a few closed-form deterministic mathematical models with analytic solutions that can predict average reaction time when there are two multiple serial stages in the cognitive system in dual tasks. With relatively simple equations, the mathematical model can still capture the major patterns of simulation results with stochastic properties and human behavioral experimental results. The mathematical equations developed in this study can be used in the design of adaptive workload-management systems and other driver assistance systems. [ABSTRACT FROM PUBLISHER]

Abstract: This study combines source analysis imaging data for early somatosensory processing and the probabilistic cytoarchitectonic maps (PCMs). Human somatosensory evoked fields (SEFs) were recorded by stimulating left and right median nerves. Filtering the recorded responses in different frequency ranges identified the most responsive frequency band. The short-latency averaged SEFs were analyzed using a single equivalent current dipole (ECD) model and magnetic field tomography (MFT). The identified foci of activity were superimposed with PCMs. Two major components of opposite polarity were prominent around 21 and 31ms. A weak component around 25ms was also identified. For the most responsive frequency band (50–150Hz) ECD and MFT revealed one focal source at the contralateral Brodmann area 3b (BA3b) at the peak of N20. The component ~25ms was localised in Brodmann area 1 (BA1) in 50–150Hz. By using ECD, focal generators around 28–30ms located initially in BA3b and 2ms later to BA1. MFT also revealed two focal sources — one in BA3b and one in BA1 for these latencies. Our results provide direct evidence that the earliest cortical response after median nerve stimulation is generated within the contralateral BA3b. BA1 activation few milliseconds later indicates a serial mode of somatosensory processing within cytoarchitectonic SI subdivisions. Analysis of non-invasive magnetoencephalography (MEG) data and the use of PCMs allow unambiguous and quantitative (probabilistic) interpretation of cytoarchitectonic identity of activated areas following median nerve stimulation, even with the simple ECD model, but only when the model fits the data extremely well. [ABSTRACT FROM AUTHOR]

A compelling account of the reading process holds that words must be encoded serially, and so recognized strictly one at a time in the order they are encountered. However, this view has been challenged recently, based on evidence showing that readers sometimes fail to notice when adjacent words appear in ungrammatical order. This is argued to show that words are actually encoded in parallel, so that multiple words are processed simultaneously and therefore might be recognized out of order. We tested this account in an experiment in Chinese with 112 skilled readers, employing methods used previously to demonstrate flexible word order processing, and display techniques that allowed or disallowed the parallel encoding of words. The results provided evidence for flexible word order processing even when words must be encoded serially. Accordingly, while word order can be processed flexibly during reading, this need not entail that words are encoded in parallel. [ABSTRACT FROM AUTHOR]

The interaction between length and lexical Status is one of the key findings used in support of models of reading aloud that postulate a serial process in the orthography-to-phonology translation (B. S. Weekes, 1997). However, proponents of parallel models argue that this effect arises in peripheral visual or articulatory processes. The authors addressed this possibility using the special characteristics of the Serbian and Japanese writing systems. Experiment 1 examined length effects in Serbian when participants were biased to interpret phonologically bivalent stimuli in the alphabet in which they are words or in the alphabet in which they are nonwords (i.e., the visual characteristics of stimuli were held constant across lexical status). Experiment 2 examined length effects in Japanese kana when words were presented in the kana script in which they usually appear or in the script in which they do not normally appear (i.e., the phonological characteristics of stimuli were held constant across lexical status). Results in both cases showed a larger length effect when stimuli were treated as nonwords and thus offered strong support to models of reading aloud that postulate a serial component. [ABSTRACT FROM AUTHOR]

Recent research has developed two eye-controlled highlighting techniques, namely, block highlight display (BHD) and single highlight display (SHD), that enhance information presentation based on a user's current gaze position. The present research aimed to investigate how these techniques facilitate mental processing of users' visual search in high information-density visual environments. In Experiment 1, 60 participants performed 3-, 6-, 9-, and 12-icon visual search tasks. The search times significantly increased as the number of icons increased with the SHD but not with the BHD. In Experiment 2, 40 participants performed a 49-icon visual search task. The search time was faster, and the fixation spatial density was lower with the BHD than with the SHD. These results suggested that the BHD supported parallel processing in the highlighted area and serial processing in the broader display area; thus, the BHD improved search performance compared to the SHD, which primarily supported serial processing. [ABSTRACT FROM AUTHOR]

Event-related potentials (ERPs) were recorded in subjects while they were matching two sequentially presented color spots. The two spots might be presented in the same position of the same color, or different colors (color conflict). They might be in different positions of the same color (position conflict), or different colors (color and position conjunction conflicts). Subjects matched the stimuli in three different sessions according to different attention tasks: attending to color, attending to position, or attending to both color and position. A negative one-peak brain potential, N270, was elicited in all the conflict conditions with amplitude enhanced in the task-relevant conflict. Two negative effects, N270 and N400, were recorded when attending to the conjunction conflicts concurrently. Visual spatial information is processed through the dorsal stream, while the feature information is processed through the ventral stream in the brain. The results suggest that all kinds of conflicts might be processed in a common system above the level of the two streams, which processes the conjunction conflict information from ventral and dorsal stream in series. [ABSTRACT FROM AUTHOR]

Abstract: How does the efficiency of attentional selection depend on the number of attended objects in a display? We measured the channel capacity (CC) of human observers during the attentional tracking of moving targets. The relation between CC and target number was used to estimate target-sampling rate. The sampling rate was halved when the number of targets was doubled, indicating that tracking was accomplished by a mechanism whose processing rate did not vary with target number. Systematically varying the dynamic parameters of the display provided inconclusive evidence for the idea that the time interval between successive samples of the same target increased with target number. These results are consistent with the hypothesis that the selection of multiple moving objects involves a limited capacity processor. [Copyright &y& Elsevier]

Determining the neuronal architecture underlying certain visual functions is of fundamental importance for understanding how sensory processing is implemented in the brain. The wealth of anatomical, physiological and biophysical data that is being currently acquired on the neocortex could be used to constrain its functional architecture. However, given the intrinsic complexity and diversity of the data, it is difficult to provide a comprehensive framework to use these data in order to characterize structure–function relationships. Here, we discuss the use of biophysically plausible models of dynamics of neuronal networks, constructed to reflect the known properties of neocortical connectivity and modularity, as a tool to bring together anatomy and physiology. We illustrate the utility and rationale of the neuro-dynamics modelling approach by considering recent studies on the relationship between functional structure of the visual cortex and its response timing, and on the cellular and network origin of neuronal oscillations in the gamma frequency range. We also critically discuss how an interaction between theory and experiments could help this approach to become directly relevant for clinical applications. [Copyright &y& Elsevier]

Segmented fluids can easily be processed in micro reactors and micro capillaries, if several boundary conditions are fulfilled. The ability of formation of highly regular segments and segment distances in combination with the ability of controlled manipulation, splitting and fusion of carrier liquid columns and single droplets opens the way to a new class of miniaturized chemical and biological operations. The subdivision of a certain reaction or a cultivation volume in a lot of aliquotes and the individual handling of the subvolumes leads to the possibility of realizing serial processes and statistical investigations by numerous highly comparable, but well separated reactor volumes. Combination of different substances, e.g. for testing of synergetic effects in drug development or catalysts screening, can be performed to large extent. The concept of “digital” reaction technology by micro fluid segments means the introduction of a digitalization principle by use of a large number of small reaction volumes handled serially in flow channels and flow-through micro devices. For the realization a set of modules including special interconnectors, T-junctions and other injector elements, transfer units and fluid resistance elements are necessary. Flow fusion modules and segment fusion modules are needed for the reorganization and recombination of serially flowing sequences of fluid segments and for the initiation of reactions by mixing of pairs and triplets of single segments. The principle can be used for quantitative chemical analyses like titration realized by use of micro fluid segments (digital micro segment titration). Micro segments could also be applied in modular synthetic chemistry, particularly in combinatorial chemistry so far as the educts and products of the single synthesis steps are compatible with liquid/liquid two phase system. The segmented flow principle is of particular interest in microbiological experiments and screening procedures. First result show the practical advantages in the highly parallelized production of monoclonal cell cultures in culture sets of very high diversity and for the cultivation of slowly growing microbial species. In addition, the possibility of producing of separated cell cultures in high density opens a series of applications in the screening and testing of drugs. [Copyright &y& Elsevier]

Micro system technology offers convenient tools for the production of handling devices for small liquid volumes which can be used in cell cultivation. Here, a modular system for the rapid generation of cell suspension aliquots is presented. The system is used to produce and analyze high numbers of well-separated culture volumes. Selected clones may be retrieved from the system. Therefore, the principle of segmented flow is applied. Portions of aqueous culture medium containing one cell or very small cell ensembles are separated from each other by a nonmiscible liquid like dodecane, tetradecane or mineral oil. In addition, the alkane separates the culture droplets from the innerside of the walls of chip channels and capillaries. This way, compatibility problems between cell wall surfaces and the chemical character of walls are excluded. The separated culture droplets are guided by micro flow transportation in different channel and chamber topologies. The whole system has the character of a serially operating cell processing system. The aliquot generation can be sped up to frequencies of about 30 Hz in each microchannel. That means, that about 105 individual cultural volumes can be produced per hour or about 2 million per day. The survival and the growth of microorganisms has been shown for model organisms as well as for organisms from a natural sample (soil). [Copyright &y& Elsevier]

To clarify the brain mechanism for multifeature stimulus comparison, subjects matched the features of two serial visual stimuli in pairs. Stimulus pairs were of four categories: C−S−, color same, shape same (match); C−S+, color same, shape different (shape mismatch); C+S−, color different, shape same (color mismatch); C+S+, color different, shape different (conjunction mismatches). Subjects matched the stimuli in three different sessions according to different attention tasks: attending to color (Ac), attending to shape (As), or attending to both color and shape (Acs). A negative one-peak brain potential, N270, was elicited in all the mismatch conditions with amplitude enhanced in the task-relevant mismatch. Negative potential with two peaks, N270 and N400, appeared when attending to the conjunction mismatches concurrently. The two serial negativities in response to attended feature conjunctions might reflect the temporal different stages for processing conjunction mismatches or conflicts. [ABSTRACT FROM AUTHOR]

To investigate the processing of noxious stimuli within the primary somatosensory cortex (SI), we recorded magnetoencephalography following noxious epidermal electrical stimulation (ES) and innocuous transcutaneous electrical stimulation (TS) applied to the dorsum of the left hand. TS activated two sources sequentially within SI: one in the posterior bank of the central sulcus and another in the crown of the postcentral gyrus, corresponding to Brodmann's areas 3b and 1, respectively. Activities from area 3b consisted of 20- and 30-ms responses. Activities from area 1 consisted of three components peaking at 26, 36 and 49 ms. ES activated one source within SI whose location and orientation were similar to those of the TS-activated area 1 source. Activities from this source consisted of three components peaking at 88, 98 and 109 ms, later by 60 ms than the corresponding TS responses. ES and TS subsequently activated a similar region in the upper bank of the sylvian fissure, corresponding to the secondary somatosensory cortex (SII). The onset latency of the SII activity following ES (109 ms) was later by 29 ms than that of the first SI response (80 ms). Likewise, the onset latency of SII activity following TS (52 ms) was later by 35 ms than that of area 1 of SI (17 ms). Therefore, our results showed that the processing of noxious and innocuous stimuli is similar with respect to the source locations and activation timings within SI and SII except that there were no detectable activations within area 3b following noxious stimulation. [ABSTRACT FROM AUTHOR]

In a study using event-related brain potentials, we show that the current characterization of the P600 component as an indicator of revision processes (reanalysis and repair) in sentence comprehension must be extended to include the recognition of syntactic ambiguity. By comparing the processing of ambiguous and unambiguous sentence constituents in German, we show that the P600 is elicited when our language processing system has syntactic alternatives at a certain item given in the input string. That the P600 is sensitive to syntactic ambiguity adds crucial evidence to current debates in psycholinguistic modelling, as the results clearly favour parallel models of syntactic processing which assume that ambiguity is recognized and costly. [Copyright &y& Elsevier]

We designed two extensions of Saslow''s well-known gap and overlap conditions that require increased voluntary effort because of the progressive elimination of target onsets and fixation point offsets, and obtained repeatable data obeying simple numerical relations. For each of the five stimulus lighting conditions, saccadic latency was measured as a function of the retinal eccentricity or displacement of the target. Latencies were fitted by a serial processing model in which the visually guided minimum tracking latency VGLmin is supplemented by two types of delay, dubbed `unlock'' and `target'', that can be either short or long (`direct'' or `indirect''), depending on the conditions. There are two findings: (1) The model has utility. The rank order of saccadic latencies for the five stimulus lighting conditions was constant across all subjects, sessions and eccentricities in the range 7.5′–6° left or right. For pooled data, and the saccadic latency plateau (1–6°), the model was also within ±3 ms of the mean latencies. (2) Latencies of tiny saccades to intrafoveolar stimulation (7.5–45′) were invariably long in all five stimulus conditions. One factor here must be the experimentally measured local prolongation of VGLmin. [Copyright &y& Elsevier]

• We examined the nature of the unique contribution of visual attention span to reading. • Visual attention span related to serial, but not discrete rapid automatized naming. • Format-specific relations were found between rapid automatized naming and reading. • Relations of visual attention span with serial and discrete reading were similar. • Visual attention span thus reflects parallel multi-element processing within words. Visual attention span (VAS) has been shown to make a unique contribution to reading skills over and above phonological awareness and rapid automatized naming (RAN). In the current study, we examined the nature of this unique relationship. In particular, we tested whether VAS reflects the retrieval of a verbal code, serial processing, or parallel multi-element processing. To this end, we presented 180 third graders with tasks for VAS, discrete RAN, and serial RAN as well as serial and discrete reading of short words, pseudowords, and long words. VAS was found to correlate with serial RAN but not with discrete RAN. More important, similar relations were found for VAS with serial and discrete reading, which clearly differed from the format-specific relations between RAN and reading. Together, these findings suggest that VAS and serial RAN are related but are associated with reading for different reasons. Serial RAN appears to reflect serial interword reading processes, whereas the unique contribution of VAS mainly involves the parallel processing of orthographic units within words. [ABSTRACT FROM AUTHOR]

It has long been known that cues can be used to improve performance on memory recall tasks. There is evidence to suggest additional cues provide further benefit, presumably by narrowing the search space. Problems that require integration of two or more cues, alternately referred to as memory intersections or multiply constrained memory problems, could be approached using several strategies, namely serial or parallel consideration of cues. The type of strategy implicated is essential information for the development of theories of memory, yet evidence to date has been inconclusive. Using a novel application of the powerful Systems Factorial Technology (Townsend & Nozawa, 1995) we find strong evidence that participants use two cues in parallel in free recall tasks - a finding that contradicts two recent publications in this area. We then provide evidence from a related recognition task showing that while most participants also use a parallel strategy in that paradigm, a reliable subset of participants used a serial strategy. Our findings suggest a theoretically meaningful distinction between participants strategies in recall and recognition based intersection memory tasks, and also highlight the importance of tightly controlled methodological and analytic frameworks to overcome issues of serial/parallel model mimicry. [ABSTRACT FROM AUTHOR]