Parallel Distributed Processing Model Research Articles

Design and Simulation of a Hierarchical Parallel Distributed Processing Model for Orientation Selection Based on Primary Visual Cortex.

The study of the human visual system not only helps to understand the mechanism of the visual system but also helps to develop visual aid systems to help the visually impaired. As the systematic study of neural signal processing mechanisms in early biological vision continues, the hierarchical structure of the visual system is gradually being dissected, bringing the possibility of building brain-like computational models from a bionic perspective. In this paper, we follow the objective facts of neurobiology and propose a parallel distributed processing computational model of primary visual cortex orientation selection with reference to the complex process of visual signal processing and transmission between the retina to the primary visual cortex, the hierarchical receptive field structure between cells in each layer, and the very fine-grained parallel distributed characteristics of cortical visual computation, which allow for high speed and efficiency. We approach the design from a brain-like chip perspective, map our network model on the field programmable gate array (FPGA), and perform simulation experiments. The results verify the possibility of implementing our proposed model with programmable devices, which can be applied to small wearable devices with low power consumption and low latency.

Inflectional Changes of Double Marked Form: Evidence from a Corpus Study of English Verbal System

It is assumed languages of human beings are directed by rules; however, these rules have certain exceptions in the form of irregularities. A double-marked form in which the regular rule is added to an irregular form has been attested in languages of human beings and is considered as a type of irregularization in the morphological processing. It has been claimed that there is a correlation between this type of irregularization process and high word frequencies. The real rate and nature of these double-marked forms have rarely been documented. On the basis of data from the new linguistic corpus (WebCorp) which allows us to make refined searches given its wider range of searching possibilities, this paper investigates whether there is a correlation between these irregularization processes in the English verbal system and word frequency with the aim of addressing the research questions: Is there a relationship between irregularization with the type of double-marked forms and word frequency in current English? If so, are irregular verbs with high frequency irregularized more often than the ones with low frequency? To do so, word frequencies of 488 irregular verbs in the past and perfect were collected from the selected corpus. Then, word frequencies of their corresponding double-marked forms in both forms were collected from the same corpus. Descriptive and statistical analyses were conducted to test the importance of the difference in the results. The results of the data in this study suggested that there is a correlation between high word frequency and these irregularization processes. By considering the current irregularization processes in English verbal system, this study makes an attempt to provide an introductory source of analytical research of how linguistic information is mentally processed and represented by the human language faculty. Reference: Albright, A., & Hayes, B. (2003). Rules vs. analogy in English past tenses: A computational/experimental study. Cognition, 90(2), 119–161. Bergh, M., Van, D., & Straaten, J. (1994). Historical and future models of economic development and natural environment. Chapter 8 in Van den Bergh and van der Straaten (eds.), Toward Sustainable Development: Concepts, Methods and Policy, Island Publ., Washington D.C., pp. 209- 234. Bybee, J. (1995). Regular morphology and the lexicon. Language and Cognitive Processes, 10(5), 425–455. Chomsky, N., & Halle, M. (1968). The sound pattern of English. New York : Harper and Row. Chialant, D. & Caramazza, A. (1995). Where is morphology and how is it processed? The case of written word recognition. In L.B. Feldman (Ed). Morphological aspects of language processing. (pp. 55–76). Hillsdale, NJ: Lawrence Erlbaum Associates. Clahsen, H. (1999). Lexical entries and rules of language: A multidisciplinary study of German inflection. Behavioral and Brain Sciences, 22(6), 991–1013. Retrieved from https://www.cambridge.org/core/journals/behavioral-and-brain-sciences/article/lexical-entries-and-rules-of-language-a-multidisciplinary-study-of-german-inflection/6608FA17C363432CF92BCE3322541897 Crystal, D. (2004). Language and the Internet. Cambridge: Cambridge University Press. https://doi.org/10.1017/CBO9780511487002 Fertig, D. (1998a), ‘Suppletion, Natural Morphology, and Diagrammaticity’. Linguistics 36, 1065–91. Fertig, D. (2013). Analogy and morphological change. Edinburgh University Press. 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Implementations are not conceptualizations: Revising the verb learning model. Cognition, 40(1–2), 121–157. https://doi.org/10.1016/0010-0277(91)90048-9 Michel, J.-B., Shen, Y. K., Aiden, A. P., Veres, A., Gray, M. K., Pickett, J. P., … Orwant, J. (2011). Quantitative analysis of culture using millions of digitized books. Science, 331(6014), 176–182. Nübling, D. (2000), Prinzipien der Irregularisierung, Tübingen: Niemeyer. Peters, P. (2009). Comparative studies in Australian and New Zealand English: grammar and beyond. Macquarie University. Pinker, S. (1999). Words and rules: The ingredients in language. London: Weidenfeld & Nicolson. Pinker, S., & Prince, A. (1988). On language and connectionism: Analysis of a parallel distributed processing model of language acquisition. Cognition, 28(1), 73–193. https://doi.org/10.1016/0010-0277(88)90032-7 Pinker, S., & Ullman, M. T. (2002). The past and future of the past tense. Trends in Cognitive Sciences, 6(11), 456–463. Rumelhart, D. E., & McClelland, J. L. (1986). On learning the past tenses of English verbs. Explorations in the Microstructure of Cognition, 2. Schreuder, R., & Baayen, R. H. (1995). Modeling morphological processing. In L. B. Feldman (Ed.), Morphological aspects of language processing (p. 131–154). Lawrence Erlbaum Associates, Inc. Xu, F., & Pinker, S. (1995). Weird past tense forms. Journal of Child Language, 22(3), 531–556. https://doi.org/10.1017/S0305000900009946 Yang, C. (2002). Knowledge and learning in natural language. Oxford University Press on Demand.

The binding guided by attention: Toward an integrated approach on the investigations of conflict adaptation

<p indent=0mm>In the everyday life, internal goals guide us to focus on task-relevant information but inhibit task-irrelevant information that however could not be completely filtered out. Here, cognitive control is required to drive the attention in accordance with internal goals. As an important phenomenon in the field of cognitive control, conflict adaptation refers to the adaptability of cognitive control in goal-guided behaviors, which is of great significance for individuals to adapt to ever-changing environments. In the lab, conflict adaptation is indexed by a reduced conflict after conflict trials (i.e., Trial <italic>n</italic>–1 is incongruent stimulus) compared with after non-conflict trials (i.e., Trial <italic>n</italic>–1 is congruent stimulus). In order to explain this important effect, researchers have proposed a number of accounts, which could be classified into two kinds of perspectives: Attention-based control accounts and memory-based learning accounts. The former includes the well-known conflict monitoring theory, the activation-suppression theory, the negative affective theory, and the expectancy theory. Whereas, the feature-integration theory, the contingency learning hypothesis, and the temporal learning hypothesis belong to the latter. In short, the control accounts emphasize that attentional resources adjustment leads to conflict adaptation through allocating more resources to the target dimension while allocating fewer resources to the distractor dimension. On the other hand, the learning accounts propose that the binding and unbinding of memories between stimulus and responses result in conflict adaptation. Due to their different research focuses, however, the previous studies have discussed the two accounts separately, which is not conducive to the investigation and understanding of the full profiles of conflict adaptation. From our perspective, conflict adaptation in essence is a goal-directed adjustment process. Meanwhile, it is also a phenomenon of learning. Accordingly, in the present comprehensive review, we proposed a hypothesis of the binding guided by attention, which combines the control accounts and the learning accounts. Specifically, conflict adaptation does not only need to guide the allocation of attention resources through task demand, but also needs to enhance the memory representation of “stimulus-response” mapping through binding learning. The integration of the two processes should ultimately promote the occurrence of conflict adaptation. In fact, our hypothesis explains conflict adaptation by combining the Biased Competition model with the Parallel Distributed Processing model. Firstly, the Biased Competition model posits that top-down selective attention enhances neuronal activities that respond to target features and inhibits response-selective neuronal activities of distractor features. Thus, the competition between neurons is biased towards target characteristics. Secondly, the Parallel Distributed Processing model postulates that different stimulus dimensions (e.g., colors and spatial locations) are processed in parallel in different channels that however can activate the same response system, and selective attention can change the processing priority of different stimulus dimensions. To conclude, by integrating the control accounts and the learning accounts, the current hypothesis provides a comprehensive and interpretable mechanism to address conflict adaptation. To be more specific, this hypothesis proposes that conflict adaptation is ultimately generated through binding learning (i.e., the Hebbian learning) with the Parallel Distributed Processing model as the underlying mechanism. More importantly, the binding learning must be guided by the top-down attention-based control mechanism, which is achieved through the Biased Competition model. In summary, the attention-guided binding learning hypothesis provides an integrated reference frame for an in-depth understanding of the internal mechanism of conflict adaptation.

Neuronal Congruency Signals in Macaque Frontal Cortex

Conflict paradigms, such as the Stroop task, are frequently used to investigate cognitive control, an essential cognitive process for goal-directed behavior. Congruency effects are behavioral signatures of such paradigms. However, the neuronal mechanisms underlying such congruency effects and how they are represented in the brain are poorly understood. We recorded single unit activity in monkey frontal cortex using a novel rule-based attention-conflict paradigm and discovered a neuronal congruency representation which was composed of a concurrent facilitation effect in task-relevant neurons and an interference effect in task-irrelevant neurons. We also found that response-conflicts are not necessary for evoking behavioral congruency effects. We propose a simple parallel distributed processing model allowing the concomitant neuronal facilitation and interference signals to develop. Such neuronal congruency signals explain behavioral congruency effects in general, as well as previous fMRI and EEG results in various conflict paradigms.

Phonological Treatment Approaches for Spoken Word Production in Aphasia.

This article provides an overview of phonological treatment approaches for anomia in individuals with aphasia. The role of phonology in language processing, as well as the impact of phonological impairment on communication is initially discussed. Then, traditional phonologically based treatment approaches, including phonological, orthographic, indirect, guided, and mixed cueing methods, are described. Collectively, these cueing treatment approaches aim to facilitate word retrieval by stimulating residual phonological abilities. An alternative treatment approach, phonomotor treatment, is also examined. Phonomotor treatment aims to rebuild sublexical, phonological sequence knowledge and phonological awareness as a means to strengthen lexical processing and whole-word naming. This treatment is supported by a parallel-distributed processing model of phonology and therefore promotes multimodal training of individual phonemes and phoneme sequences in an effort to enhance the neural connectivity supporting underlying phonological processing mechanisms. The article concludes with suggestions for clinical application and implementation.

Understanding the Reading Process: One Path to Strengthening Classroom Instruction

Knowing how to provide effective literacy instruction is important for all educators, but it is critically important for urban educators. This article is built on the assumption that deepening urban educators’ understanding of the reading process will better equip them to facilitate students’ reading development, and to diagnose and intervene if reading difficulties are discovered. Based on that belief, a discussion of a highly regarded reading model, the Parallel Distributed Processing Model (PDPM), is presented. Classroom implications of the reading model are also discussed. Overall, it is hoped that understanding the reading process through the lens of PDPM will help urban educators promote reading success for all students.

An Extension of a Parallel-Distributed Processing Framework of Reading Aloud in Japanese: Human Nonword Reading Accuracy Does Not Require a Sequential Mechanism.

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.

The Phonomotor Approach to Treating Phonological-Based Language Deficits in People With Aphasia

The phonomotor treatment program for treating word-retrieval deficits among people with aphasia is inspired by a parallel distributed processing model of lexical processing and is focused at the level of individual phonemes and phoneme sequences. Because verbal production of words involves the translation of a lexical-semantic representation into phonological representations, training the repertoire of phonological sequences should enable individuals with anomia to regain the ability to learn words and sequences, generalize to linguistic items not trained, and continue growth following treatment termination. The development and refinement of the phonomotor treatment program, which began in 2000, have followed the 5-phase model for communication disorders and sciences framework outlined by R. Robey (2004). To date, there have been 8 published articles on the phonomotor treatment program. A large-scale randomized trial comparing phonomotor with standard of care for word-retrieval deficits is underway. The goal of this article is to review the theoretical framework, treatment procedures, current evidence, and future directions of the phonomotor protocol.

Why do some neurons in cortex respond to information in a selective manner? Insights from artificial neural networks

Why do some neurons in hippocampus and cortex respond to information in a highly selective manner? It has been hypothesized that neurons in hippocampus encode information in a highly selective manner in order to support fast learning without catastrophic interference, and that neurons in cortex encode information in a highly selective manner in order to co-activate multiple items in short-term memory (STM) without suffering a superposition catastrophe. However, the latter hypothesis is at odds with the widespread view that neural coding in the cortex is highly distributed in order to support generalization. We report a series of simulations that characterize the conditions in which recurrent Parallel Distributed Processing (PDP) models of immediate serial can recall novel words. We found that these models learned localist codes when they succeeded in generalizing to novel words. That is, just as fast learning may explain selective coding in hippocampus, STM and generalization may help explain the existence of selective codes in cortex.

Connectionists Approaches to Language Processing and Acquisition

The degree to which the behaviour of parallel distributed processing (PDP) models approximates children's acquisition of inflectional morphology has recently been highlighted in discussion of the applicability of PDP to the study of human cognition and language. In this paper, an attempt is made to examine many of the limitations of the Rumelhart and McClelland model and adopt an empirical, comparative approach to the analysis of learning....

Can intensive phonomotor therapy modify accent? A phase I study

A variety of accent modification approaches exist for non-native English speakers. The training program developed for this study, phonomotor treatment, is based on a parallel distributed processing model of phonology and was hypothesized to modify accent via improved sound production in a non-native English speaker. The participant was a 20-year-old native Wuhan and Mandarin Chinese speaker. In the context of a single-subject repeated probe design, he received probes prior to, during, and immediately following training. Training was intensive and delivered for 20 hours over 2 weeks. Post-training results revealed statistically significant improvements in trained phoneme production in isolation and reduced listener effort at the sentence level. Generalization results were limited, suggesting that future participants may benefit from an increased training period and additional program development. Data gathered from this study may also help to inform the development of subsequent trials of the same program.

Thresholds of visibility for masked lexical, non-lexical, and non-linguistic items in aphasia

Thresholds of visibility for masked lexical, non-lexical, and non-linguistic items in aphasia

Simulating Cooperative Interactions to Investigate the Neural Correlates of Joint Attention

Event Abstract Back to Event Simulating Cooperative Interactions to Investigate the Neural Correlates of Joint Attention Nathan Caruana1*, Alexandra Woolgar1 and Jon Brock1 1 ARC Centre of Excellence in Cognition and its Disorders , Cognitive Science, Australia Joint attention is a fundamental aspect of social cognition, enabling effective intersubjective experiences. However, due to lacking ecological measures, we currently know little about its neural representation, or how this diverges in developmental disorders such as autism. Joint attention is conceptualised as involving two distinct functions. Responding to joint attention (RJA) involves converging with someone else's focus of attention. Initiating joint attention (IJA), involves guiding others to converge with one's own attentional focus. The Parallel Distributed Processing (PDP) model accounts for the overlapping function, and developmental divergence of RJA and IJA. Consistent with this model, we anticipated that sources of activation associated with RJA and IJA would reflect partially independent regions, existing in a distally distributed, posterior and anterior network. Inspired by the second person perspective (2PP) approach to social cognition research, we developed a co-operative, virtual reality task for the acquisition of fMRI and MEG data. Using eye-tracking techniques, subjects interacted with an onscreen avatar, which responded contingently to their gaze. Subjects completed the task under the impression that they were interacting with a confederate, outside the scanner, who was controlling the avatar's eye movements. Our analyses have focused on comparing neural activation during the execution of RJA and IJA behaviour, as well as during conditions where participants complete the same task 'alone'. Our fMRI univariate whole brain analyses revealed temporoparietal and anterior networks associated with gaze detection, attention orienting and mentalising processes. An MEG case study, using the same task and a novel saccade-related beamforming analysis was also conducted to localise activation associated with preparing saccades for the execution of RJA and IJA. These data and critical issues in designing interactive paradigms will be discussed. Keywords: fMRI, MEG, eye tracking, joint attention, virtual reality Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Emotional and Social Processes Citation: Caruana N, Woolgar A and Brock J (2015). Simulating Cooperative Interactions to Investigate the Neural Correlates of Joint Attention. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00046 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Mr. Nathan Caruana, ARC Centre of Excellence in Cognition and its Disorders, Cognitive Science, North Ryde, Australia, nathan.caruana@mq.edu.au Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Nathan Caruana Alexandra Woolgar Jon Brock Google Nathan Caruana Alexandra Woolgar Jon Brock Google Scholar Nathan Caruana Alexandra Woolgar Jon Brock PubMed Nathan Caruana Alexandra Woolgar Jon Brock Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

A frontotemporoparietal network common to initiating and responding to joint attention bids

Joint attention is a fundamental cognitive ability that supports daily interpersonal relationships and communication. The Parallel Distributed Processing model (PDPM) postulates that responding to (RJA) and initiating (IJA) joint attention are predominantly supported by posterior-parietal and frontal regions respectively. It also argues that these neural networks integrate during development, supporting the parallel processes of self- and other-attention representation during interactions. However, direct evidence for the PDPM is limited due to a lack of ecologically valid experimental paradigms that can capture both RJA and IJA. Building on existing interactive approaches, we developed a virtual reality paradigm where participants engaged in an online interaction to complete a cooperative task. By including tightly controlled baseline conditions to remove activity associated with non-social task demands, we were able to directly contrast the neural correlates of RJA and IJA to determine whether these processes are supported by common brain regions. Both RJA and IJA activated broad frontotemporoparietal networks. Critically, a conjunction analysis identified that a subset of these regions were common to both RJA and IJA. This right-lateralised network included the dorsal portion of the middle frontal gyrus (MFG), inferior frontal gyrus (IFG), middle temporal gyrus (MTG), precentral gyrus, posterior superior temporal sulcus (pSTS), temporoparietal junction (TPJ) and precuneus. Additional activation was observed in this network for IJA relative to RJA at MFG, IFG, TPJ and precuneus. This is the first imaging study to directly investigate the neural correlates common to RJA and IJA engagement, and thus support the assumption that a broad integrated network underlies the parallel aspects of both initiating and responding to joint attention.

Parallel Distributed Processing at 25: further explorations in the microstructure of cognition.

This paper introduces a special issue of Cognitive Science initiated on the 25th anniversary of the publication of Parallel Distributed Processing (PDP), a two-volume work that introduced the use of neural network models as vehicles for understanding cognition. The collection surveys the core commitments of the PDP framework, the key issues the framework has addressed, and the debates the framework has spawned, and presents viewpoints on the current status of these issues. The articles focus on both historical roots and contemporary developments in learning, optimality theory, perception, memory, language, conceptual knowledge, cognitive control, and consciousness. Here we consider the approach more generally, reviewing the original motivations, the resulting framework, and the central tenets of the underlying theory. We then evaluate the impact of PDP both on the field at large and within specific subdomains of cognitive science and consider the current role of PDP models within the broader landscape of contemporary theoretical frameworks in cognitive science. Looking to the future, we consider the implications for cognitive science of the recent success of machine learning systems called "deep networks"-systems that build on key ideas presented in the PDP volumes.

PSPs and ERPs: Applying the dynamics of post-synaptic potentials to individual units in simulation of temporally extended Event-Related Potential reading data

The Parallel Distributed Processing (PDP) framework is built on neural-style computation, and is thus well-suited for simulating the neural implementation of cognition. However, relatively little cognitive modeling work has concerned neural measures, instead focusing on behavior. Here, we extend a PDP model of reading-related components in the Event-Related Potential (ERP) to simulation of the N400 repetition effect. We accomplish this by incorporating the dynamics of cortical post-synaptic potentials—the source of the ERP signal—into the model. Simulations demonstrate that application of these dynamics is critical for model elicitation of repetition effects in the time and frequency domains. We conclude that by advancing a neurocomputational understanding of repetition effects, we are able to posit an interpretation of their source that is both explicitly specified and mechanistically different from the well-accepted cognitive one.

Not lost in translation: generalization of the primary systems hypothesis to Japanese-specific language processes.

The emergentist-connectionist approach assumes that language processing reflects interaction between primary neural systems (Primary Systems Hypothesis). This idea offers an overarching framework that generalizes to various kinds of (English) language and nonverbal cognitive activities. The current study advances this approach with respect to language in two new and important ways. The first is the provision of a neuroanatomically constrained implementation of the theory. The second is a test of its ability to generalize to a language other than English (in this case Japanese) and, in particular, to a feature of that language (pitch accent) for which there is no English equivalent. A corpus analysis revealed the presence and distribution of typical and atypical accent forms in Japanese vocabulary, forming a quasiregular domain. Consequently, according to the Primary Systems Hypothesis, there should be a greater semantic impact on the processing of words with an atypical pitch accent. In turn, when word meaning is intrinsically less rich (e.g., abstract words), speakers should be prone to regularization errors of pitch accent. We explored these semantic-phonological interactions, first, in a neuroanatomically constrained, parallel-distributed processing model of spoken language processing. This model captured the accent typicality effect observed in nonword repetition in Japanese adults and children and exhibited the predicted semantic impact on repetition of words with atypical accent patterns. Second, also as predicted, in word repetition and immediate serial recall of spoken words, human participants exhibited reduced pitch-accent accuracy and/or slower RT for low imageability words with atypical accent patterns, and they generated accent errors reflecting the more typical accent patterns found in Japanese.

Phonological coding during reading.

The exact role that phonological coding (the recoding of written, orthographic information into a sound based code) plays during silent reading has been extensively studied for more than a century. Despite the large body of research surrounding the topic, varying theories as to the time course and function of this recoding still exist. The present review synthesizes this body of research, addressing the topics of time course and function in tandem. The varying theories surrounding the function of phonological coding (e.g., that phonological codes aid lexical access, that phonological codes aid comprehension and bolster short-term memory, or that phonological codes are largely epiphenomenal in skilled readers) are first outlined, and the time courses that each maps onto (e.g., that phonological codes come online early [prelexical] or that phonological codes come online late [postlexical]) are discussed. Next the research relevant to each of these proposed functions is reviewed, discussing the varying methodologies that have been used to investigate phonological coding (e.g., response time methods, reading while eye-tracking or recording EEG and MEG, concurrent articulation) and highlighting the advantages and limitations of each with respect to the study of phonological coding. In response to the view that phonological coding is largely epiphenomenal in skilled readers, research on the use of phonological codes in prelingually, profoundly deaf readers is reviewed. Finally, implications for current models of word identification (activation-verification model, Van Orden, 1987; dual-route model, e.g., M. Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001; parallel distributed processing model, Seidenberg & McClelland, 1989) are discussed.

The Emergence of Mind: Personal Knowledge and Connectionism

The Emergence of Mind: Personal Knowledge and Connectionism

Computational modeling of the negative priming effect based on inhibition patterns and working memory.

Negative priming (NP), slowing down of the response for target stimuli that have been previously exposed, but ignored, has been reported in multiple psychological paradigms including the Stroop task. Although NP likely results from the interplay of selective attention, episodic memory retrieval, working memory, and inhibition mechanisms, a comprehensive theoretical account of NP is currently unavailable. This lacuna may result from the complexity of stimuli combinations in NP. Thus, we aimed to investigate the presence of different degrees of the NP effect according to prime-probe combinations within a classic Stroop task. We recorded reaction times (RTs) from 66 healthy participants during Stroop task performance and examined three different NP subtypes, defined according to the type of the Stroop probe in prime-probe pairs. Our findings show significant RT differences among NP subtypes that are putatively due to the presence of differential disinhibition, i.e., release from inhibition. Among the several potential origins for differential subtypes of NP, we investigated the involvement of selective attention and/or working memory using a parallel distributed processing (PDP) model (employing selective attention only) and a modified PDP model with working memory (PDP-WM, employing both selective attention and working memory). Our findings demonstrate that, unlike the conventional PDP model, the PDP-WM successfully simulates different levels of NP effects that closely follow the behavioral data. This outcome suggests that working memory engages in the re-accumulation of the evidence for target response and induces differential NP effects. Our computational model complements earlier efforts and may pave the road to further insights into an integrated theoretical account of complex NP effects.