200 results on '"Stocco, Andrea"'
Search Results
152. Automated generation of visual web tests from DOM-based web tests
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Leotta, Maurizio, primary, Stocco, Andrea, additional, Ricca, Filippo, additional, and Tonella, Paolo, additional
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- 2015
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153. Using Multi-Locators to Increase the Robustness of Web Test Cases
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Leotta, Maurizio, primary, Stocco, Andrea, additional, Ricca, Filippo, additional, and Tonella, Paolo, additional
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- 2015
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154. The Role of the Basal Ganglia– Anterior Prefrontal Circuit as a Biological Instruction Interpreter
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Stocco, Andrea, Lebiere, Christian, O'Reilly, Randall C., and Anderson, John R.
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FOS: Psychology ,170199 Psychology not elsewhere classified - Abstract
Intelligent and versatile behavior requires the capability of adapting to novel and unanticipated situations. When facing novel and unexpected tasks, a fast and general solution consists in creating new declarative task representations, and subsequently acting upon them. Although this mechanism seems straightforward in general terms, it poses significant difficulties to be implemented in a biological model, and the exact neural substrates of this process are still unknown. Based on the analysis of two different computational models, we hypothesized that the brain circuit for interpreting instructions would comprise the aPFC (holding dependencies among specialized cortical areas) and the basal ganglia (orchestrating the exchange of information among regions). To verify this hypothesis, we designed and ran an fMRI experiment where participants had to perform changing tasks that consisted of different combinations of atomic cognitive operations. Both models and experimental data suggest that the aPFC is critical in representing abstract knowledge that reflects planned cognitive operations. This is consistent with the late appearance of aPFC in the evolution of the human brain, and its role in enabling human intelligence and culture. On the other hand, results and simulations show that the effect of this cortical region is made possible by the contribution of the basal ganglia circuit, which works as a general-purpose interpreter of declarative knowledge.
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- 2010
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155. Studio dell'interazione della 'generazione distribuita' con possibili futuri assetti della rete di distribuzione
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Stocco, Andrea
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Generazione distribuita, FACTS, isola intenzionale,riconfigurazione della rete ,Settore ING-IND/33 - Sistemi Elettrici per L'Energia ,FACTS ,Generazione distribuita ,isola intenzionale ,riconfigurazione della rete - Published
- 2009
156. Farmaci oncologici e prodotti erboristici in pazienti in cura presso l'Istituto Oncologico Veneto: indagine preliminare sulle potenziali interazioni
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Giron, MARIA CECILIA, Stocco, Andrea, Bin, Anna, Zoppellaro, Chiara, Gallo, U., and Palozzo, A.
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- 2009
157. Endogenous Control in Algebraic Problem Solving: An fMRI Study
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Stocco, Andrea and Anderson, John R.
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FOS: Psychology ,170199 Psychology not elsewhere classified - Abstract
Department of Psychology
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- 2007
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158. Formal Analysis of Damasio's Theory on Core Consciousness
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Bosse, T., Jonker, C.M., Treur, J., Fum, Danilo, Missier, Fabio Del, Stocco, Andrea, Artificial intelligence, and Social AI
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- 2006
159. Farmaci e prodotti naturali-nutriceutici in una popolazione sottoposta a visita anestesiologica: indagine osservazionale sull'impiego e sulle potenziali interazioni
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Giron, MARIA CECILIA, Stocco, Andrea, Bin, Anna, Gallo, U., Bano, F., Meneghetti, F., Carniel, L., Ragazzi, M., Grion, A. M., Gaion, ROSA MARIA, and Ori, Carlo
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- 2006
160. L'INFLUSSO DEI MARCATORI SOMATICI SUI PROCESSI COGNITIVI: EVIDENZE COMPUTAZIONALI E SPERIMENTALI
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STOCCO, ANDREA, FUM, DANILO, and CAUDEK, CORRADO
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PSICOLOGIA - Abstract
2003/2004 L'influsso delle emozioni sulla cognizione centrale è stato ampiamente documentato nelle neuroscienze cognitive. La principale spiegazione al riguardo è la cosiddetta ipotesi del marcatore somatico (Damasio, 1994; 1996), che estende la cosiddetta teoria di James-Lange sull'origine somatica delle emozioni. Secondo D amasi o ( 1994 ), le emozioni nascono dalla percezione dei mutamenti degli stati corporei che costituiscono le reazioni primarie agli stimoli emotigeni. Queste reazioni rimangono poi associate alle rappresentazioni degli stimoli stessi, diventandone marcatori somatici. Questi marcatori possono poi venire riattivati in presenza di situazioni simili a quelle che li hanno originati. La maggior parte delle conferme di questa congettura, come anche alcuni risultati ad essa contrari, proviene da una serie di esperimenti condotti con un paradigma di decisione noto come Gambling Task (Bechara, Damasio, Tranel & Anderson, 1994). In questo compito, i partecipanti devono compiere delle scelte ripetute da un insieme di quattro mazzi di carte. Ogni scelta porta ad una vincita certa, la cui grandezza dipende dal mazzo. In maniera imprevedibile e stocastica, alcune vincite possono essere seguite da perdite monetarie più o meno intense. Le perdite sono predisposte strategicamente, in modo che i mazzi associati alle vincite immediate maggiori siano anche quelli che, in virtù di perdite superiori, sono più svantaggiosi nel lungo periodo. Bechara et al ( 1994) hanno mostrato che, mentre i partecipanti san1 finiscono per scegliere dai mazzi più vantaggiosi, a dispetto delle loro minori vincite immediate, i pazienti con lesioni orbitofrontali perseverano in una condotta svantaggiosa da punto di vista razionale. L'ipotesi del marcatore somatico spiega la prestazione dei partecipanti normali e di pazienti ipotizzando (l) che la parte orbitofrontale della corteccia sia necessaria all'acquisizione dei marcatori e. che (2) questi svolgano un ruolo implicito nel guidare il comportamento delle persone. A riprova di quest'ultimo assunto, Bechara et al. (1997) hanno mostrato che alcune risposte fisiologiche, interpretate come indici dell'attività dei marcatori somatici, si manifestano nei partecipanti sani prima dell'esecuzione di scelte svantaggiose, e prima che gli individui diano prova di possedere conoscenze esplicite della strategia da adottare. Per analizzare l'ipotesi del marcatore somatico è utile dividerla in due componenti. La prima è una spiegazione dell'origine delle emozioni a partire dalle rappresentazioni somatiche, e costituisce una versione moderna della teoria di James (1884). La seconda concerne il modo in cui emozione e processi cognitivi interagiscono, con particolare riguardo al supposto ruolo implicito (e dunque inconscio) svolto dai marcatori, e alla specifica funzione svolta dalla parte orbitofrontale della corteccia. Quest'ultima componente non riesce a rendere conto dei risultati degli esperimenti di Tomb, Hauser, Deldin & Caramazza (2002) e di Maia & McClelland (2004) che, a differenza di quanto postulato nell'ipotesi di Damasio (1994), hanno mostrato come le prestazioni dei partecipanti normali nel Gambling Task dipendano più dalle conoscenze esplicite del compito che essi hanno acquisito, che dalla supposta azione implicita dei marcatori somatici. Tutti questi risultati possono essere spiegati ricorrendo ad una revisione della teoria del marcatore somatico. Ho ipotizzato che il ruolo della corteccia orbitofrontale fosse quello di creare associazioni contestuali tra la rappresentazione delle azioni e le loro conseguenze e, soprattutto, che questa maggiore associazione faciliti il recupero automatico e spontaneo di informazioni su eventuali esiti negativi. L'effetto delle emozioni si manifesterebbe, quindi, senza alcun ricorso alla cognizione implicita. Al contrario, esso faciliterebbe la rappresentazione esplicita di eventuali esiti negativi, rendendone più rapida l'elaborazione e l'integrazione in strategie di decisione. Partendo da questa ipotesi di lavoro, ho realizzato un modello computazionale funzionale - implementato nell'architettura cognitiva ACT-R (Anderson & Lebiere, 1998) - che permette di spiegare in maniera estensiva le prestazioni ottenute nel Gambling Task sia dai partecipanti sani, sia da pazienti con diversi tipi di lesione. Ho paragonato i risultati delle simulazioni con i dati comportamentali riportati In letteratura, mostrando come essi siano qualitativamente e quantitativamente simili. In particolare, il modello permette di simulare la prestazione dei partecipanti sani e dei pazienti orbitofrontali (Bechara et al., 1994), dei pazienti con lesioni all'amigdala (Bechara, Damasio, Damasio & Lee, 1999) e, infine dei pazienti con lesioni alla parte dorsolaterale della corteccia prefrontale (Bechara, Damasio, Tranel & Anderson, 1998). In quest'ultimo caso, il modello che ho realizzato permette di riprodurre la doppia dissociazione tra prestazioni in compiti di memoria di lavoro e prestazioni nel Gambling Task che si osserva tra tali pazienti e quelli affetti da lesioni orbitofrontali. Infine, la funzione della corteccia orbitofrontale che il modello sottende è compatibile anche con i risultati sperimentali ottenuti da Camille et al. (2004) in un diverso compito di scelta, dove veniva evidenziata una specifica insensibilità dei pazienti orbitofrontali a provare sentimenti di rammarico, a fronte di reazioni normali a perdite e vincite. Nell'ultima parte della tesi, ho messo a confronto le differenti implicazioni del modello proposto e dell'ipotesi del marcatore somatico in due esperimenti condotti su partecipanti sani. Il primo esperimento permette di determinare se il contributo dei marcatori somatici nei compiti di scelta si manifesti durante la codifica degli esiti delle scelte intraprese, oppure nel processo di recupero degli esiti che si suppone avvenire durante la fase di scelta. Il modello prevede che la fase critica sia quella di codifica, e che, una volta codificate e opportunamente associate, il recupero delle informazioni sia pressoché automatico, almeno in presenza degli indizi contestuali opportuni. Questa previsione è confermata dai risultati dell'esperimento, in cui si osserva come un compito interferente influisca negativamente sulla codifica, ma non abbia effetti significativi sui processi di recupero. Anche le latenze dei partecipanti si conformano alle previsioni del modello, risultando minori in seguono ad una peggiore codifica. Il secondo esperimento permette di analizzare, tramite una procedura di dissociazione, il decorso temporale del diverso impatto delle emozioni sulla cognizione implicita ed esplicita. I risultati confermano quanto già affermato da Maia & McClelland (2004 ), vale a dire che le conoscenze acquisite dai partecipanti sono di natura esplicita, in netto disaccordo con quanto ipotizzato da Bechara et al. (1997). Tuttavia, un'analisi più sensibile ha messo in luce una significativa tendenza dei partecipanti a perseverare sui mazzi considerati vantaggiosi -tendenza che sfugge al controllo volontario. L'esistenza di questa propensione implicita è in contrasto con quanto sostenuto da Maia & McClelland (2004). È invece compatibile (e, anzi, ne costituisce una previsione) con l'ipotesi che ha ispirato il modello, vale a dire l'esistenza di una fase automatica di recupero delle conoscenze, influenzata dalle associazioni in precedenza create dalla corteccia orbitofrontale. L'ipotesi del marcatore somatico è in conflitto con alcuni risultati sperimentali, ma è possibile rivederla in modo da renderla compatibile con essi. A differenza di quanto postulato da Bechara et al. (1997), ho ipotizzato che le tracce emotive codificate sotto forma di marcatori somatici non agiscono implicitamente, ma, anzi, permettono l'elaborazione cosciente delle informazioni. Questa modifica della teoria è legata ad una revisione del ruolo della corteccia orbitofrontale, e permette anche di specificare in maggior dettaglio il processo per cui le emozioni influenzano la cognizione, relegando i processi impliciti alla fase di recupero degli esiti precedente. La congruenza di questa nuova ipotesi con i dati sperimentali già acquisiti è stata sondata per mezzo di simulazioni al calcolatore, mentre alcune sue conseguenze sono state testate e confermate sperimentalmente. XVII Ciclo 1976 Versione digitalizzata della tesi di dottorato cartacea.
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- 2005
161. A Direct Brain-to-Brain Interface in Humans
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Rao, Rajesh P. N., primary, Stocco, Andrea, additional, Bryan, Matthew, additional, Sarma, Devapratim, additional, Youngquist, Tiffany M., additional, Wu, Joseph, additional, and Prat, Chantel S., additional
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- 2014
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162. Reducing Web Test Cases Aging by Means of Robust XPath Locators
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Leotta, Maurizio, primary, Stocco, Andrea, additional, Ricca, Filippo, additional, and Tonella, Paolo, additional
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- 2014
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163. PESTO: A Tool for Migrating DOM-Based to Visual Web Tests
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Stocco, Andrea, primary, Leotta, Maurizio, additional, Ricca, Filippo, additional, and Tonella, Paolo, additional
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- 2014
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164. Coordinate-Based Meta-Analysis of fMRI Studies with R
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Stocco, Andrea, primary
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- 2014
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165. Scaling Up High-Fidelity Cognitive Modeling to Real-World Applications
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CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF PSYCHOLOGY, Lebiere, Christian J, Stocco, Andrea, Reitter, David, Juvina, Ion, CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF PSYCHOLOGY, Lebiere, Christian J, Stocco, Andrea, Reitter, David, and Juvina, Ion
- Abstract
The approach presented in this paper addresses the question of the proper scientific basis for Human Factors modeling and proposes an architectural framework for integrating federated models and simulations. It is intended to be applicable to a broad range of scenarios across domains. Indeed, broad applicability and integration of modeling and simulation techniques are essential to their effectiveness and validation. Our approach is grounded in the concept of unified theories of cognition, implemented computationally as cognitive architectures. However, cognitive architectures also need to be constrained by our knowledge of neural processes in order to properly account for all cognitive, perceptual and motor factors. Despite that attention to the small-scale basis of cognition, cognitive modeling can scale up to social situations and large-scale network settings through a process of abstraction and integration. Key to that process is the availability of easily accessible resources in the form of existing cognitive models, implemented tasks, simulation environments adhering to a common standard, and human performance data to constrain and validate models. Investment in that infrastructure is essential to ensure growth and scalability in the application of cognitive models and their proper integration in military simulations., See also ADA564696. Human Modelling for Military Application (Applications militaires de la modelisation humaine). Supported in part by ONR Grant no. N00014-07-C-0912
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- 2010
166. Integrated Cognitive Architectures For Robust Decision Making
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CARNEGIE-MELLON UNIV PITTSBURGH PA, Anderson, John, Lebiere, Christian, O'Reilly, Randall, Stocco, Andrea, CARNEGIE-MELLON UNIV PITTSBURGH PA, Anderson, John, Lebiere, Christian, O'Reilly, Randall, and Stocco, Andrea
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Introduction The project s goal was to reproduce robust and intelligent decision making capabilities in artificial agents by integrating two successful cognitive architectures, ACT-R (Anderson, 2007) and Leabra (O Reiily & Munakata, 2000). The rationale was that such an integration effort would yield insights on the general mechanisms that allow rapid decision-making in real-time. Taken separately, ACTR and Leabra incorporate different views of how decision-making and robust behavior occur. The two architectures have different and complementary strengths and weaknesses and work at different levels of abstractions. Thus, an integration of the two would possibly yield a uniform framework for understanding the computational basis of robust intelligence and decision-making in humans., The original document contains color images.
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- 2010
167. Inhibitory synapses between striatal projection neurons support efficient enhancement of cortical signals: A computational model
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Stocco, Andrea, primary and Lebiere, Christian, additional
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- 2013
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168. The co-emergence of language and rules: Indirection, not recursion, is the key
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Stocco, Andrea, primary
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- 2013
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169. Web testware evolution
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Ricca, Filippo, primary, Leotta, Maurizio, additional, Stocco, Andrea, additional, Clerissi, Diego, additional, and Tonella, Paolo, additional
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- 2013
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170. Rapid instructed task learning: A new window into the human brain’s unique capacity for flexible cognitive control
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Cole, Michael W., primary, Laurent, Patryk, additional, and Stocco, Andrea, additional
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- 2012
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171. Bilingual brain training: A neurobiological framework of how bilingual experience improves executive function
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Stocco, Andrea, primary, Yamasaki, Brianna, additional, Natalenko, Rodion, additional, and Prat, Chantel S., additional
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- 2012
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172. Information routing in the basal ganglia: Highways to abnormal connectivity in autism?
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Prat, Chantel S., primary and Stocco, Andrea, additional
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- 2012
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173. Acetylcholine-Based Entropy in Response Selection: A Model of How Striatal Interneurons Modulate Exploration, Exploitation, and Response Variability in Decision-Making
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Stocco, Andrea, primary
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- 2012
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174. THE B-I-C-A OF BIOLOGICALLY INSPIRED COGNITIVE ARCHITECTURES
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STOCCO, ANDREA, primary, LEBIERE, CHRISTIAN, additional, and SAMSONOVICH, ALEXEI V., additional
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- 2010
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175. The Neural Correlates of Problem States: Testing fMRI Predictions of a Computational Model of Multitasking
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Borst, Jelmer P., primary, Taatgen, Niels A., additional, Stocco, Andrea, additional, and van Rijn, Hedderik, additional
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- 2010
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176. Dissociable processes underlying decisions in the Iowa Gambling Task: a new integrative framework
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Stocco, Andrea, primary, Fum, Danilo, additional, and Napoli, Antonio, additional
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- 2009
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177. Feasibility of adaptive intentional islanding operation of electric utility systems with distributed generation
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Caldon, Roberto, primary, Stocco, Andrea, additional, and Turri, Roberto, additional
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- 2008
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178. The cognitive modeling of human behavior: Why a model is (sometimes) better than 10,000 words
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Fum, Danilo, primary, Missier, Fabio Del, additional, and Stocco, Andrea, additional
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- 2007
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179. Adaptive islanded configuration for quality improvement in power delivery systems with distributed generation
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Caldon, Roberto, primary, Stocco, Andrea, additional, and Turri, Roberto, additional
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- 2005
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180. Bilingual brain training: A neurobiological framework of how bilingual experience improves executive function.
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Stocco, Andrea, Yamasaki, Brianna, Natalenko, Rodion, and Prat, Chantel S.
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BILINGUALISM , *NEUROBIOLOGY , *PREFRONTAL cortex , *INFORMATION processing , *BASAL ganglia - Abstract
Individuals who develop bilingually typically outperform monolinguals on tests of executive functions. This advantage likely reflects enhanced prefrontal function, but the mechanisms that underlie this improvement are still poorly understood. This article describes a theory on the nature of the neural underpinnings of improved executive function in bilinguals. Specifically, we propose that growing up in a bilingual environment trains a gating system in the striatum that flexibly routes information to the prefrontal cortex. This article is divided into three sections. Firstly, literature establishing a three-way connection between bilingualism, executive function, and fronto-striatal loops is summarized. Secondly, a computational model of information processing in the basal ganglia is described, illustrating how the striatal nuclei function to transfer information between cortical regions under prerequisite conditions. Finally, this model is extended to describe how bilingualism may “train the brain,” enabling improved performance under conditions of competitive information selection during information transfer. Theoretical implications and predictions of this theory are discussed. [ABSTRACT FROM AUTHOR]
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- 2014
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181. Let's talk, brain to brain.
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Stocco, Andrea and Hamzelou, Jessica
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COLLEGE teachers , *TELEPATHY , *KNOWLEDGE transfer , *COGNITION - Abstract
An interview with Cognition and Cortical Dynamics Laboratory Co-Director and assistant professor Andrea Stocco is presented which is conducted through a telepathy technology. Topics mentioned include the brain-to-brain communication, the essential devices used in transmitting information between brains and the benefits of telepathy communication.
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- 2016
182. Analysis of the human connectome data supports the notion of a "Common Model of Cognition" for human and human-like intelligence across domains.
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Stocco, Andrea, Sibert, Catherine, Steine-Hanson, Zoe, Koh, Natalie, Laird, John E., Lebiere, Christian J., and Rosenbloom, Paul
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ARTIFICIAL intelligence , *COGNITION , *FUNCTIONAL magnetic resonance imaging , *COGNITIVE science , *CAUSAL models - Abstract
The Common Model of Cognition (CMC) is a recently proposed, consensus architecture intended to capture decades of progress in cognitive science on modeling human and human-like intelligence. Because of the broad agreement around it and preliminary mappings of its components to specific brain areas, we hypothesized that the CMC could be a candidate model of the large-scale functional architecture of the human brain. To test this hypothesis, we analyzed functional MRI data from 200 participants and seven different tasks that cover a broad range of cognitive domains. The CMC components were identified with functionally homologous brain regions through canonical fMRI analysis, and their communication pathways were translated into predicted patterns of effective connectivity between regions. The resulting dynamic linear model was implemented and fitted using Dynamic Causal Modeling, and compared against six alternative brain architectures that had been previously proposed in the field of neuroscience (three hierarchical architectures and three hub-and-spoke architectures) using a Bayesian approach. The results show that, in all cases, the CMC vastly outperforms all other architectures, both within each domain and across all tasks. These findings suggest that a common set of architectural principles that could be used for artificial intelligence also underpins human brain function across multiple cognitive domains. [ABSTRACT FROM AUTHOR]
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- 2021
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183. Self-Reported Foot and Ankle Score: Italian Translation, Validation and Cross-Cultural Adaptation.
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Passafiume, Luca, Curti, Francesca, Marsocci1, Antonio, Cairoli, Alessio, Lombardo, Danilo, Lo Stocco, Andrea, Pogelli, Pierpaolo, and Magnifica, Fabrizio
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ANKLE physiology , *FOOT physiology , *PEARSON correlation (Statistics) , *CRONBACH'S alpha , *TRANSLATIONS , *RESEARCH methodology evaluation , *QUESTIONNAIRES , *RESEARCH methodology , *PSYCHOMETRICS , *INTRACLASS correlation , *SELF-perception - Abstract
Background. Nowadays the use of measurement instruments that evaluate the patient's condition is very common in the orthopedic field. We know that the most distal district of the lower limb, the osteoarticular complex of the ankle, is one of the most evaluated with rating scales; in fact, there are at least 76 different scoring systems for evaluating ankle problems. Furthermore, there is no measurement tool considered to be the absolute Gold Standard for evaluating problems affecting the ankle joint. Objectives. The main aim of this study was to translate, culturally adapt, and validate in Italian language the Self-Reported Foot and Ankle Score (SEFAS). Methods. The English version of the SEFAS has been translated according to international guidelines. The measurement properties (construct validity and reliability) have been tested according to COSMIN checklists. Cronbach's α was calculated to assess the internal consistency and the Intraclass Correlation Coefficient (ICC) was calculated to estimate the reliability. The Kaiser-Meier-Olkin (KMO), The Short-Form 36 (SF-36) and the EuroQol Health Questionnaire 5 Dimensions 5 Levels (EQ-5D-5L) were used to assess the construct validity and to verify sampling adequacy. A factorial analysis was used to confirm the mono-factorial nature of the scale. Results. All the items were similar in meaning to the originals. Cronbach's α was 0,880 and the ICC was 0.869. The Pearson's Correlation Coefficient showed significant correlations (p < 0.01) between SEFAS and SF-36 and EQ-5D-5L items. Conclusions. Based on the results obtained, we suggest the use of SEFAS in daily clinical practice, also promoting its continuation in the field of scientific research. [ABSTRACT FROM AUTHOR]
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- 2024
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184. Effects of bilingual language experience on basal ganglia computations: A dynamic causal modeling test of the conditional routing model.
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Yamasaki, Brianna L., Stocco, Andrea, Liu, Allison S., and Prat, Chantel S.
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BASAL ganglia , *CAUSAL models , *DYNAMIC models , *PREFRONTAL cortex , *NEUROPLASTICITY , *BIOLOGICAL models , *BRAIN mapping , *COMPARATIVE studies , *FRONTAL lobe , *MAGNETIC resonance imaging , *RESEARCH methodology , *MEDICAL cooperation , *MULTILINGUALISM , *RESEARCH , *EVALUATION research - Abstract
Bilingual language control is characterized by the ability to select from amongst competing representations based on the current language in use. According to the Conditional Routing Model (CRM), this feat is underpinned by basal-ganglia signal-routing mechanisms, and may have implications for cognitive flexibility. The current experiment used dynamic causal modeling of fMRI data to compare network-level brain functioning in monolinguals and bilinguals during a task that required productive (semantic decision) and receptive (language) switches. Consistent with the CRM, results showed that: (1) both switch types drove activation in the basal ganglia, (2) bilinguals and monolinguals differed in the strength of influence of dorsolateral prefrontal cortex (DLPFC) on basal ganglia, and (3) differences in bilingual language experience were marginally related to the strength of influence of the switching drives onto basal ganglia. Additionally, a task-by-group interaction was found, suggesting that when bilinguals engaged in language-switching, their task-switching costs were reduced. [ABSTRACT FROM AUTHOR]
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- 2019
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185. Testing machine learning based systems: a systematic mapping
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Riccio, Vincenzo, Jahangirova, Gunel, Stocco, Andrea, Humbatova, Nargiz, Weiss, Michael, Tonella, Paolo, Riccio, Vincenzo, Jahangirova, Gunel, Stocco, Andrea, Humbatova, Nargiz, Weiss, Michael, and Tonella, Paolo
- Abstract
Context: A Machine Learning based System (MLS) is a software system including one or more components that learn how to perform a task from a given data set. The increasing adoption of MLSs in safety critical domains such as autonomous driving, healthcare, and finance has fostered much attention towards the quality assurance of such systems. Despite the advances in software testing, MLSs bring novel and unprecedented challenges, since their behaviour is defined jointly by the code that implements them and the data used for training them. Objective: To identify the existing solutions for functional testing of MLSs, and classify them from three different perspectives: (1) the context of the problem they address, (2) their features, and (3) their empirical evaluation. To report demographic information about the ongoing research. To identify open challenges for future research. Method: We conducted a systematic mapping study about testing techniques for MLSs driven by 33 research questions. We followed existing guidelines when defining our research protocol so as to increase the repeatability and reliability of our results. Results: We identified 70 relevant primary studies, mostly published in the last years. We identified 11 problems addressed in the literature. We investigated multiple aspects of the testing approaches, such as the used/proposed adequacy criteria, the algorithms for test input generation, and the test oracles. Conclusions: The most active research areas in MLS testing address automated scenario/ input generation and test oracle creation. MLS testing is a rapidly growing and developing research area, with many open challenges, such as the generation of realistic inputs and the definition of reliable evaluation metrics and benchmarks.
186. A network-level analysis of cognitive flexibility reveals a differential influence of the anterior cingulate cortex in bilinguals versus monolinguals.
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Becker, Theresa M., Prat, Chantel S., and Stocco, Andrea
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COGNITIVE analysis , *CINGULATE cortex , *NEURAL circuitry , *BILINGUALISM , *COGNITIVE ability - Abstract
Mounting evidence suggests that bilingual development may change the brain in a way that gives rise to differences in non-linguistic cognitive functioning; however, only a limited number of studies have investigated the mechanism by which bilingualism shapes the brain. The current study used a network-level analysis to investigate differences in the mechanisms by which bilinguals and monolinguals flexibly adapt their neural networks in the face of novel task demands. Three competing hypotheses concerning differences in network-level adaptation were examined using Dynamic Causal Modeling of data from 15 bilinguals and 14 monolinguals who performed a Rapid Instructed Task Learning paradigm. The results demonstrated that the best-fitting model for the data from both groups specified that novel task execution is accomplished through a modulation of the influence of the anterior cingulate cortex (ACC) on the dorsolateral prefrontal cortex (DLPFC) and on the striatum. Further examination of the best-fitting model revealed that ACC activity increased DLPFC and striatal activity in bilinguals but decreased activity in these regions in monolinguals. Interestingly, an increased positive connection between the ACC and striatum was associated with decreased accuracy across groups. Taken together, the results suggest that regardless of language experience, the ACC plays a critical role in cognitive flexibility, but the exact influence of the ACC on other primary control regions seems to be dependent on language experience. When paired with the behavioral results, these results suggest that bilinguals and monolinguals may employ different neurocognitive mechanisms for conflict monitoring to flexibly adapt to novel situations. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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187. Supporting Safety Analysis of Deep Neural Networks with Automated Debugging and Repair
- Author
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Fahmy, Hazem, European Commission - EC [sponsor], Interdisciplinary Centre for Security, Reliability and Trust (SnT) > SVV - Software Verification and Validation [research center], Pastore, Fabrizio [superviser], Briand, Lionel [president of the jury], Stifter, Thomas [secretary], Stocco, Andrea [member of the jury], and Riccio, Vincenzo [member of the jury]
- Subjects
Computer science [C05] [Engineering, computing & technology] ,Sciences informatiques [C05] [Ingénierie, informatique & technologie] - Published
- 2023
188. Reflections of idiographic long-term memory characteristics in resting-state neuroimaging data.
- Author
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Zhou, Peiyun, Sense, Florian, van Rijn, Hedderik, and Stocco, Andrea
- Subjects
- *
LONG-term memory , *FALSE discovery rate , *SHORT-term memory , *COGNITIVE science , *BRAIN imaging , *BRAIN , *MEMORY , *RESEARCH , *RESEARCH methodology , *MEDICAL cooperation , *EVALUATION research , *COMPARATIVE studies , *NEURORADIOLOGY - Abstract
Translational applications of cognitive science depend on having predictive models at the individual, or idiographic, level. However, idiographic model parameters, such as working memory capacity, often need to be estimated from specific tasks, making them dependent on task-specific assumptions. Here, we explore the possibility that idiographic parameters reflect an individual's biology and can be identified from task-free neuroimaging measures. To test this hypothesis, we correlated a reliable behavioral trait, the individual rate of forgetting in long-term memory, with a readily available task-free neuroimaging measure, the resting-state EEG spectrum. Using an established, adaptive fact-learning procedure, the rate of forgetting for verbal and visual materials was measured in a sample of 50 undergraduates from whom we also collected eyes-closed resting-state EEG data. Statistical analyses revealed that the individual rates of forgetting were significantly correlated across verbal and visual materials. Importantly, both rates correlated with resting-state power levels in the low (13-15 Hz) and upper (15-17 Hz) portion of the beta frequency bands. These correlations were particularly strong for visuospatial materials, were distributed over multiple fronto-parietal locations, and remained significant even after a correction for multiple comparisons (False Discovery Rate) and after robust correlation methods were applied. These results suggest that computational models could be individually tailored for prediction using idiographic parameter values derived from inexpensive, task-free imaging recordings. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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189. A nonlinear dynamics phase oscillator model for the simulation of multistable perception
- Author
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Fürstenau, Norbert, Fum, Danilo, Del Misier, Fabio, and Stocco, Andrea
- Subjects
nonlinear dynamics ,limit cycle ,deterministic chaos ,cognitive modelling ,multistability ,synergetics ,perception ,simulation ,Systemergonomie ,phase oscillator ,attention - Abstract
A nonlinear dynamics model of multistable perception and numerical simulations of the quasiperiodic perception reversals due to ambiguous stimuli are presented. The perception state is formalized as the phase variable (order parameter) of a recursive cosinuidal map with the two control parameters μ= difference of meaning and G ~ attention. The mapping function is closely related to the neuronal mean field phase oscillator theory of temporal binding. Mean field interference with delayed phase feedback with gain ∼ G, delay T, and damping time τ enables transitions between chaotic and limit cycle attractors representing the perception states. Quasiperiodic perceptual reversals are induced by attention satiation (fatigue) G(t) with time constant γ. The coupled attention – perception dynamics reproduces the experimentally observed Γ-distribution of the reversal time statistics if a stochastic noise term is added to the attention equation. Mean reversal times of typically 3 – 5 s as reported in the literature, are correctly predicted if T is associated with the delay of 40 ms between stimulus onset and primary visual cortex (V1) response. Numerically determined perceptual transition times of 3 – 5 T are in reasonable agreement with stimulus – conscious perception delay of 150 – 200 ms (Lamme 2003). Eigenfrequencies of the limit cycle oscillations are in the range of 10 – 100 Hz, in agreement with typical EEG frequencies.
- Published
- 2005
190. One Size Does Not Fit All: Idiographic Computational Models Reveal Individual Differences in Learning and Meta-Learning Strategies.
- Author
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Haile TM, Prat CS, and Stocco A
- Abstract
Complex skill learning depends on the joint contribution of multiple interacting systems: working memory (WM), declarative long-term memory (LTM) and reinforcement learning (RL). The present study aims to understand individual differences in the relative contributions of these systems during learning. We built four idiographic, ACT-R models of performance on the stimulus-response learning, Reinforcement Learning Working Memory task. The task consisted of short 3-image, and long 6-image, feedback-based learning blocks. A no-feedback test phase was administered after learning, with an interfering task inserted between learning and test. Our four models included two single-mechanism RL and LTM models, and two integrated RL-LTM models: (a) RL-based meta-learning, which selects RL or LTM to learn based on recent success, and (b) a parameterized RL-LTM selection model at fixed proportions independent of learning success. Each model was the best fit for some proportion of our learners (LTM: 68.7%, RL: 4.8%, Meta-RL: 13.25%, bias-RL:13.25% of participants), suggesting fundamental differences in the way individuals deploy basic learning mechanisms, even for a simple stimulus-response task. Finally, long-term declarative memory seems to be the preferred learning strategy for this task regardless of block length (3- vs 6-image blocks), as determined by the large number of subjects whose learning characteristics were best captured by the LTM only model, and a preference for LTM over RL in both of our integrated-models, owing to the strength of our idiographic approach., (© 2024 Cognitive Science Society LLC.)
- Published
- 2024
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191. Reliance on Episodic vs. Procedural Systems in Decision-Making Depends on Individual Differences in Their Relative Neural Efficiency.
- Author
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Yang Y, Sibert CL, and Stocco A
- Abstract
Experiential decision-making can be explained as a result of either memory-based or reinforcement-based processes. Here, for the first time, we show that individual preferences between a memory-based and a reinforcement-based strategy, even when the two are functionally equivalent in terms of expected payoff, are adaptively shaped by individual differences in resting-state brain connectivity between the corresponding brain regions. Using computational cognitive models to identify which mechanism was most likely used by each participant, we found that individuals with comparatively stronger connectivity between memory regions prefer a memory-based strategy, while individuals with comparatively stronger connectivity between sensorimotor and habit-formation regions preferentially rely on a reinforcement-based strategy. These results suggest that human decision-making is adaptive and sensitive to the neural costs associated with different strategies., Competing Interests: Competing Interests The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a conflict of interest.
- Published
- 2024
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192. Allocating Mental Effort in Cognitive Tasks: A Model of Motivation in the ACT-R Cognitive Architecture.
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Yang YC and Stocco A
- Subjects
- Humans, Reward, Decision Making, Motivation, Cognition
- Abstract
Motivation is the driving force that influences people's behaviors and interacts with many cognitive functions. Computationally, motivation is represented as a cost-benefit analysis that weighs efforts and rewards in order to choose the optimal actions. Shenhav and colleagues proposed an elegant theory, the Expected Value of Control (EVC), which describes the relationship between cognitive efforts, costs, and rewards. In this paper, we propose a more fine-grained and detailed motivation framework that incorporates the principles of EVC into the ACT-R cognitive architecture. Specifically, motivation is represented as a specific slot in the Goal buffer with a corresponding scalar value, M, that is translated into the reward value R
t that is delivered when the goal is reached. This implementation is tested in two models. The first model is a high-level model that reproduces the EVC predictions with abstract actions. The second model is an augmented version of an existing ACT-R model of the Simon task. The motivation mechanism is shown to permit optimal effort allocation and reproduce known phenomena. Finally, the broader implications of our mechanism are discussed., (© 2023 Cognitive Science Society LLC.)- Published
- 2024
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193. Confidence-driven weighted retraining for predicting safety-critical failures in autonomous driving systems.
- Author
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Stocco A and Tonella P
- Abstract
Safe handling of hazardous driving situations is a task of high practical relevance for building reliable and trustworthy cyber-physical systems such as autonomous driving systems. This task necessitates an accurate prediction system of the vehicle's confidence to prevent potentially harmful system failures on the occurrence of unpredictable conditions that make it less safe to drive. In this paper, we discuss the challenges of adapting a misbehavior predictor with knowledge mined during the execution of the main system. Then, we present a framework for the continual learning of misbehavior predictors, which records in-field behavioral data to determine what data are appropriate for adaptation. Our framework guides adaptive retraining using a novel combination of in-field confidence metric selection and reconstruction error-based weighing. We evaluate our framework to improve a misbehavior predictor from the literature on the Udacity simulator for self-driving cars. Our results show that our framework can reduce the false positive rate by a large margin and can adapt to nominal behavior drifts while maintaining the original capability to predict failures up to several seconds in advance., (© 2021 The Authors. Journal of Software: Evolution and Process published by John Wiley & Sons Ltd.)
- Published
- 2022
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194. Individual Differences in Reward-Based Learning Predict Fluid Reasoning Abilities.
- Author
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Stocco A, Prat CS, and Graham LK
- Subjects
- Attention, Basal Ganglia, Humans, Problem Solving, Individuality, Reward
- Abstract
The ability to reason and problem-solve in novel situations, as measured by the Raven's Advanced Progressive Matrices (RAPM), is highly predictive of both cognitive task performance and real-world outcomes. Here we provide evidence that RAPM performance depends on the ability to reallocate attention in response to self-generated feedback about progress. We propose that such an ability is underpinned by the basal ganglia nuclei, which are critically tied to both reward processing and cognitive control. This hypothesis was implemented in a neurocomputational model of the RAPM task, which was used to derive novel predictions at the behavioral and neural levels. These predictions were then verified in one neuroimaging and two behavioral experiments. Furthermore, an effective connectivity analysis of the neuroimaging data confirmed a role for the basal ganglia in modulating attention. Taken together, these results suggest that individual differences in a neural circuit related to reward processing underpin human fluid reasoning abilities., (© 2021 Cognitive Science Society, Inc.)
- Published
- 2021
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195. Recovering Reliable Idiographic Biological Parameters from Noisy Behavioral Data: the Case of Basal Ganglia Indices in the Probabilistic Selection Task.
- Author
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Xu Y and Stocco A
- Abstract
Behavioral data, despite being a common index of cognitive activity, is under scrutiny for having poor reliability as a result of noise or lacking replications of reliable effects. Here, we argue that cognitive modeling can be used to enhance the test-retest reliability of the behavioral measures by recovering individual-level parameters from behavioral data. We tested this empirically with the Probabilistic Stimulus Selection (PSS) task, which is used to measure a participant's sensitivity to positive or negative reinforcement. An analysis of 400,000 simulations from an Adaptive Control of Thought-Rational (ACT-R) model of this task showed that the poor reliability of the task is due to the instability of the end-estimates: because of the way the task works, the same participants might sometimes end up having apparently opposite scores. To recover the underlying interpretable parameters and enhance reliability, we used a Bayesian Maximum A Posteriori (MAP) procedure. We were able to obtain reliable parameters across sessions (intraclass correlation coefficient ≈ 0.5). A follow-up study on a modified version of the task also found the same pattern of results, with very poor test-retest reliability in behavior but moderate reliability in recovered parameters (intraclass correlation coefficient ≈ 0.4). Collectively, these results imply that this approach can further be used to provide superior measures in terms of reliability, and bring greater insights into individual differences., (© Society for Mathematical Psychology 2021.)
- Published
- 2021
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196. BrainNet: A Multi-Person Brain-to-Brain Interface for Direct Collaboration Between Brains.
- Author
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Jiang L, Stocco A, Losey DM, Abernethy JA, Prat CS, and Rao RPN
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- Adolescent, Adult, Communication, Electroencephalography, Female, Healthy Volunteers, Humans, Male, Reproducibility of Results, Social Networking, Transcranial Magnetic Stimulation, Trust, Young Adult, Brain physiology, Brain-Computer Interfaces, Cooperative Behavior, Decision Making, Computer-Assisted, Decision Making, Shared
- Abstract
We present BrainNet which, to our knowledge, is the first multi-person non-invasive direct brain-to-brain interface for collaborative problem solving. The interface combines electroencephalography (EEG) to record brain signals and transcranial magnetic stimulation (TMS) to deliver information noninvasively to the brain. The interface allows three human subjects to collaborate and solve a task using direct brain-to-brain communication. Two of the three subjects are designated as "Senders" whose brain signals are decoded using real-time EEG data analysis. The decoding process extracts each Sender's decision about whether to rotate a block in a Tetris-like game before it is dropped to fill a line. The Senders' decisions are transmitted via the Internet to the brain of a third subject, the "Receiver," who cannot see the game screen. The Senders' decisions are delivered to the Receiver's brain via magnetic stimulation of the occipital cortex. The Receiver integrates the information received from the two Senders and uses an EEG interface to make a decision about either turning the block or keeping it in the same orientation. A second round of the game provides an additional chance for the Senders to evaluate the Receiver's decision and send feedback to the Receiver's brain, and for the Receiver to rectify a possible incorrect decision made in the first round. We evaluated the performance of BrainNet in terms of (1) Group-level performance during the game, (2) True/False positive rates of subjects' decisions, and (3) Mutual information between subjects. Five groups, each with three human subjects, successfully used BrainNet to perform the collaborative task, with an average accuracy of 81.25%. Furthermore, by varying the information reliability of the Senders by artificially injecting noise into one Sender's signal, we investigated how the Receiver learns to integrate noisy signals in order to make a correct decision. We found that like conventional social networks, BrainNet allows Receivers to learn to trust the Sender who is more reliable, in this case, based solely on the information transmitted directly to their brains. Our results point the way to future brain-to-brain interfaces that enable cooperative problem solving by humans using a "social network" of connected brains.
- Published
- 2019
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197. The bilingual language network: Differential involvement of anterior cingulate, basal ganglia and prefrontal cortex in preparation, monitoring, and execution.
- Author
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Seo R, Stocco A, and Prat CS
- Subjects
- Adolescent, Adult, Brain Mapping, Female, Humans, Magnetic Resonance Imaging, Male, Neural Pathways physiology, Young Adult, Basal Ganglia physiology, Executive Function physiology, Gyrus Cinguli physiology, Multilingualism, Prefrontal Cortex physiology
- Abstract
Research on the neural bases of bilingual language control has largely overlooked the role of preparatory processes, which are central to cognitive control. Additionally, little is known about how the processes involved in global language selection may differ from those involved in the selection of words and morpho-syntactic rules for manipulating them. These processes were examined separately in an fMRI experiment, with an emphasis on understanding how and when general cognitive control regions become activated. Results of region-of-interest analyses on 23 early Spanish-English bilinguals showed that the anterior cingulate cortex (ACC) was primarily engaged during the language preparation phase of the task, whereas the left prefrontal (DLPFC) and pre-supplementary motor areas showed increasing activation from preparation to execution. Activation in the basal ganglia (BG), left middle temporal lobe, and right precentral cortical regions did not significantly differ throughout the task. These results suggest that three core cognitive control regions, the ACC, DLPFC, and BG, which have been previously implicated in bilingual language control, engage in distinct neurocognitive processes. Specifically, the results are consistent with the view that the BG "keep track" of the target language in use throughout various levels of language selection, that the ACC is particularly important for top-down target language preparation, and that the left prefrontal cortex is increasingly involved in selection processes from preparation through task execution., (Published by Elsevier Inc.)
- Published
- 2018
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198. A Biologically Plausible Action Selection System for Cognitive Architectures: Implications of Basal Ganglia Anatomy for Learning and Decision-Making Models.
- Author
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Stocco A
- Subjects
- Humans, Basal Ganglia physiology, Cognition physiology, Decision Making physiology, Learning physiology, Models, Neurological, Neural Pathways physiology
- Abstract
Several attempts have been made previously to provide a biological grounding for cognitive architectures by relating their components to the computations of specific brain circuits. Often, the architecture's action selection system is identified with the basal ganglia. However, this identification overlooks one of the most important features of the basal ganglia-the existence of a direct and an indirect pathway that compete against each other. This characteristic has important consequences in decision-making tasks, which are brought to light by Parkinson's disease as well as genetic differences in dopamine receptors. This paper shows that a standard model of action selection in a cognitive architecture (ACT-R) cannot replicate any of these findings, details an alternative solution that reconciles action selection in the architecture with the physiology of the basal ganglia, and extends the domain of application of cognitive architectures. The implication of this solution for other architectures and existing models are discussed., (Copyright © 2017 Cognitive Science Society, Inc.)
- Published
- 2018
- Full Text
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199. Individual differences in the Simon effect are underpinned by differences in the competitive dynamics in the basal ganglia: An experimental verification and a computational model.
- Author
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Stocco A, Murray NL, Yamasaki BL, Renno TJ, Nguyen J, and Prat CS
- Subjects
- Adolescent, Adult, Decision Making physiology, Female, Humans, Male, Models, Theoretical, Neuropsychological Tests, Reaction Time physiology, Young Adult, Attention physiology, Basal Ganglia physiology, Executive Function physiology, Individuality, Memory, Short-Term physiology
- Abstract
Cognitive control is thought to be made possible by the activity of the prefrontal cortex, which selectively uses task-specific representations to bias the selection of task-appropriate responses over more automated, but inappropriate, ones. Recent models have suggested, however, that prefrontal representations are in turn controlled by the basal ganglia. In particular, neurophysiological considerations suggest that the basal ganglia's indirect pathway plays a pivotal role in preventing irrelevant information from being incorporated into a task, thus reducing response interference due to the processing of inappropriate stimuli dimensions. Here, we test this hypothesis by showing that individual differences in a non-verbal cognitive control task (the Simon task) are correlated with performance on a decision-making task (the Probabilistic Stimulus Selection task) that tracks the contribution of the indirect pathway. Specifically, the higher the effect of the indirect pathway, the smaller was the behavioral costs associated with suppressing interference in incongruent trials. Additionally, it was found that this correlation was driven by individual differences in incongruent trials only (with little effect on congruent ones) and specific to the indirect pathway (with almost no correlation with the effect of the direct pathways). Finally, it is shown that this pattern of results is precisely what is predicted when competitive dynamics of the basal ganglia are added to the selective attention component of a simple model of the Simon task, thus showing that our experimental results can be fully explained by our initial hypothesis., (Published by Elsevier B.V.)
- Published
- 2017
- Full Text
- View/download PDF
200. Basal ganglia impairments in autism spectrum disorder are related to abnormal signal gating to prefrontal cortex.
- Author
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Prat CS, Stocco A, Neuhaus E, and Kleinhans NM
- Subjects
- Adult, Autism Spectrum Disorder diagnostic imaging, Basal Ganglia Diseases diagnostic imaging, Brain Mapping, Case-Control Studies, Executive Function physiology, Female, Humans, Image Processing, Computer-Assisted, Male, Middle Aged, Models, Neurological, Neuropsychological Tests, Oxygen blood, Photic Stimulation, Prefrontal Cortex diagnostic imaging, Psychiatric Status Rating Scales, Young Adult, Autism Spectrum Disorder complications, Autism Spectrum Disorder pathology, Basal Ganglia Diseases complications, Cortical Synchronization physiology, Prefrontal Cortex physiopathology
- Abstract
Research on the biological basis of autism spectrum disorder has yielded a list of brain abnormalities that are arguably as diverse as the set of behavioral symptoms that characterize the disorder. Among these are patterns of abnormal cortical connectivity and abnormal basal ganglia development. In attempts to integrate the existing literature, the current paper tests the hypothesis that impairments in the basal ganglia's function to flexibly select and route task-relevant neural signals to the prefrontal cortex underpins patterns of abnormal synchronization between the prefrontal cortex and other cortical processing centers observed in individuals with autism spectrum disorder (ASD). We tested this hypothesis using a Dynamic Causal Modeling analysis of neuroimaging data collected from 16 individuals with ASD (mean age=25.3 years; 6 female) and 17 age- and IQ-matched neurotypical controls (mean age=25.6, 6 female), who performed a Go/No-Go test of executive functioning. Consistent with the hypothesis tested, a random-effects Bayesian model selection procedure determined that a model of network connectivity in which basal ganglia activation modulated connectivity between the prefrontal cortex and other key cortical processing centers best fit the data of both neurotypicals and individuals with ASD. Follow-up analyses suggested that the largest group differences were observed for modulation of connectivity between prefrontal cortex and the sensory input region in the occipital lobe [t(31)=2.03, p=0.025]. Specifically, basal ganglia activation was associated with a small decrease in synchronization between the occipital region and prefrontal cortical regions in controls; however, in individuals with ASD, basal ganglia activation resulted in increased synchronization between the occipital region and the prefrontal cortex. We propose that this increased synchronization may reflect a failure in basal ganglia signal gating mechanisms, resulting in a non-selective copying of signals to prefrontal cortex. Such a failure to prioritize and filter signals to the prefrontal cortex could result in the pervasive impairments in cognitive flexibility and executive functioning that characterize autism spectrum disorder, and may offer a mechanistic explanation of some of the observed abnormalities in patterns of cortical synchronization in ASD., (Published by Elsevier Ltd.)
- Published
- 2016
- Full Text
- View/download PDF
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