DSpace Angular :: Browsing by Author "Ibanez, Agustin"

Browsing by Author "Ibanez, Agustin"

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Allostatic-interoceptive anticipation of social rejection
(2023) Migeot, Joaquin; Hesse, Eugenia; Fittipaldi, Sol; Mejia, Jhonny; Fraile, Matias; Garcia, Adolfo M.; Garcia, Maria del Carmen; Ortega, Rodrigo; Lawlor, Brian; Lopez, Vladimir; Ibanez, Agustin
Anticipating social stress evokes strong reactions in the organism, including interoceptive modulations. However, evidence for this claim comes from behavioral studies, often with inconsistent results, and relates almost solely to the reactive and recovery phase of social stress exposure. Here, we adopted an allostatic-interoceptive predictive coding framework to study interoceptive and exteroceptive anticipatory brain responses using a social rejection task. We analyzed the heart -evoked potential (HEP) and task-related oscillatory activity of 58 adolescents via scalp EEG, and 385 human intracranial recordings of three patients with intractable epilepsy. We found that anticipatory interoceptive signals increased in the face of unexpected social outcomes, reflected in larger negative HEP modulations. Such signals emerged from key brain allostatic-interoceptive network hubs, as shown by intracranial recordings. Exteroceptive signals were characterized by early activity between 1-15 Hz across conditions, and modulated by the probabilistic anticipation of reward-related outcomes, observed over distributed brain regions. Our findings suggest that the anticipation of a social outcome is characterized by allostatic-interoceptive modulations that prepare the organism for possible rejection. These results inform our understanding of interoceptive processing and constrain neurobiological models of social stress.
Allostatic-Interoceptive Overload in Frontotemporal Dementia
(2022) Birba, Agustina; Santamaria-Garcia, Hernando; Prado, Pavel; Cruzat, Josefina; Sainz Ballesteros, Agustin; Legaz, Agustina; Fittipaldi, Sol; Duran-Aniotz, Claudia; Slachevsky, Andrea; Santibanez, Rodrigo; Sigman, Mariano; Garcia, Adolfo M.; Whelan, Robert; Moguilner, Sebastian; Ibanez, Agustin
BACKGROUND: The predictive coding theory of allostatic-interoceptive load states that brain networks mediating autonomic regulation and interoceptive-exteroceptive balance regulate the internal milieu to anticipate future needs and environmental demands. These functions seem to be distinctly compromised in behavioral variant frontotemporal dementia (bvFTD), including alterations of the allostatic-interoceptive network (AIN). Here, we hypothesize that bvFTD is typified by an allostatic-interoceptive overload.
Apathy, Executive Function, and Emotion Recognition Are the Main Drivers of Functional Impairment in Behavioral Variant of Frontotemporal Dementia
(FRONTIERS MEDIA SA, 2022) Musa Salech, Gada; Lillo, Patricia; van der Hiele, Karin; Mendez Orellana, Carolina; Ibanez, Agustin; Slachevsky, Andrea
Background: The cognitive and neuropsychiatric deficits present in patients with behavioral variant frontotemporal dementia (bvFTD) are associated with loss of functionality in the activities of daily living (ADLs). The main purpose of this study was to examine and explore the association between the cognitive and neuropsychiatric features that might prompt functional impairment of basic, instrumental, and advanced ADL domains in patients with bvFTD.Methods: A retrospective cross-sectional study was conducted with 27 patients with bvFTD in its early stage (<2 years of evolution) and 32 healthy control subjects. A neuropsychological assessment was carried out wherein measures of cognitive function and neuropsychiatric symptoms were obtained. The informant-report Technology-Activities of Daily Living Questionnaire was used to assess the percentage of functional impairment in the different ADL domains. To identify the best determinants, three separate multiple regression analyses were performed, considering each functional impairment as the dependent variable and executive function, emotion recognition, disinhibition, and apathy as independent variables.Results: For the basic ADLs, a model that explains 28.2% of the variability was found, in which the presence of apathy (beta = 0.33, p = 0.02) and disinhibition (beta = 0.29, p = 0.04) were significant factors. Concerning instrumental ADLs, the model produced accounted for 63.7% of the functional variability, with the presence of apathy (beta = 0.71, p < 0.001), deficits in executive function (beta = -0.36, p = 0.002), and lack of emotion recognition (beta = 0.28, p = 0.017) as the main contributors. Finally, in terms of advanced ADLs, the model found explained 52.6% of the variance, wherein only the presence of apathy acted as a significant factor (beta = 0.59, p < 0.001).Conclusions: The results of this study show the prominent and transverse effect of apathy in the loss of functionality throughout all the ADL domains. Apart from that, this is the first study that shows that the factors associated with loss of functionality differ according to the functional domain in patients with bvFTD in its early stage. Finally, no other study has analyzed the impact of the lack of emotion recognition in the functionality of ADLs. These results could guide the planning of tailored interventions that might enhance everyday activities and the improvement of quality of life.
Applauding with Closed Hands: Neural Signature of Action-Sentence Compatibility Effects
(PUBLIC LIBRARY SCIENCE, 2010) Aravena, Pia; Hurtado, Esteban; Riveros, Rodrigo; Cardona, Juan Felipe; Manes, Facundo; Ibanez, Agustin
Background: Behavioral studies have provided evidence for an action-sentence compatibility effect (ACE) that suggests a coupling of motor mechanisms and action-sentence comprehension. When both processes are concurrent, the action sentence primes the actual movement, and simultaneously, the action affects comprehension. The aim of the present study was to investigate brain markers of bidirectional impact of language comprehension and motor processes.
Biomarkers for dementia in Latin American countries: Gaps and opportunities
(2023) Parra, Mario A.; Orellana, Paulina; Leon, Tomas; Victoria, Cabello G.; Henriquez, Fernando; Gomez, Rodrigo; Avalos, Constanza; Damian, Andres; Slachevsky, Andrea; Ibanez, Agustin; Zetterberg, Henrik; Tijms, Betty M.; Yokoyama, Jennifer S.; Pina-Escudero, Stefanie D.; Cochran, J. Nicholas; Matallana, Diana L.; Acosta, Daisy; Allegri, Ricardo; Arias-Suarez, Bianca P.; Barra, Bernardo; Behrens, Maria Isabel; Brucki, SoniaM. D.; Busatto, Geraldo; Caramelli, Paulo; Castro-Suarez, Sheila; Contreras, Valeria; Custodio, Nilton; Dansilio, Sergio; De la Cruz-Puebla, Myriam; de Souza, Leonardo Cruz; Diaz, Monica M.; Duque, Lissette; Farias, Gonzalo A.; Ferreira, Sergio T.; Guimet, Nahuel Magrath; Kmaid, Ana; Lira, David; Lopera, Francisco; Meza, Beatriz Mar; Miotto, Eliane C.; Nitrini, Ricardo; Nunez, Alberto; O'Neill, Santiago; Ochoa, John; Pintado-Caipa, Maritza; Resende, Elisa de Paula Franca; Risacher, Shannon; Rojas, Luz Angela; Sabaj, Valentina; Schilling, Lucas; Sellek, Allis F.; Sosa, Ana; Takada, Leonel T.; Teixeira, Antonio L.; Unaucho-Pilalumbo, Martha; Duran-Aniotz, Claudia
Limited knowledge on dementia biomarkers in Latin American and Caribbean (LAC) countries remains a serious barrier. Here, we reported a survey to explore the ongoing work, needs, interests, potential barriers, and opportunities for future studies related to biomarkers. The results show that neuroimaging is the most used biomarker (73%), followed by genetic studies (40%), peripheral fluids biomarkers (31%), and cerebrospinal fluid biomarkers (29%). Regarding barriers in LAC, lack of funding appears to undermine the implementation of biomarkers in clinical or research settings, followed by insufficient infrastructure and training. The survey revealed that despite the above barriers, the region holds a great potential to advance dementia biomarkers research. Considering the unique contributions that LAC could make to this growing field, we highlight the urgent need to expand biomarker research. These insights allowed us to propose an action plan that addresses the recommendations for a biomarker framework recently proposed by regional experts.
Chronic neuropsychiatric sequelae of SARS-CoV-2: Protocol and methods from the Alzheimer's Association Global Consortium
(2022) de Erausquin, Gabriel A.; Snyder, Heather; Brugha, Traolach S.; Seshadri, Sudha; Carrillo, Maria; Sagar, Rajesh; Huang, Yueqin; Newton, Charles; Tartaglia, Carmela; Teunissen, Charlotte; Hakanson, Krister; Akinyemi, Rufus; Prasad, Kameshwar; D'Avossa, Giovanni; Gonzalez-Aleman, Gabriela; Hosseini, Akram; Vavougios, George D.; Sachdev, Perminder; Bankart, John; Mors, Niels Peter Ole; Lipton, Richard; Katz, Mindy; Fox, Peter T.; Katshu, Mohammad Zia; Iyengar, M. Sriram; Weinstein, Galit; Sohrabi, Hamid R.; Jenkins, Rachel; Stein, Dan J.; Hugon, Jacques; Mavreas, Venetsanos; Blangero, John; Cruchaga, Carlos; Krishna, Murali; Wadoo, Ovais; Becerra, Rodrigo; Zwir, Igor; Longstreth, William T.; Kroenenberg, Golo; Edison, Paul; Mukaetova-Ladinska, Elizabeta; Staufenberg, Ekkehart; Figueredo-Aguiar, Mariana; Yecora, Agustin; Vaca, Fabiana; Zamponi, Hernan P.; Lo Re, Vincenzina; Majid, Abdul; Sundarakumar, Jonas; Gonzalez, Hector M.; Geerlings, Mirjam, I; Skoog, Ingmar; Salmoiraghi, Alberto; Boneschi, Filippo Martinelli; Patel, Vibuthi N.; Santos, Juan M.; Rivera Arroyo, Guillermo; Caballero Moreno, Antonio; Felix, Pascal; Gallo, Carla; Arai, Hidenori; Yamada, Masahito; Iwatsubo, Takeshi; Sharma, Malveeka; Chakraborty, Nandini; Ferreccio, Catterina; Akena, Dickens; Brayne, Carol; Maestre, Gladys; Blangero, Sarah Williams; Brusco, Luis, I; Siddarth, Prabha; Hughes, Timothy M.; Zuniga, Alfredo Ramirez; Kambeitz, Joseph; Laza, Agustin Ruiz; Allen, Norrina; Panos, Stella; Merrill, David; Ibanez, Agustin; Tsuang, Debby; Valishvili, Nino; Shrestha, Srishti; Wang, Sophia; Padma, Vasantha; Anstey, Kaarin J.; Ravindrdanath, Vijayalakshmi; Blennow, Kaj; Mullins, Paul; Pria, Anand; Mosley, Thomas H.; Gowland, Penny; Girard, Timothy D.; Bowtell, Richard; Vahidy, Farhaan S.
Introduction Coronavirus disease 2019 (COVID-19) has caused >3.5 million deaths worldwide and affected >160 million people. At least twice as many have been infected but remained asymptomatic or minimally symptomatic. COVID-19 includes central nervous system manifestations mediated by inflammation and cerebrovascular, anoxic, and/or viral neurotoxicity mechanisms. More than one third of patients with COVID-19 develop neurologic problems during the acute phase of the illness, including loss of sense of smell or taste, seizures, and stroke. Damage or functional changes to the brain may result in chronic sequelae. The risk of incident cognitive and neuropsychiatric complications appears independent from the severity of the original pulmonary illness. It behooves the scientific and medical community to attempt to understand the molecular and/or systemic factors linking COVID-19 to neurologic illness, both short and long term. Methods This article describes what is known so far in terms of links among COVID-19, the brain, neurological symptoms, and Alzheimer's disease (AD) and related dementias. We focus on risk factors and possible molecular, inflammatory, and viral mechanisms underlying neurological injury. We also provide a comprehensive description of the Alzheimer's Association Consortium on Chronic Neuropsychiatric Sequelae of SARS-CoV-2 infection (CNS SC2) harmonized methodology to address these questions using a worldwide network of researchers and institutions. Results Successful harmonization of designs and methods was achieved through a consensus process initially fragmented by specific interest groups (epidemiology, clinical assessments, cognitive evaluation, biomarkers, and neuroimaging). Conclusions from subcommittees were presented to the whole group and discussed extensively. Presently data collection is ongoing at 19 sites in 12 countries representing Asia, Africa, the Americas, and Europe. Discussion The Alzheimer's Association Global Consortium harmonized methodology is proposed as a model to study long-term neurocognitive sequelae of SARS-CoV-2 infection. Key Points The following review describes what is known so far in terms of molecular and epidemiological links among COVID-19, the brain, neurological symptoms, and AD and related dementias (ADRD) The primary objective of this large-scale collaboration is to clarify the pathogenesis of ADRD and to advance our understanding of the impact of a neurotropic virus on the long-term risk of cognitive decline and other CNS sequelae. No available evidence supports the notion that cognitive impairment after SARS-CoV-2 infection is a form of dementia (ADRD or otherwise). The longitudinal methodologies espoused by the consortium are intended to provide data to answer this question as clearly as possible controlling for possible confounders. Our specific hypothesis is that SARS-CoV-2 triggers ADRD-like pathology following the extended olfactory cortical network (EOCN) in older individuals with specific genetic susceptibility. The proposed harmonization strategies and flexible study designs offer the possibility to include large samples of under-represented racial and ethnic groups, creating a rich set of harmonized cohorts for future studies of the pathophysiology, determinants, long-term consequences, and trends in cognitive aging, ADRD, and vascular disease. We provide a framework for current and future studies to be carried out within the Consortium.
Cortical deficits of emotional face processing in adults with ADHD: Its relation to social cognition and executive function
(ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2011) Ibanez, Agustin; Petroni, Agustin; Urquina, Hugo; Torrente, Fernando; Torralva, Teresa; Hurtado, Esteban; Guex, Raphael; Blenkmann, Alejandro; Beltrachini, Leandro; Muravchik, Carlos; Baez, Sandra; Cetkovich, Marcelo; Sigman, Mariano; Lischinsky, Alicia; Manes, Facundo
Although it has been shown that adults with attention-deficit hyperactivity disorder (ADHD) have impaired social cognition, no previous study has reported the brain correlates of face valence processing. This study looked for behavioral, neuropsychological, and electrophysiological markers of emotion processing for faces (N170) in adult ADHD compared to controls matched by age, gender, educational level, and handedness. We designed an event-related potential (ERP) study based on a dual valence task (DVT), in which faces and words were presented to test the effects of stimulus type (faces, words, or face-word stimuli) and valence (positive versus negative). Individual signatures of cognitive functioning in participants with ADHD and controls were assessed with a comprehensive neuropsychological evaluation, including executive functioning (EF) and theory of mind (ToM). Compared to controls, the adult ADHD group showed deficits in N170 emotion modulation for facial stimuli. These N170 impairments were observed in the absence of any deficit in facial structural processing, suggesting a specific ADHD impairment in early facial emotion modulation. The cortical current density mapping of N170 yielded a main neural source of N170 at posterior section of fusiform gyrus (maximum at left hemisphere for words and right hemisphere for faces and simultaneous stimuli). Neural generators of N170 (fusiform gyrus) were reduced in ADHD. In those patients, N170 emotion processing was associated with performance on an emotional inference ToM task, and N170 from simultaneous stimuli was associated with EF, especially working memory. This is the first report to reveal an adult ADHD-specific impairment in the cortical modulation of emotion for faces and an association between N170 cortical measures and ToM and EF.
Electrophysiological evidence of different interpretative strategies in irony comprehension
(2007) Cornejo, Carlos; Simonetti, Franco; Aldunate, Nerea; Ibanez, Agustin; Lopez, Vladimir; Melloni, Lucia
We explore the hypothesis that induction of holistic or analytic strategies influences comprehension and processing of highly contextualized expressions of ordinary language, such as irony. Twenty undergraduate students were asked to categorize as coherent or incoherent a group of sentences. Each sentence completed a previous story, so that they could be ironical, literal or nonsensical endings. Participants were asked to evaluate whether each sentence was coherent or incoherent. Half of them were initially instructed to consider whether the sentences made sense (holistic condition); the other half were instructed to consider whether the sentences were congruent or incongruent (analytic condition). Behavioral responses and Event Related Potentials were registered during the experiment. Both behavioral and electrophysiological results allow clearly distinguishing between the holistic and the analytic strategies. The fact that the same set of stimuli elicits different ERP waveforms, depending on the strategy with which they are analyzed, suggests that different cognitive processes and different areas of the brain are operating in each case.
ERPs and contextual semantic discrimination: Degrees of congruence in wakefulness and sleep
(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2006) Ibanez, Agustin; Lopez, Vladimir; Cornejo, Carlos
This study explores whether the brain can discriminate degrees of semantic congruency during wakefulness and sleep. Experiment 1 was conducted during wakefulness to test degrees of congruency by means of N400 amplitude. In Experiment 2, the same paradigm was applied to a different group of participants during natural night sleep. Stimuli were 108 sentences (definitions with two attributes) with four possible degrees of congruence as ending targets. In both studies, the amplitude of N400-like effect showed modulation according to the degree of congruency. The results indicate that the brain can accomplish sentential semantic discriminations not only in wakefulness but also in sleep. (c) 2006 Elsevier Inc. All rights reserved.
Exploring the relationship between vagal tone and event-related potentials in response to an affective picture task
(ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2011) Dufey, Michele; Hurtado, Esteban; Maria Fernandez, Ana; Manes, Facundo; Ibanez, Agustin
The present study is the first to investigate the relationship between vagal tone level and event-related potentials (ERPs) in adults. Numerous studies have shown a relationship between vagal tone and the individual differences between a variety of psychophysiological, affective, and social outcomes. This suggests that vagal tone can be related to how people process relevant affective social information at the brain level. This study aimed to assess whether the ERP response varies between high and low vagal tone groups, in the face of salient affective information. In the experimental cohort, two groups were separated according to their vagal tone level. ERPs were recorded while individuals performed an affective picture task that included positive, neutral, and negative emotional stimuli. Differences between the high and low vagal tone groups were observed at the early posterior negativity for both positive and negative valences, and at the late positive potential for all the categories. It can be concluded that differences between high and low vagal tone levels are related to differences in the ERPs at early, middle, and late latencies. The results are discussed with respect to the effect of differences between the vagal tone conditions on various stages of information-processing.
Fluid Intelligence and Psychosocial Outcome: From Logical Problem Solving to Social Adaptation
(PUBLIC LIBRARY SCIENCE, 2011) Huepe, David; Roca, Maria; Salas, Natalia; Canales Johnson, Andres; Rivera Rei, Alvaro A.; Zamorano, Leandro; Concepcion, Aimee; Manes, Facundo; Ibanez, Agustin
Background: While fluid intelligence has proved to be central to executive functioning, logical reasoning and other frontal functions, the role of this ability in psychosocial adaptation has not been well characterized.
Gesture and metaphor comprehension: Electrophysiological evidence of cross-modal coordination by audiovisual stimulation
(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2009) Cornejo, Carlos; Simonetti, Franco; Ibanez, Agustin; Aldunate, Nerea; Ceric, Francisco; Lopez, Vladimir; Nunez, Rafael E.
In recent years, studies have suggested that gestures influence comprehension of linguistic expressions, for example, eliciting an N400 component in response to a speech/gesture mismatch. In this paper, we investigate the role of gestural information in the understanding of metaphors. Event related potentials (ERPs) were recorded while participants viewed video clips of an actor uttering metaphorical expressions and producing bodily gestures that were congruent or incongruent with the metaphorical meaning of such expressions. This modality of stimuli presentation allows a more ecological approach to meaning integration. When ERPs were calculated using gesture stroke as time-lock event, gesture incongruity with metaphorical expression modulated the amplitude of the N400 and of the late positive complex (LPC). This suggests that gestural and speech information are combined online to make sense of the interlocutor's linguistic production in an early stage of metaphor comprehension. Our data favor the idea that meaning construction is globally integrative and highly context-sensitive. (C) 2008 Elsevier Inc. All rights reserved.
Gesture influences the processing of figurative language in non-native speakers: ERP evidence
(2010) Ibanez, Agustin; Manes, Facundo; Escobar, Josefina; Trujillo, Natalia; Andreucci, Paola; Hurtado, Esteban
Gestures should play a role in second language comprehension, given their importance in conveying contextual information. In this study, the N400 and the LPC were evaluated in a task involving the observation of videos showing utterances accompanied by gestures. Students studying advanced (G-High participants) and basic German (G-Low participants) as a second language were investigated. The utterance-gesture congruence and metaphoric meaning of content were manipulated during the task. As in previous ERP reports with native speakers, metaphorical expressions were sensitive to gestures. In G-Low participants, no modulation in the 300-500 ms window was observed, and only a modest effect was observed for the 500-700 ms window. More subtle differences of verbal expression were not processed in this group. Consistent with previous reports of the same paradigm with native speakers, the N400 from G-High group discriminated both congruent and incongruent gestures as well as literal and metaphorical sentences. Our results suggest that semantic processing is robust in the learning of a second language, although the amplitude modulation and latency of ERPs might depend on the speaker's proficiency level. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
High contextual sensitivity of metaphorical expressions and gesture blending: A video event-related potential design
(ELSEVIER IRELAND LTD, 2011) Ibanez, Agustin; Toro, Pablo; Cornejo, Carlos; Hurquina, Hugo; Manes, Facundo; Weisbrod, Matthias; Schroeder, Johannes
Human communication in a natural context implies the dynamic coordination of contextual clues, paralinguistic information and literal as well as figurative language use. In the present study we constructed a paradigm with four types of video clips: literal and metaphorical expressions accompanied by congruent and incongruent gesture actions. Participants were instructed to classify the gesture accompanying the expression as congruent or incongruent by pressing two different keys while electrophysiological activity was being recorded. We compared behavioral measures and event related potential (ERP) differences triggered by the gesture stroke onset. Accuracy data showed that incongruent metaphorical expressions were more difficult to classify. Reaction times were modulated by incongruent gestures, by metaphorical expressions and by a gesture-expression interaction. No behavioral differences were found between the literal and metaphorical expressions when the gesture was congruent. N400-like and LPC-like (late positive complex) components from metaphorical expressions produced greater negativity. The N400-like modulation of metaphorical expressions showed a greater difference between congruent and incongruent categories over the left anterior region, compared with the literal expressions. More importantly, the literal congruent as well as the metaphorical congruent categories did not show any difference. Accuracy, reaction times and ERPs provide convergent support for a greater contextual sensitivity of the metaphorical expressions. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
Human cognition in context
(2008) Cosmelli, Diego; Ibanez, Agustin
The aim of this special issue of IPBS has been to explore concrete and explicit alternatives to cognitivism. Indeed, in our editorial introduction we set out to give a brief survey of the numerous criticisms that have been made of understanding the mind this way (Ibanez and Cosmelli, Integrative Psychological and Behavioral Sciences, 2008). Thus in what sense do the contributions here presented succeed in providing novel alternatives, moving into original and potentially generative domains of inquiry? While much remains to be done, we believe that they make significant headway in more than one sense. We do believe, however, that there is one locus that furnishes a convergence ground that is worth considering seriously: the problem of meaning. Meaning as making sense of contextualized action seems to cross the domains of intentionality, intersubjectivity and ecology of mind. The development of multilevel approaches, as the authors here exemplify, argues for a novel research agenda.
In your phase: neural phase synchronisation underlies visual imagery of faces
(2021) Canales-Johnson, Andres; Lanfranco, Renzo C.; Morales, Juan Pablo; Martinez-Pernia, David; Valdes, Joaquin; Ezquerro-Nassar, Alejandro; Rivera-Rei, Alvaro; Ibanez, Agustin; Chennu, Srivas; Bekinschtein, Tristan A.; Huepe, David; Noreika, Valdas
Mental imagery is the process through which we retrieve and recombine information from our memory to elicit the subjective impression of "seeing with the mind's eye". In the social domain, we imagine other individuals while recalling our encounters with them or modelling alternative social interactions in future. Many studies using imaging and neurophysiological techniques have shown several similarities in brain activity between visual imagery and visual perception, and have identified frontoparietal, occipital and temporal neural components of visual imagery. However, the neural connectivity between these regions during visual imagery of socially relevant stimuli has not been studied. Here we used electroencephalography to investigate neural connectivity and its dynamics between frontal, parietal, occipital and temporal electrodes during visual imagery of faces. We found that voluntary visual imagery of faces is associated with long-range phase synchronisation in the gamma frequency range between frontoparietal electrode pairs and between occipitoparietal electrode pairs. In contrast, no effect of imagery was observed in the connectivity between occipitotemporal electrode pairs. Gamma range synchronisation between occipitoparietal electrode pairs predicted subjective ratings of the contour definition of imagined faces. Furthermore, we found that visual imagery of faces is associated with an increase of short-range frontal synchronisation in the theta frequency range, which temporally preceded the long-range increase in the gamma synchronisation. We speculate that the local frontal synchrony in the theta frequency range might be associated with an effortful top-down mnemonic reactivation of faces. In contrast, the long-range connectivity in the gamma frequency range along the fronto-parieto-occipital axis might be related to the endogenous binding and subjective clarity of facial visual features.
Neural Processing of Emotional Facial and Semantic Expressions in Euthymic Bipolar Disorder (BD) and Its Association with Theory of Mind (ToM)
(2012) Ibanez, Agustin; Urquina, Hugo; Petroni, Agustin; Baez, Sandra; Lopez, Vladimir; do Nascimento, Micaela; Herrera, Eduar; Guex, Raphael; Hurtado, Esteban; Blenkmann, Alejandro; Beltrachini, Leandro; Gelormini, Carlos; Sigman, Mariano; Lischinsky, Alicia; Torralva, Teresa; Torrente, Fernando; Cetkovich, Marcelo; Manes, Facundo
Background: Adults with bipolar disorder (BD) have cognitive impairments that affect face processing and social cognition. However, it remains unknown whether these deficits in euthymic BD have impaired brain markers of emotional processing.
Potential consequences of abandonment in preschool-age: Neuropsychological findings in institutionalized children
(HINDAWI LTD, 2012) Cardona, Juan F.; Manes, Facundo; Escobar, Josefina; Lopez, Jessica; Ibanez, Agustin
Objective: Several longitudinal studies had shown that early deprivation and institutionalization during the first six months of life affects the emotional, cognitive, social and neurophysiologic development. Nevertheless, our understanding of possible similar effects of delayed institutionalization, in preschool-age remains unclear to this day. The goal of this study is to evaluate the cognitive performance of institutionalized children with history of preschool-age physical abandonment.
Size and probability of rewards modulate the feedback error-related negativity associated with wins but not losses in a monetarily rewarded gambling task
(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2010) San Martin, Rene; Manes, Facundo; Hurtado, Esteban; Isla, Pablo; Ibanez, Agustin
Feedback error-related negativity (fERN) has been referred to as a negative deflection in the event related potential (ERP), which distinguishes between wins and losses in terms of expected and unexpected outcomes. Some studies refer to the "expected outcome" as the probability to win vs. to lose, and others as expected size of rewards. We still do not know much about whether these alternative interpretations of "expected outcome" affect the fERN in a different manner, nor do we know the effect of their interaction in an expected value fashion. We set a gambling task with four game categories; two had the same expected value, while the other two categories were equivalent to the first ones, but alternatively in the size or probability of the offered rewards. Results show that fERN preceded by a P200, and followed by a Pe-like wave differentiates between losing in the category with a higher expected value and the rest of the experimental conditions. fERN differentiates between wins and losses, but changes in the size and probability of rewards impact the fERN amplitude only in win conditions. Results also show greater positivity following win feedback when the size and/or probability of the outcome rewards were higher, so that the higher the expected value the greater the positivity following win feedback. Our findings support the notion that both the probability and size of the offered rewards modulate the motivational value for the win feedback, this being also true for their interaction in an expected value fashion. (C) 2010 Elsevier Inc. All rights reserved.
Subliminal presentation of other faces (but not own face) primes behavioral and evoked cortical processing of empathy for pain
(ELSEVIER, 2011) Ibanez, Agustin; Hurtado, Esteban; Lobos, Alejandro; Escobar, Josefina; Trujillo, Natalia; Baez, Sandra; Huepe, David; Manes, Facundo; Decety, Jean
Current research on empathy for pain emphasizes the overlap in the neural response between the first-hand experience of pain and its perception in others. However, recent studies suggest that the perception of the pain of others may reflect the processing of a threat or negative arousal rather than an automatic pro-social response. It can thus be suggested that pain processing of other-related, but not self-related, information could imply danger rather than empathy, due to the possible threat represented in the expressions of others (especially if associated with pain stimuli). To test this hypothesis, two experiments considering subliminal stimuli were designed. In Experiment 1, neutral and semantic pain expressions previously primed with own or other faces were presented to participants. When other-face priming was used, only the detection of semantic pain expressions was facilitated. In Experiment 2, pictures with pain and neutral scenarios previously used in ERP and fMRI research were used in a categorization task. Those pictures were primed with own or other faces following the same procedure as in Experiment 1 while ERPs were recorded. Early (N1) and late (P3) cortical responses between pain and no-pain were modulated only in the other-face priming condition. These results support the threat value of pain hypothesis and suggest the necessity for the inclusion of own-versus other-related information in future empathy for pain research. (C) 2011 Elsevier B.V. All rights reserved.

Browsing by Author "Ibanez, Agustin"

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