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Can learning capacity of the human brain be predicted from initial spontaneous functional connectivity (FC) between brain areas involved in a task? We combined task-related functional magnetic resonance imaging (fMRI) and resting-state fMRI (rs-fMRI) before and after training with a Hindi dental–retroflex nonnative contrast. Previous fMRI results were replicated, demonstrating that this learning recruited the left insula/frontal operculum and the left superior parietal lobe, among other areas of the brain. Crucially, resting-state FC (rs-FC) between these two areas at pretraining predicted individual differences in learning outcomes after distributed (Experiment 1) and intensive training (Experiment 2). Furthermore, this rs-FC was reduced at posttraining, a change that may also account for learning. Finally, resting-state network analyses showed that the mechanism underlying this reduction of rs-FC was mainly a transfer in intrinsic activity of the left frontal operculum/anterior insula from the left frontoparietal network to the salience network. Thus, rs-FC may contribute to predict learning ability and to understand how learning modifies the functioning of the brain. The discovery of this correspondence between initial spontaneous brain activity in task-related areas and posttraining performance opens new avenues to find predictors of learning capacities in the brain using task-related fMRI and rs-fMRI combined. This work was supported in part by Spanish Ministerio de Ciencia e Innovacio/ńn Grants PSI2010-20168, PSI2012-/n34071, and CONSOLIDER-INGENIO 2010 Programme CDS-2007-00012, Generalitat Valenciana Grant APOSTD//n2012068, and Universitat Jaume I Grant P1-1B2012-38. G.D. was supported by the ERC Advanced Grant/nDYSTRUCTURE (no. 295129). by the Spanish Research Project SAF2010-16085, and by the CONSOLIDER-INGENIO/n2010 Program CSD2007-00012

The reinforcement sensitivity theory (RST) relates individual differences in reward sensitivity to the activation of the behavioral approach system (BAS). Dopamine-related brain structures have been repeatedly associated with reward processing, but also with cognitive processes such as task switching. In the present study, we examined the association between reward sensitivity and the event-related fMRI BOLD response with set switching in 31 males. As expected, the right inferior frontal cortex (rIFG) and the striatum (i.e. the left putamen) were involved in set-switching activity for the overall sample. Interindividual differences in Gray’s reward sensitivity were related to stronger activity in the rIFG and the ventral striatum. Thus, trait reward sensitivity contributed to the modulation of brain responsiveness in set-switching tasks. Having considered previous research, we propose that higher BAS activity is associated with a stronger reward to process a better implementation of goal-directed tasks and the diminished processing of secondary cues.

Ayahuasca is an Amazonian psychotropic plant tea typically obtained from two plants, Banisteriopsis caapi and Psychotria viridis. It contains the psychedelic 5-HT2A and sigma-1 agonist N,N-dimethyltryptamine (DMT) plus beta-carboline alkaloids with monoamine-oxidase (MAO)-inhibiting properties. Although the psychoactive effects of ayahuasca have commonly been attributed solely to agonism at the 5-HT2A receptor, the molecular target of classical psychedelics, this has not been tested experimentally. Here we wished to study the contribution of the 5-HT2A receptor to the neurophysiological and psychological effects of ayahuasca in humans. We measured drug-induced changes in spontaneous brain oscillations and subjective effects in a double-blind randomized placebo-controlled study involving the oral administration of ayahuasca (0.75 mg DMT/kg body weight) and the 5-HT2A antagonist ketanserin (40 mg). Twelve healthy, experienced psychedelic users (5 females) participated in four experimental sessions in which they received the following drug combinations: placebo + placebo, placebo +ayahuasca, ketanserin +placebo and ketanserin +ayahuasca. Ayahuasca induced EEG power decreases in the delta, theta and alpha frequency bands. Current density in alpha-band oscillations in parietal and occipital cortex was inversely correlated with the intensity of visual imagery induced by ayahuasca. Pretreatment with ketanserin inhibited neurophysiological modifications, reduced the correlation between alpha and visual effects, and attenuated the intensity of the subjective experience. These findings suggest that despite the chemical complexity of ayahuasca, 5-HT2A activation plays a key role in the neurophysiological and visual effects of ayahuasca in humans. (C) 2016 Elsevier B.V. and ECNP. All rights reserved.

A “disinhibited” cognitive profile has been proposed for individuals with high reward sensitivity, characterized by increased engagement in goal-directed responses and reduced processing of negative or unexpected cues, which impairs adequate behavioral regulation after feedback in these individuals. This pattern is manifested through deficits in inhibitory control and/or increases in RT variability. In the present work, we aimed to test whether this profile is associated with the activity of functional networks during a stop-signal task using independent component analysis (ICA). Sixty-one participants underwent fMRI while performing a stop-signal task, during which a manual response had to be inhibited. ICA was used to mainly replicate the functional networks involved in the task (Zhang and Li, 2012): two motor networks involved in the go response, the left and right fronto-parietal networks for stopping, a midline error-processing network, and the default-mode network (DMN), which was further subdivided into its anterior and posterior parts. Reward sensitivity was mainly associated with greater activity of motor networks, reduced activity in the midline network during correct stop trials and, behaviorally, increased RT variability. All these variables explained 36% of variance of the SR scores. This pattern of associations suggests that reward sensitivity involves greater motor engagement in the dominant response, more distractibility and reduced processing of salient or unexpected events, which may lead to disinhibited behavior. This study was supported by grants from MINECO (PSI2013-45378-R, PSI2012-33054 and CSD2007-00012), the Spanish National Drug Strategy of the Spanish Ministry of Health and Consumption (4623/2011), the Generalitat Valenciana (GV/2012/042) and Universitat Jaume I (P1-1A2010-01 and P1·1B2013-63). PFC was supported by a FPU fellowship from the Spanish Ministry of Education (AP-2010-6060).

High reward sensitivity has been linked with motivational and cognitive disorders related with prefrontal and striatal brain function during inhibitory control. However, few studies have analyzed the interaction among reward sensitivity, task performance and neural activity. Participants (N = 57) underwent fMRI while performing a Go/No-go task with Frequent-go (77.5%), Infrequent-go (11.25%) and No-go (11.25%) stimuli. Task-associated activity was found in inhibition-related brain regions, with different activity patterns for right and left inferior frontal gyri (IFG): right IFG responded more strongly to No-go stimuli, while left IFG responded similarly to all infrequent stimuli. Reward sensitivity correlated with omission errors in Go trials and reaction time (RT) variability, and with increased activity in right and left IFG for No-go and Infrequent-go stimuli compared with Frequent-go. Bilateral IFG activity was associated with RT variability, with reward sensitivity mediating this association. These results suggest that reward sensitivity modulates behavior and brain function during executive control. This research has been supported by the Brainglot Project of the 2010 CONSOLIDER-INGENIO Program (CSD2007-00012), and also by grants from MINECO (PSI2012-33054), the Spanish National Drug Strategy (4623/2011), the Spanish Ministry of Health and Consumption, the Generalitat Valenciana (GV/2012/042) and the Universitat Jaume I (P1-1A2010-01) to A. Barrós-Loscertales.

Research has shown that semantic processing of sentences engages more activity in the bilingual compared to the monolingual brain and, more specifically, in the inferior frontal gyrus. The present study aims to extend those results and examines whether semantic and also grammatical sentence processing involve different cerebral structures when testing in the native language. In this regard, highly proficient Spanish/Catalan bilinguals and Spanish monolinguals made grammatical and semantic judgments in Spanish while being scanned. Results showed that both types of judgments recruited more cerebral activity for bilinguals in language-related areas including the superior and middle temporal gyri. Such neural differences co-occurred with similar performance at the behavioral level. Taken together, these data suggest that early bilingualism shapes the brain and cognitive processes in sentence comprehension even in their native language; on the other hand, they indicate that brain over activation in bilinguals is not constrained to a specific area. This research was supported by Research Grants PSI 2009-10067 and PSI 2014-47604-R (Ministry of Science and Innovation of Spain) and by BRAINGLOT, a Spanish Research Network on Bilingualism and Cognitive Neuroscience (CSD2007-00012, Consolider-Ingenio 2010 Scheme, Ministry of Science and Technology of Spain).

The existence of a behavioral advantage of bilinguals over monolinguals during executive tasks is controversial. A new approach to this issue is to investigate the effect of bilingualism on neural control when performing these tasks as a window to understand when behavioral differences are produced. Here, we tested if early bilinguals use more language-related networks than monolinguals while performing a go/no-go task that includes infrequent no-go and go trials. The RTs and accuracy in both groups did not differ. An independent component analyses (ICA) revealed, however, that bilinguals used the left fronto-parietal network and the salience network more than monolinguals while processing go infrequent cues and no-go cues, respectively. It was noteworthy that the modulation of these networks had opposite correlates with performance in bilinguals and monolinguals, which suggests that between-group differences were more qualitative than quantitative. Our results suggest that bilinguals may differently develop the involvement of the executive control networks that comprise the left inferior frontal gyrus during cognitive control tasks than monolinguals MINECO . Grant Number: PSI2013-47504-R and CSD2007-0012 Universitat Jaume I . Grant Number: P1•1B2013-63

Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies. Brainglot Project of the CONSOLIDER-INGENIO Program CSD2007-00012 MINECO PSI2012-33054 Spanish National Drug Strategy 4623/2011 Spanish Ministry of Health and Consumption Generalitat Valenciana GV/2012/042 Universitat Jaume I P1-1A2010-01

[EN] Background: To date, still images or videos of real animals have been used in functional magnetic resonance imaging protocols to evaluate the brain activations associated with small animals phobia. Objective: The objective of our study was to evaluate the brain activations associated with small animals phobia through the use of virtual environments. This context will have the added benefit of allowing the subject to move and interact with the environment, giving the subject the illusion of being there. Methods: We have analyzed the brain activation in a group of phobic people while they navigated in a virtual environment that included the small animals that were the object of their phobia. Results: We have found brain activation mainly in the left occipital inferior lobe (P, This study was funded by Vicerrectorado de Investigación de la Universitat Politècnica de València, Spain, PAID-06-2011, RN 1984; by the Ministerio de Educación y Ciencia Spain, Project Game Teen (TIN2010-20187); and partially by projects Consolider-C (SEJ2006-14301/PSIC), “CIBER of Physiopathology of Obesity and Nutrition, an initiative of ISCIII”, the Excellence Research Program PROMETEO (Generalitat Valenciana. Conselleria de Educación, 2008-157), and the Consolider INGENIO program (CSD2007-00012). Generalitat Valenciana, under a VALi+d Grant, supported the work of MC.

We tested the hypothesis that early bilinguals and monolinguals use different brain areas when performing nonlinguistic executive control tasks. For this, we explored brain activity of early bilinguals and monolinguals during a manual stop-signal paradigm. Behaviorally, bilinguals and monolinguals did not show significant differences in the task, which led us to compare brain activation that cannot be attributed to differences in performance. Analyses demonstrated that monolinguals activated the anterior cingulate cortex more than bilinguals when performing the stop-signal task. These results offer direct support for the notion that early bilingualism exerts an effect on neural circuitry responsible for executive control. Consistent with recent reports, we found that bilinguals used the anterior cingulate more efficiently than monolinguals to monitor nonlinguistic cognitive conflicts.

INTRODUCCIÓN En los últimos años se ha producido un vertiginoso aumento de la población bilingüe que, inevitablemente, ha propiciado la aparición de múltiples preguntas acerca de los efectos colaterales del bilingüismo. Dichos efectos se han estudiado, tanto en los procesos que implican procesamiento del lenguaje como en aquellos no directamente relacionados con el mismo. Teniendo en cuenta resultados de investigaciones previas, existirían diferencias en el procesamiento del lenguaje que bilingües y monolingües llevan a cabo. Dichas diferencias, halladas tanto a nivel conductual como cerebral, parecen indicar que el bilingüe ejerce un constante control cognitivo de sus dos lenguas cuando realiza procesos de lenguaje, para evitar la interferencia de la lengua no deseada. Así, los bilingües serían ligeramente menos eficaces que los monolingües en la realización de algunas tareas lingüísticas, debido a la necesidad de emplear ciertos recursos cognitivos para resolver los conflictos entre ambas lenguas. Sin embargo, estudios con tareas de control cognitivo no lingüístico han evidenciado ciertas ventajas conductuales (en TR y número de aciertos) en los bilingües cuando se los compara con los monolingües. Por otra parte, estudios cerebrales sobre el control del lenguaje indicarían que los bilingües activan una extensa red cerebral (integrada por áreas corticales y subcorticales) que también intervendría en el control lingüístico del monolingüe pero que, ajustándose a las mayores demandas del bilingüe, generaría ciertas diferencias en el procesamiento del lenguaje de ambos grupos. Dicho esfuerzo se ha manifestado en forma de distintas activaciones: en el córtex prefrontal, que se reducirían a medida que aumentase la habilidad y se automatizasen los procesos implicados; en el cingulado anterior, asociado con la detección del conflicto entre lenguas; en el caudado, por la inhibición de la lengua no deseada; en el córtex parietal, vinculadas al mantenimiento de las representaciones de la memoria de trabajo; en áreas temporales, relacionadascon el feedback auditivo-motor de la respuesta articulatoria; etc. Esta red no tendría una función específica de control lingüístico, sino que ejercería esta función junto con otras funciones de control cognitivo. tareas de control cognitivo comparando ambos grupos. Y éste es precisamente el aspecto abordado en esta tesis: la detección de diferencias cerebrales entre bilingües y monolingües cuando realizan tareas de control cognitivo no lingüísticas. Más concretamente, se pretende avanzar en el conocimiento de los efectos del bilingüismo tanto en los procesos inhibitorios, mediante una Sin embargo, apenas se han realizado estudios cerebrales en tarea de señal de stop manual, como en otros de alternancia, mediante dos paradigmas de alternancia entre tareas no lingüísticas, una con la implicación mecanismos de control cognitivo reactivos y otra con mecanismos de control proactivos (el proactivo implicaría procesos cognitivos tempranos y sostenidos, durante la realización de tareas sencillas y la planificación de acciones nuevas; mientras que el reactivo implicaría procesos de corrección, tardíos y transitorios activados precipitadamente tras la detección de un estímulo, en tareas con altas demandas de control cognitivo y manejo de acciones familiares). La hipótesis global de trabajo sería comprobar si los bilingües tempranos y proficientes, debido a la continua necesidad de manejar las dos lenguas que utilizan, desarrollan una forma diferente de control cognitivo en tareas no lingüísticas. Esta forma diferente se manifestaría en un mayor uso de áreas lingüísticas en bilingües que en monolingües durante la ejecución de estas tareas. METODOLOGÍA La sección experimental de esta tesis está compuesta por 3 estudios. Dos de ellos han sido publicados en una revista de alto impacto (Garbin G., Sanjuan A., Forn C., Bustamante JC., Rodríguez-Pujadas A., Belloch V., Hernandez M., Costa A., Ávila C (2011) Bridging language and attention: Brain basis of the impact of bilingualism on cognitive control. Neuroimage, 119: 129-135; Rodríguez-Pujadas, A., Sanjuán, A., Ventura-Campos, N., Román, P., Martin, C., Barceló, F., Costa, A., Ávila, C (2013) Bilinguals use language-control brain areas more than monolinguals to perform non-linguistic switching tasks. Plos One) y el tercero y último está actualmente bajo revisión. Todos los estudios han sido realizados con una muestra de estudiantes de la Universitat Jaume I de Castellón, de edades comprendidas entre los 20 y los 23 años. La muestra de bilingües está formada por bilingües tempranos y proficientes, es decir, que han tenido un contacto diario y desde la infancia (con un contacto inicial, como máximo, desde los 3 años de edad) con el catalán, haciendo un uso activo de ambas lenguas durante toda su vida y, en consecuencia, recurriendo a la frecuente realización de cambios entre lenguas de manera diaria. Este punto es de crucial importancia, porque la realización de dichos cambios entre lenguas, de manera frecuente y a lo largo de toda la vida, afectaría al desarrollo y funcionamiento del sistema de control ejecutivo, generando diferencias con los monolingües que no realizan dichos cambios. Por otro lado, la muestra de monolingües, está formada por jóvenes universitarios que, habiendo crecido en una comunidad autónoma con una única lengua oficial (el castellano) se han trasladado a Castellón (por motivo de estudios, en la misma universidad), llevando como máximo un año viviendo en Castellón. Todos los participantes rellenaban una serie de cuestionarios en los que se evaluaba su nivel de habilidad lingüística así como su contacto con ambas lenguas en distintos ámbitos vitales. Para ello, se utilizaba el Cuestionario de Uso de las Lenguas y otro de frecuencia de uso. Además, para verificar (desde un punto de vista aplicado) su nivel de comprensión o domino de ambas lenguas, eran sometidos a una entrevista personal. CONCLUSIONES Del desarrollo de los estudios que integran esta tesis se pueden extraer las siguientes conclusiones: 1) Los hablantes bilingües y monolingües activan áreas cerebrales distintas cuando llevan a cabo procesos de control cognitivo no lingüístico. 2)En la mayoría de los casos, dichas diferencias cerebrales no implican diferencias a nivel conductual, lo que permite concluir que la diferente organización cerebral no siempre va asociada con ventajas conductuales. 3) Desde una perspectiva global, los resultados evidencian que para realizar tareas de control cognitivo no relacionadas con el lenguaje, los bilingües activan en mayor grado áreas de control del lenguaje (giro frontal inferior izquierdo y caudado izquierdo), mientras que los monolingües evidencian un mayor uso de áreas de procesamiento cognitivo y resolución del conflicto (córtex cingulado anterior). 4) Los resultados apoyan la hipótesis de que el procesamiento del lenguaje en el bilingüe ejerce efectos colaterales en el sistema general de control cognitivo, que tiende a un mayor uso de áreas del lenguaje para llevar a cabo funciones de control cognitivo no relacionadas con el lenguaje.

Language fMRI has been used in the presurgical evaluation of drug-resistant temporal lobe epilepsy patients. Previous studies have demonstrated that left temporal lobe epilepsy (LTLE) patients with atypical language lateralization are at lower risk of postsurgical verbal memory decline, hypothesizing co-occurrence of verbal memory and language reorganization presurgically. Furthermore, it has been proposed that the recruitment of right frontal language-related areas is associated with the preservation of verbal memory performance in these patients. However, less is known about the correlation between these functions specifically in LTLE patients with left language dominance, although they are more prone to postsurgical verbal memory decline. The aim of the present study was to investigate whether the relationship between verbal memory scores and frontal language activation is also observed in LTLE patients with typical language dominance. Eighteen healthy controls, 12 right temporal lobe epilepsy patients and 12 LTLE patients with typical language distribution as assessed by an fMRI verbal fluency task were selected. Verbal memory scores were obtained from the patients' neuropsychological presurgical evaluation. Our results showed a positive correlation between verbal recall and activation of bilateral inferior frontal areas in LTLE patients. These results support the hypothesis of a link between language representation in inferior frontal areas and hippocampal functioning, and indicate that both hemispheres are related to the preservation of verbal memory in patients with hippocampal damage and typical language dominance.

The left inferior frontal cortex, the caudate and the anterior cingulate have been proposed as the neural origin of language switching, but most of the studies were conducted in low proficient bilinguals. In the present study, we investigated brain areas involved in language switching in a sample of 19 early, high-proficient Spanish–Catalan bilinguals using a picture naming task that allowed contrasting switch and non-switch trials. Compared to the non-switching condition, language switching elicited greater activation in the head of the left caudate and the pre-SMA/ACC. When the direction of the switching was considered, the left caudate was more associated with forward switching and the pre-SMA/ACC with backward switching. The discussion is focused on the relevance of these brain structures in language control in early, high-proficient bilinguals, and the comparison with previous results in late bilinguals. This study was supported by two grants of the Spanish Ministry of Science and Technology given to Cesar Avila [the BrainGlot Project, CSD2007-00012 (funded by the Consolider-Ingenio 2010 programme), and the grant PSI2010-20168 and two grants given to Albert Costa (PSI2008-01191 from the MICINN and SGR 2009-1521 from the Catalan Government)

To test the capacity of a sentence verification (SV) task to reliably activate receptive language areas. Presurgical evaluation of language is useful in predicting postsurgical deficits in patients who are candidates for neurosurgery. Productive language tasks have been successfully elaborated, but more conflicting results have been found in receptive language mapping.Twenty-two right-handed healthy controls made true-false semantic judgements of brief sentences presented auditorily.Group maps showed reliable functional activations in the frontal and temporoparietal language areas. At the individual level, the SV task showed activation located in receptive language areas in 100% of the participants with strong left-sided distributions (mean lateralisation index of 69.27).The SV task can be considered a useful tool in evaluating receptive language function in individual subjects. This study is a first step towards designing the fMRI task which may serve to presurgically map receptive language functions.

Drug and Alcohol Dependence 156 (2015) e183–e245 e189 areas of sexual risk reduction, prevention and treatment for substanceabuseandmental health. Publichealthprogramsprioritizing the different populations are necessary. Financial support: Fogarty International Center; Grant 1R03TW007612; Fundo de Incentivo e Auxilio a Pesquisa (FIPE) from Hospital de Clinicas de Porto Alegre, Brazil (GPPGHCPA – No. 07-391). http://dx.doi.org/10.1016/j.drugalcdep.2015.07.507 Crack, powdered cocaine, both or neither: A generalized logit analysis of a community-based sample Grace L. Reynolds1,2,∗, Dennis G. Fisher1, Erlyana Erlyana2 1 Center for Behavioral Research and Services, California State University, Long Beach, Long Beach, CA, United States 2 Health Care Administration, California State University, Long Beach, Long Beach, CA, United States Aims: To understand factors associated with use of both crack cocaine and non-injected powered cocaine. Methods: The Risk Behavior Assessment (RBA; 1993) was used to elicit information on past month, past 48-hours and drugs used before/during sex drug use in a sample of out-of-treatment drug users (N=8538). Past 30 day, past 48h, and before/during sex drug use were coded into (1) use of crack (smokable cocaine) only, (2) powdered cocaine use only, (3) both drugs used during the timeframe and (4) neither drug used. Generalized logit analysis was used to develop models for each timeframe (48-hour and 30-day). For all models the reference group was using neither drug. Results: Respondents who reported use of both crack and powdered cocaine (N=306) included both men (n=207) and women (n=99). The 48-hour, 30-day, and before/during sex models were almost identical. Those who reported using both crack and cocaine were more likely to: be Black (OR=1.65, CI 1.27, 2.14); bisexual (OR=1.85, CI 1.39, 2.47); trade sex fordrugs (OR=4.88CI 3.73, 6.39); tobehomeless (OR=3.50, CI 2.66, 4.62), havehighernumberof days used alcohol in the pastmonth (OR=1.09, CI 1.08, 1.10); and to have had gonorrhea (OR=1.42, CI 1.07, 1.88). Conclusions: The general logit model highlights factors associated with use of both crack and powdered cocaine within the same timeframe, includinghomelessness, andbeingamemberof anethic or sexual minority, and sex trading. Financial support: Funding was provided in part by grant R01 DA030234 from the National Institute on Drug Abuse, P20MD003942 from the National Institute of Minority Health and Health Disparities. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Drug Abuse, the National Institute ofMinority Health and Health Disparities or the National Institutes of Health. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.508 Cannabis users show increased susceptibility to false memories Jordi Riba1,∗, Frederic Sampedro2, Aina Rodriguez-Pujadas2, Saul Martinez-Horta1, Jaime Kulisevsky1, Jose-Carlos Perez-de-los-Cobos1, Antoni Rodriguez-Fornells1, Marta Valle1 1 Hospital Sant Pau, Barcelona, Spain 2 University of Barcelona, Barcelona, Spain Aims: Previous studies on the neurocognitive impact of cannabis use have found working and declarative memory deficits that tend to normalize with abstinence. An unexplored aspect of cognitive function in chronic cannabis users is the ability to distinguish between veridical and illusory events; a crucial aspect of reality monitoring that relies on adequate memory function and cognitive control. Methods: Sixteen heavy cannabis users not seeking treatment for their cannabis consumptionwerematched to a group of healthy controls taking into account sex, age, years of education, verbal intelligence and fluid intelligence. All participants performed a modified version of the Deese–Roediger–McDermott paradigm in an MRI scanner. Following a study phase, subjects were presented with 75 old words, 40 semantically unrelated new words and 40 semantically related new words or lures. They were required to judge whether a word had been presented in the study phase and make an old vs. new decision by button press. Results: Cannabis users showed an increased susceptibility to false memories, failing to identify lure stimuli as events that never occurred. In addition to impaired performance, they displayed reduced activation in areas associated with memory processing within the medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring. Reduced activity in the MTL was associated with greater cannabis consumption. Conclusions: These findings indicate that cannabis users have an increased susceptibility to memory distortions even when abstinent and drug-free, suggesting a long-lasting compromise of memory and cognitive control mechanisms involved in reality monitoring. Financial support: This research was supported by the “Plan Nacional Sobre Drogas” of the Spanish Government. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.509 CaMKII inhibition affects cocaine-cue memory processes to attenuate reinstatement Matthew T. Rich1,∗, Mary M. Torregrossa2 1 University of Pittsburgh, Pittsburgh, PA, United States 2 Psychiatry, University of Pittsburgh, Pittsburgh, PA

The aim of this work was to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and brain activity during task switching. BAS sensitivity was hypothesized to modulate activity in brain regions involved in cognitive flexibility, including anterior cingulate, dorsolateral prefrontal cortex, inferior frontal gyrus and striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task devised by Barcelo et al. (2008). BAS sensitivity was measured with the Sensitivity to Reward (SR) scale from the SPSRQ (Torrubia et al., 2001). The task yielded the expected behavioral switch costs and brain activity in fronto-striatal regions associated with the switching cue. SR scores were negatively associated with brain activity during task switching in dorsolateral prefrontal cortex, anterior cingulate and right anterior insula. These results indicate that BAS sensitivity may modulate cognitive processes occurring in brain areas commonly involved in attention, working memory and cognitive flexibility.

This work investigated the relationship between individual differences in reward sensitivity and the activity of brain regions involved in response inhibition. Participants (n = 51, 20 females) performed a stop-signal task while undergoing fMRI scanning. Inhibition of dominant responses during the task was associated to activation of bilateral anterior insula. Parameter estimates from these activation clusters were extracted to run an ROI analysis. Reward sensitivity, as measured by the Sensitivity to Reward (SR) scale from the SPSRQ (Torrubia et al., 2001), was negatively correlated with activity in right anterior insula. A whole-brain correlation analysis was also conducted, in which SR scores were negatively correlated with activity in the anterior cingulate cortex and the left supramarginal gyrus. These results suggest that individual differences in reward sensitivity may involve differences in cognitive processing that are manifested as distinct patterns of brain activation, even in the absence of explicit reward contingencies.