Recollection and familiarity for words and faces: a study comparing Remember-Know judgements and the Process Dissociation Procedure.

Measures of recollection and familiarity often differ depending on the paradigm utilised. Remember-Know (R-K) and Process Dissociation Procedure (PDP) methods have been commonly used but rarely compared within a single study. In the current experiments, R-K and PDP were compared by examining the effect of attention at study and time to respond at test on recollection and familiarity using the same experimental procedures for each paradigm. We also included faces in addition to words to test the generality of the findings often obtained using words. The results from the R-K paradigm revealed that recollection and familiarity were similarly affected by attention at study and time to respond at test. However, in the case of PDP, the measures of recollection and familiarity showed a different pattern of results. The effects observed for recollection were similar to those obtained with the R-K method, whereas familiarity was affected by time to respond but not by attention at study. These results are discussed in relation to the controlled-automatic processing distinction and the contribution of each paradigm to research on recognition memory.

Unconscious biases in task choices depend on conscious expectations.

Recent studies highlight the influence of non-conscious information on task-set selection. However, it has not yet been tested whether this influence depends on conscious settings, as some theoretical models propose. In a series of three experiments, we explored whether non-conscious abstract cues could bias choices between a semantic and a perceptual task. In Experiment 1, we observed a non-conscious influence on task-set selection even when perceptual priming and cue-target compound confounds did not apply. Experiments 2 and 3 showed that, under restrictive conditions of visibility, cues only biased task selection when the conscious task-setting mindset led participants to search for information during the time period of the cue. However, this conscious strategy did not modulate the effect found when a subjective measure of consciousness was used. Altogether, our results show that the configuration of the conscious mindset determines the potential bias of non-conscious information on task-set selection.

Ignoring facial emotion expressions does not eliminate their influence on cooperation decisions / Ignorar las emociones de otros no evita su efecto en nuestras decisiones cooperativas

Whereas the automaticity of emotion processing has been investigated in several cognitive domains, its mandatory influence on cooperative decision-making is still unexplored. We employed an interference-task to evaluate whether explicit instructions to ignore the emotions of others during alleged interpersonal interactions override their behavioral effects. Participants played a Trust Game multiple times with eight cooperative or non-cooperative partners, who displayed facial expressions of happiness or anger. Emotions were non-predictive regarding the partners’ cooperation. In Experiments 1 and 2 participants were explicitly asked to ignore the emotions, and the uncertainty about the partners’ behavior varied. We found an effect of emotional interference; whereas happy partners speeded cooperative decisions, angry ones speeded non-cooperative choices. This was replicated in Experiment 3, where the request of ignoring emotions was removed. Our results show the inevitable influence of the emotional displays of others during cooperation decisions, which fits with theories that contend for a tight link between emotions and social context (AU)

Pese a que la influencia ejercida por el procesamiento de las emociones ha sido estudiada en diferentes dominios cognitivos, el papel de estas durante la toma decisiones en contextos sociales queda aún por explorar. Utilizamos una tarea de interferencia con el fin de estudiar en qué grado es posible evitar la influencia de las emociones de otras personas cuando nos encontramos en interacción con ellas. Los participantes jugaron, en múltiples rondas, al Juego de la Confianza con ocho compañeros que podían ser de tipo cooperativo o no cooperativo, y cuya expresión facial podía ser de felicidad o de enfado. Las emociones de los compañeros de juego no eran predictivas, en ningún caso, de su grado de cooperación. Tanto en el Experimento 1 como en el Experimento 2 los participantes fueron instruidos de manera explícita que debían ignorar las expresiones emocionales de sus compañeros. La validez de la información personal (el grado de cooperación) fue manipulada entre ambos expresultados revelaron un efecto de interferencia emocional; las expresiones de felicidad redujeron el tiempo necesario para tomar la decisión de cooperación, mientras que las expresiones de enfado acortaron las decisiones de no cooperación. Este efecto de interferencia fue replicado en el Experimento 3, en el que la instrucción explícita de ignorar las emociones de los compañeros había sido eliminada.Nuestros resultados muestran que las emociones de otros nos influyen de manera inevitable durante nuestra interacción con ellos. Esta evidencia es coherente con las teorías que defienden la existencia de un estrecho vínculo entre emociones y contexto social (AU)

Resonancia magnética funcional: análisis crítico de sus implicaciones técnicas, estadísticas y teóricas en neurociencia humana / Functional magnetic resonance imaging: a critical analysis of its technical, statistical and theoretical implications in human neuroscience

Introducción. La utilización de la resonancia magnética funcional (RMf) ha supuesto una gran revolución en el avance de las neurociencias. Pese a ello, ha sido objeto de numerosas críticas. Objetivo. Estudiar las críticas más generalizadas hacia la RMf, de manera que investigadores que se inicien en su uso conozcan los diferentes elementos que hay que tener en cuenta para un acercamiento adecuado a esta técnica. Desarrollo. Su gran atractivo y utilidad a la hora de observar la actividad cerebral han hecho de la RMf una técnica cuyo uso ha crecido exponencialmente desde la última década del siglo XX. Paralelamente, la crítica hacia ella ha sido especialmente feroz. La mayoría de este escepticismo puede clasificarse en aspectos concernientes a la técnica y fisiología, el análisis de los datos y su interpretación teórica. Mediante este trabajo se revisarán los principales argumentos en cada uno de estos tres apartados, así como su adecuación. Adicionalmente, se pretende que este trabajo pueda servir de referencia para investigadores noveles a la hora de identificar elementos que se deban tener en cuenta en su acercamiento a la RMf. Conclusión. Pese a que la RMf constituye actualmente una de las opciones más interesantes para observar el cerebro, es necesario un alto grado de control y conocimiento para su utilización. Aun así, gran parte de las críticas no se sostiene hoy en día (AU)

Introduction. The use of functional magnetic resonance imaging (fMRI) has represented an important step forward for the neurosciences. Nevertheless, it has also been subject to rather a lot of criticism. AIM. To study the most widespread criticism against fMRI, so that researchers who are starting to use it may know the different elements that must be taken into account to be able to take a suitable approach to this technique. Development. The fact that fMRI allows brain activity to be observed makes it a very attractive and useful tool, and its use has grown exponentially since the last decade of the 20th century. At the same time, criticism against its use has become especially fierce. Most of this scepticism can be classified into aspects related with the technique and physiology, the analysis of data and their theoretical interpretation. In this study we will review the main arguments defended in each of these three areas, as well as looking at whether they are well-founded or not. Additionally, this work is also intended as a reference for novel researchers when it comes to identifying elements that must be taken into account as they approach fMRI. Conclusions. Despite the fact that fMRI is one of the most interesting options for observing the brain available today, its correct utilisation requires a great deal of control and knowledge. Even so, today most of the criticism it receives no longer has any solid foundation on which to stand (AU)

Cognitive and affective control in a flanker word task: common and dissociable brain mechanisms.

In the present study we compared the nature of cognitive and affective conflict modulations at different stages of information processing using electroencephalographic recordings. Participants performed a flanker task in which they had to focus on a central word target and indicate its semantic category (cognitive version) or its valence (affective version). Targets were flanked by congruent or incongruent words in both versions. Although tasks were equivalent at the behavioral level, event-related potentials (ERPs) showed common and dissociable cognitive and emotional conflict modulations. At early stages of information processing, both tasks generated parallel sequential conflict effects in the P1 and N170 potentials. Later, the N2 and the first part of the P3 wave were exclusively modulated by cognitive conflict, whereas the last section of the P3 deflection/Late Positive Component (LPC) was only involved in affective current conflict processing. Therefore, the whole data set suggests the existence of early common mechanisms that are equivalent for cognitive and affective materials and later task-specific conflict processing.

Interactions between perceived emotions and executive attention in an interpersonal game.

The emotions displayed by others can be cues to predict their behavior. Happy expressions are usually linked to positive consequences, whereas angry faces are associated with probable negative outcomes. However, there are situations in which the expectations we generate do not hold. Here, control mechanisms must be put in place. We designed an interpersonal game in which participants received good or bad economic offers from several partners. A cue indicated whether the emotion of their partner could be trusted or not. Trustworthy partners with happy facial expressions were cooperative, and angry partners did not cooperate. Untrustworthy partners cooperated when their expression was angry and did not cooperate when they displayed a happy emotion. Event-Related Potential (ERP) results showed that executive attention already influenced the frontal N1. The brain initially processed emotional expressions regardless of their contextual meaning but by the N300, associated to affective evaluation, emotion was modulated by control mechanisms. Our results suggest a cascade of processing that starts with the instantiation of executive attention, continues by a default processing of emotional features and is then followed by an interaction between executive attention and emotional factors before decision-making and motor stages.

Emotional conflict in interpersonal interactions.

Facial displays of emotions can help to infer the mental states of other individuals. However, the expectations we generate on the basis of people's emotions can mismatch their actual behaviour in certain circumstances, which generates conflict. In the present study, we explored the neural mechanisms of emotional conflict during interpersonal interactions. Participants had to accept or reject economic offers made by several partners who displayed emotional expressions. On every trial, a cue informed participants of whether they could trust the emotion of their partner or not. Trustworthy (low-conflict) partners with happy facial expressions were cooperative and those with angry expressions did not cooperate. Untrustworthy (high-conflict) partners, on the other hand, cooperated when their expression was angry and did not cooperate when they displayed a happy emotion. Behavioural responses were faster for trustworthy than for untrustworty partners. High-conflict partners activated the anterior cingulate and the anterior insula. In turn, trustworthy partners were associated with activations in the left precuneus. Our results suggest that the emotion displayed by another person affects our decision-making in social contexts. When emotional expressions are linked to their natural consequences, they engage ToM processes. In contrast, untrustworthy emotional expressions engage conflict-related brain regions.

Focusing on the bodily self: the influence of endogenous attention on visual body processing.

The present study explores whether endogenous attention can modulate body perception. A modified version of the Posner paradigm was used to direct participants' attention toward the appearance of distinct body images, which differed only in detailed idiosyncratic features: one's own and another person's hands. Hand stimuli were preceded by symbolic cues that predicted their identity with high probability, which made it possible to compare the processing of expected (valid) and unexpected (invalid) targets. Results revealed that endogenous attention influenced the processing of participants' own hands by speeding participants' responses to valid in contrast to invalid trials. Crucially, no validity effect was found for the hands of another person. These findings cannot be explained in terms of perceptual familiarity, since an optimization of the processing for both familiar and unfamiliar faces by symbolic cues was observed. In light of these results, it is suggested that participants are able to anticipate particular stimuli within the same perceptual category as long as these stimuli appear to be remarkably distinct to them, which is probably the case for particular faces and their own bodies, in contrast to other people's bodies.

Category expectations: a differential modulation of the N170 potential for faces and words.

The goal of the present study was to explore whether endogenous attention can be oriented to different perceptual categories and to examine how these expectations modulate visual stimulus processing. We designed a cueing paradigm that prepared participants, on a trial-by-trial basis, for the most likely stimulus category of the target, which could be either a face or a word. Participants were asked to discriminate the gender of the stimuli, regardless of their category. We measured participants' brain activity by means of a high-density electroencephalographic recording system to investigate the neural correlates of orienting attention to faces and words. As expected, we observed a behavioural facilitation for valid compared to invalid trials. In addition, target expectations influenced stimulus processing at several points in time. Most importantly, attention modulated the lateralized N170 component in a category-specific fashion. These results show that, at least under certain circumstances, orienting endogenous attention to different categories can influence the perceptual stages of face and word visual processing.

What does the brain tell us about the mind?

El presente artículo explora larelevancia que tienen los datos del cerebro en la generación de teorías sobrela mente humana. En la era de la Ciencia Cognitiva, se asumía que elconocimiento sobre el cerebro y la mente corresponden a dos niveles deanálisis diferentes. Dicha independencia condujo al argumento epistémicode que el conocimiento acerca de las bases biológicas de la cogniciónhumana no es relevante para las explicaciones psicológicas. Hoy en día, sinembargo, las tecnologías de neuroimagen son una vía excepcional paraexplorar el funcionamiento cognitivo del cerebro. Los autores defienden queesta revolución tecnológica está asociada a una nueva manera de construirteorías sobre la cognición humana, en la que la mente y el cerebro no seconsideran autónomos ni independientes el uno del otro. Al contrario, laNeurociencia Cognitiva se caracteriza por un intercambio continuo ybidireccional de información entre la biología y cognición humanas

The present paper explores the relevance that brain data have in constructingtheories about the human mind. In the Cognitive Science era it was assumedthat knowledge of the mind and the brain correspond to different levels ofanalysis. This independence among levels led to the epistemic argument thatknowledge of the biological basis of cognition would not be relevant at apsychological level of explanation. Nowadays, however, modernneuroimaging technologies offer a powerful means to explore the cognitivefunctioning of the human brain. The authors argue that this technologicalrevolution is associated with a new way of building theories of humancognition in which mind and brain are no longer independent norautonomous. In contrast, the Cognitive Neuroscience era is marked by acontinuous and bi-directional exchange of information between biology andcognition

Temporal attention enhances early visual processing: a review and new evidence from event-related potentials.

Two fundamental cognitive functions, selective attention and processing of time, have been simultaneously explored in recent studies of temporal orienting of attention. A temporal-orienting procedure may consist of a temporal analogue to the Posner's paradigm, such that symbolic cues indicate the most probable moment for target arrival. Behavioral measures suggest that performance is improved for events appearing at expected vs. unexpected moments. However, there is no agreement on the locus of stimulus processing at which temporal attention operates. Thus, it remains unclear whether early perceptual or just late motor processes can be modulated. This article reviews current ERP research on temporal orienting, with an emphasis on factors that might determine the modulation of temporal orienting at early stages of processing. We conclude that: First, late components (N2 and P300) are consistently modulated by temporal orienting, which suggests attentional preparation of decision and/or motor processes. Second, early components (e.g., N1) seem to be modulated only when the task is highly demanding in perceptual processing. Hence, we conducted an ERP experiment which aimed to observe a modulation of early visual processing by using a perceptually demanding task, such as letter discrimination. The results show, for the first time, that targets appearing at attended moments elicited a larger P1 component than unattended targets. Moreover, temporal attention modulated the amplitude and latency of N2 and P300 components. This suggests that temporal orienting of attention not only modulates late motor processing, but also early visual processing when perceptually demanding tasks are used.

Selective temporal attention enhances the temporal resolution of visual perception: Evidence from a temporal order judgment task.

We investigated whether attending to a particular point in time affects temporal resolution in a task in which participants judged which of two visual stimuli had been presented first. The results showed that temporal resolution can be improved by attending to the relevant moment as indicated by the temporal cue. This novel finding is discussed in terms of the differential effects of spatial and temporal attention on temporal resolution.

The attentional mechanism of temporal orienting: determinants and attributes.

A review of traditional research on preparation and foreperiod has identified strategic (endogenous) and automatic (exogenous) factors probably involved in endogenous temporal-orienting experiments, such as the type of task, the way by which temporal expectancy is manipulated, the probability of target occurrence and automatic sequential effects, yet their combined impact had not been investigated. These factors were manipulated within the same temporal-orienting procedure, in which a temporal cue indicated that the target could appear after an interval of either 400 or 1,400 ms. We observed faster reaction times for validly versus invalidly cued targets, that is, endogenous temporal-orienting effects. The main results were that the probability of target occurrence (catch-trial proportion) modulated temporal orienting, such that the attentional effects at the short interval were independent of catch trials, whereas at the long interval the effects were only observed when catch trials were present. In contrast, the interval duration of the previous trial (i.e., exogenous sequential effects) did not influence endogenous temporal orienting. A flexible and endogenous mechanism of attentional orienting in time can account for these results. Despite the contribution of other factors, the use of predictive temporal cues was sufficient to yield attentional facilitation based on temporal expectancy.

Attentional preparation based on temporal expectancy modulates processing at the perceptual level.

Research that uses simple response time tasks and neuroimaging has emphasized that attentional preparation based on temporal expectancy modulates processing at motor levels. A novel approach was taken to study whether the temporal orienting of attention can also modulate perceptual processing. A temporal-cuing paradigm was used together with a rapid serial visual presentation procedure, in order to maximize the processing demands of perceptual analysis. Signal detection theory was applied in order to examine whether temporal orienting affects processes related to perceptual sensitivity or to response criterion (indexed by d' and beta measures, respectively). If temporal orienting implies perceptual preparation, we would expect to observe an increase in perceptual sensitivity (d') when a target appeared at expected, rather than unexpected, time intervals. Indeed, our behavioral results opened the possibility that focusing attention on time intervals not only enhances motor processing, as has been shown by previous research, but also might improve perceptual processing.

Modulations among the alerting, orienting and executive control networks.

This paper reports a series of experiments that were carried out in order to study the attentional system. Three networks make up this system, and each of them specializes in particular processes. The executive control network specializes in control processes, such as conflict resolution or detection of errors; the orienting network directs the processing system to the source of input and enhances its processing; the alerting network prepares the system for a fast response by maintaining an adequate level of activation in the cognitive system. Recently, Fan and collaborators [J Cogn Neurosci 14(3):340-347, 2002] designed a task to measure the efficiency of each network. We modified Fan's task to test the influences among the networks. We found that the executive control network is inhibited by the alerting network, whereas the orienting network raises the efficiency of the executive control network (Experiment 1). We also found that the alerting network influences the orienting network by speeding up its time course function (Experiment 2). Results were replicated in a third experiment, proving the effects to be stable over time, participants and experimental context, and to be potentially important as a tool for neuropsychological assessment.

Two brain pathways for attended and ignored words.

The dependency of word processing on spare attentional resources has been debated for several decades. Recent research in the study of selective attention has emphasized the role of task load in determining the fate of ignored information. In parallel to behavioral evidence, neuroimaging data show that the activation generated by unattended stimuli is eliminated in task-relevant brain regions during high attentional load tasks. We conducted an fMRI experiment to explore how word encoding proceeds in a high load situation. Participants saw a rapid series of stimuli consisting of overlapping drawings and letter strings (words or nonwords). In different blocks, task instructions directed attention to either the drawings or the letters, and subjects responded to immediate repetition of items in the attended dimension. To look at the effect of attention on word processing, we compared brain activations for words and nonwords under the two attentional conditions. As compared to nonwords, word stimuli drove responses in left frontal, left temporal and parietal areas when letters were attended. However, although the behavioral measures suggested that ignored words were not analyzed when drawings were attended, a comparison of ignored words to ignored nonwords indicated the involvement of several regions including left insula, right cerebellum and bilateral pulvinar. Interestingly, word-specific activations found when attended and ignored words were compared showed no anatomical overlap, suggesting a change in processing pathways for attended and ignored words presented in a high attentional load task.

Inattentional amnesia to words in a high attentional load task.

We investigated the dependence of visual word processes on attention by examining event-related potential (ERP) responses as subjects viewed words while their attention was engaged by a concurrent highly demanding task. We used a paradigm from a previous functional magnetic resonance imaging (fMRI) experiment [Rees, G., Russel, C., Frith, C. D., & Driver, J. Inattentional blindness vs. inattentional amnesia for fixated but ignored words. Science, 286, 2504-2506, 1999] in which participants attended either to drawings or to overlapping letters (words or nonwords) presented at a fast rate. Although previous fMRI results supported the notion that word processing was obliterated by attention withdrawal, the current electrophysiological results demonstrated that visual words are processed even under conditions in which attentional resources are engaged in a different task that does not involve reading. In two experiments, ERPs for attended words versus nonwords differed in the left frontal, left posterior, and medial scalp locations. However, in contrast to the previous fMRI results, ERPs responded differentially to ignored words and consonant strings in several regions. These results suggest that fMRI and ERPs may have differential sensitivity to some forms of neural activation. Moreover, they provide evidence to restore the notion that the brain analyzes words even when attention is tied to another dimension.

Endogenous temporal orienting of attention in detection and discrimination tasks.

Endogenous temporal-orienting effects were studied using a cuing paradigm in which the cue indicated the time interval during which the target was most likely to appear. Temporal-orienting effects were defined by lower reaction times (RTs) when there was a match between the temporal expectancy for a target (early or late) and the time interval during which the target actually appeared than when they mismatched. Temporal-orienting effects were found for both early and late expectancies with a detection task in Experiment 1. However, catch trials were decisive in whether temporal-orienting effects were observed in the early-expectancy condition. No temporal-orienting effects were found in the discrimination task. In Experiments 2A and 2B, temporal-orienting effects were observed in the discrimination task; however, they were larger when temporal expectancy was manipulated between blocks, rather than within blocks.

The three attentional networks: on their independence and interactions.

The present investigation was aimed to the study of the three attentional networks (Alerting, Orienting, and Executive Function) and their interactions. A modification of the task developed by Fan, McCandliss, Sommer, Raz, and Posner (2002) was used, in which a cost and benefit paradigm was combined with a flanker task and an alerting signal. We obtained significant interactions as predicted. The alerting network seemed to inhibit the executive function network (a larger flanker-congruency effect was found on trials where an alerting signal had been previously presented). The orienting network influenced the executive function network in a positive way (the flanker effect was smaller for cued than for uncued trials). Finally, alertness increased orienting (the cueing effect was bigger after the alerting signal). This last result, taken together with previous findings, points to an influence in the sense of a faster orienting under alertness, rather than a larger one. These results offer new insight into the functioning of the attentional system.

High density ERP indices of conscious and unconscious semantic priming.

The existence of differential brain mechanisms of conscious and unconscious processing is a matter of debate nowadays. The present experiment explores whether conscious and unconscious semantic priming in a lexical decision task at a long prime-target stimulus onset asynchrony (SOA) correlate with overlapping or different event related potential (ERP) effects. Results show that the N400 effect, which appeared when words were consciously perceived, completely disappeared when primes were masked at a level where the ability of participants to detect the prime was near chance. Instead, a rather different set of ERP effects was found to index unconscious semantic priming. This suggests that the processes at the basis of conscious and unconscious semantic analyses can under some circumstances be rather different. Moreover, our results support the notion that conscious and unconscious processes are at least partially separable in the brain.