Effects of blocked versus interleaved training on relative value learning.

In reinforcement learning tasks, people learn the values of options relative to other options in the local context. Prior research suggests that relative value learning is enhanced when choice contexts are temporally clustered in a blocked sequence compared to a randomly interleaved sequence. The present study was aimed at further investigating the effects of blocked versus interleaved training using a choice task that distinguishes among different contextual encoding models.

Testing models of context-dependent outcome encoding in reinforcement learning.

Previous studies of reinforcement learning (RL) have established that choice outcomes are encoded in a context-dependent fashion. Several computational models have been proposed to explain context-dependent encoding, including reference point centering and range adaptation models. The former assumes that outcomes are centered around a running estimate of the average reward in each choice context, while the latter assumes that outcomes are compared to the minimum reward and then scaled by an estimate of the range of outcomes in each choice context.

Reinforcement learning in and out of context: The effects of attentional focus.

In reinforcement learning (RL) tasks, decision makers learn the values of actions in a context-dependent fashion. Although context dependence has many advantages, it can lead to suboptimal preferences when choice options are extrapolated beyond their original encoding contexts. Here, we tested whether we could manipulate context dependence in RL by introducing a secondary task designed to bias attention toward either absolute or relative outcomes.

Context effects on choice under cognitive load.

The context-dependent nature of choice is well illustrated by decoy effects, in which adding an alternative to a choice set can change the preference relations among the other alternatives. The current within-subjects study tested whether manipulating cognitive load affects the magnitude of attraction and compromise decoy effects. Participants (n = 96) made simulated online grocery shopping choices from three options described by price and quality for each grocery item they encountered.

Evaluating non-affective cross-modal congruence effects on emotion perception.

Although numerous studies have shown that people are more likely to integrate consistent visual and auditory signals, the role of non-affective congruence in emotion perception is unclear. This registered report examined the influence of non-affective cross-modal congruence on emotion perception. In Experiment 1, non-affective congruence was manipulated by matching or mismatching gender between visual and auditory modalities.

Evoked and induced power oscillations linked to audiovisual integration of affect.

Our affective experiences are influenced by combined multisensory information. Although the enhanced effects of congruent audiovisual information on our affective experiences have been well documented, the role of neural oscillations in the audiovisual integration of affective signals remains unclear. First, it is unclear whether oscillatory activity changes as a function of valence.

Crossmodal negativity bias in semantic processing.

Negative events have greater influence on cognitive processing compared with positive events, a phenomenon referred to as the negativity bias. Previous studies have shown that reaction times (RTs) to negatively valenced items are slower in semantic tasks. According to the automatic vigilance hypothesis, these effects are caused by preferential attention to negative stimuli or features diverting cognitive resources away from semantic processing.

Autonomic responses to choice outcomes: Links to task performance and reinforcement-learning parameters.

Previous work has shown that autonomic responses to choice feedback can predict subsequent decision-making. In this study, we tested whether skin conductance responses (SCRs) and heart rate (HR) decelerations following the presentation of choice outcomes predict Iowa Gambling Task performance in nonclinical participants (n = 64). We also examined how these signals related to parameters of a reinforcement-learning (RL) model.

A study in affect: Predicting valence from fMRI data.

Previous studies have shown that affective valence states induced by brief stimulus presentations are identifiable from whole brain activation patterns observed with functional magnetic resonance imaging (fMRI). However, it is unclear whether those results will generalize to identification of continuous changes in affective valence states under naturalistic settings, such as watching a movie. We examined neural representations of signed (positive versus negative) and unsigned (valenced versus non-valenced) valence on previously collected fMRI data from 17 participants who watched a TV show episode in a passive viewing task in the scanner (Chen et al.

An fMRI Study of Affective Congruence across Visual and Auditory Modalities.

Evaluating multisensory emotional content is a part of normal day-to-day interactions. We used fMRI to examine brain areas sensitive to congruence of audiovisual valence and their overlap with areas sensitive to valence. Twenty-one participants watched audiovisual clips with either congruent or incongruent valence across visual and auditory modalities.

Correction to: Context effects on reproduced magnitudes from short-term and long-term memory.

The citation of Hellström (1985) in the body and the reference section of this article is incorrectly printed as Helström.

Context effects on reproduced magnitudes from short-term and long-term memory.

Extant research has demonstrated strong contextual dependencies in reproducing magnitudes of perceptual stimuli from short-term memory. Two experiments examined how context as defined by (a) the mean of the distribution, (b) stimulus ranks, (c) values of anchor stimuli used in the reproduction task, and (d) values from the most recent trial operate on estimates of square size. Experiment 1 demonstrated distributional contrast effects on ratings of squares and distributional assimilation effects on reproduction of squares from short-term memory for the same participants.

Context effects in reproduction and perception of song tempo.

Studies of tempo perception suggest that exposure to a distribution of predominantly faster or slower versions of a song can shift one's memory for the original tempo toward the contextual tempos. Three experiments were conducted to examine whether similar assimilation effects would occur when participants are asked to reproduce the tempo of a song from memory. In Experiments 1 and 2, participants listened to a tempo-altered version of a pop song prior to tapping out the original tempo from memory on each trial.

Distinguishing abstract from concrete concepts in supramodal brain regions.

Concrete words have been shown to have a processing advantage over abstract words, yet theoretical accounts and neural correlates underlying the distinction between concrete and abstract concepts are still unresolved. In an fMRI study, participants performed a property verification task on abstract and concrete concepts. Property comparisons of concrete concepts were predominantly based on either visual or haptic features.

Temporal dynamics of audiovisual affective processing.

This study used event-related potentials (ERPs) to investigate the time course of auditory, visual, and audiovisual affective processing. Stimuli consisted of naturalistic silent videos, instrumental music clips, or combination of the two, with valence varied at three levels for each modality and arousal matched across valence conditions. Affective ratings of the unimodal and multimodal stimuli showed evidence of visual dominance, congruency, and negativity dominance effects.

Identification of task sets within and across stimulus modalities.

Previous studies have shown that task sets can be identified from functional magnetic resonance imaging (fMRI) data. However, these results may be partially confounded by differences in stimulus features associated with the different tasks. We disentangle stimulus modality and task features by presenting the same stimulus while varying task, and conversely, presenting different stimuli using the same task.

Modelling audiovisual integration of affect from videos and music.

Two experiments examined how affective values from visual and auditory modalities are integrated. Experiment 1 paired music and videos drawn from three levels of valence while holding arousal constant. Experiment 2 included a parallel combination of three levels of arousal while holding valence constant.

Representations of modality-general valence for videos and music derived from fMRI data.

This study tested for neural representations of valence that are shared across visual and auditory modalities referred to as modality-general representations. On a given trial participants made either affective or semantic judgments of short silent videos or music samples. For each modality valence was manipulated at three levels, positive, neutral, and negative, while controlling for the level of arousal.

Identifying Core Affect in Individuals from fMRI Responses to Dynamic Naturalistic Audiovisual Stimuli.

Recent research has demonstrated that affective states elicited by viewing pictures varying in valence and arousal are identifiable from whole brain activation patterns observed with functional magnetic resonance imaging (fMRI). Identification of affective states from more naturalistic stimuli has clinical relevance, but the feasibility of identifying these states on an individual trial basis from fMRI data elicited by dynamic multimodal stimuli is unclear. The goal of this study was to determine whether affective states can be similarly identified when participants view dynamic naturalistic audiovisual stimuli.

Comparison of physiological responses to affect eliciting pictures and music.

Recent investigations of the neural correlates of affect elicited from different modalities have found both modality-general and modality-specific representations (Chikazoe et al., 2014). The implications for how physiological responses to affect differ across stimulus modalities have not been fully investigated.

Testing the absolute-tempo hypothesis: context effects for familiar and unfamiliar songs.

In two experiments, we investigated context effects on tempo judgments for familiar and unfamiliar songs performed by popular artists. In Experiment 1, participants made comparative tempo judgments to a remembered standard for song clips drawn from either a slow or a fast context, created by manipulating the tempos of the same songs. Although both familiar and unfamiliar songs showed significant shifts in their points of subjective equality toward the tempo context values, more-familiar songs showed significantly reduced contextual bias.

Representations of modality-specific affective processing for visual and auditory stimuli derived from functional magnetic resonance imaging data.

There is converging evidence that people rapidly and automatically encode affective dimensions of objects, events, and environments that they encounter in the normal course of their daily routines. An important research question is whether affective representations differ with sensory modality. This research examined the nature of the dependency of affect and sensory modality at a whole-brain level of analysis in an incidental affective processing paradigm.

Asymmetry of the endogenous opioid system in the human anterior cingulate: a putative molecular basis for lateralization of emotions and pain.

Lateralization of the processing of positive and negative emotions and pain suggests an asymmetric distribution of the neurotransmitter systems regulating these functions between the left and right brain hemispheres. By virtue of their ability to selectively mediate euphoria, dysphoria, and pain, the μ-, δ-, and κ-opioid receptors and their endogenous ligands may subserve these lateralized functions. We addressed this hypothesis by comparing the levels of the opioid receptors and peptides in the left and right anterior cingulate cortex (ACC), a key area for emotion and pain processing.

Examining similarity structure: multidimensional scaling and related approaches in neuroimaging.

This paper covers similarity analyses, a subset of multivariate pattern analysis techniques that are based on similarity spaces defined by multivariate patterns. These techniques offer several advantages and complement other methods for brain data analyses, as they allow for comparison of representational structure across individuals, brain regions, and data acquisition methods. Particular attention is paid to multidimensional scaling and related approaches that yield spatial representations or provide methods for characterizing individual differences.

From maps to navigation: the role of cues in finding locations in a virtual environment.

In two experiments, participants navigated through a large arena within a virtual environment (VE) to a location encoded in memory from a map. In both experiments, participants recalled locations by navigating through the VE, but in Experiment 2, they additionally recalled the locations on the original map. Two cues were located outside and above the walls of the arena at either north-south locations or east-west locations.