Threat of punishment motivates memory encoding via amygdala, not midbrain, interactions with the medial temporal lobe

The effects of auditory consequences on visuomotor adaptation and motor memory

Sensorimotor adaptation is a form of motor learning that is essential for maintaining motor performance across the lifespan and is integral to recovery of function after neurological injury. Recent research indicates that experiencing a balance-threatening physical consequence when making a movement error during adaptation can enhance subsequent motor memory. This is perhaps not surprising, as learning to avoid injury is critical for our survival and well-being. Reward and punishment can also differentially modify aspects of motor learning. However, it remains unclear whether other forms of non-physical consequences can impact motor learning. Here we tested the hypothesis that a loud acoustic stimulus linked to a movement error during adaptation could lead to greater generalization and consolidation. Two groups of participants (n = 12 each) adapted to a new, prism-induced visuomotor mapping while performing a precision walking task. One group experienced an unexpected loud acoustic stimulus (85 dB tone) when making foot-placement errors during adaptation. This auditory consequence group adapted faster and showed greater generalization with an interlimb transfer task, but not greater generalization to an obstacle avoidance task. Both groups showed faster relearning (i.e., savings) during the second testing session one week later despite the presence of an interference block of trials following initial adaptation, indicating successful consolidation. However, we did not find significant differences between groups with relearning during session 2. Overall, our results suggest that auditory consequences may serve as a useful method to improve motor learning, though further research is required.

Conscious expectancy rather than associative strength elicits brain activity during single-cue fear conditioning

The neurocognitive processes underlying Pavlovian conditioning in humans are still largely debated. The conventional view is that conditioned responses (CRs) emerge automatically as a function of the contingencies between a conditioned stimulus (CS) and an unconditioned stimulus (US). As such, the associative strength model asserts that the frequency or amplitude of CRs reflects the strength of the CS-US associations. Alternatively, the expectation model asserts that the presentation of the CS triggers conscious expectancy of the US, which is responsible for the production of CRs. The present study tested the hypothesis that there are dissociable brain networks related to the expectancy and associative strength theories using a single-cue fear conditioning paradigm with a pseudo-random intermittent reinforcement schedule during functional magnetic resonance imaging. Participants' (n = 21) trial-by-trial expectations of receiving shock displayed a significant linear effect consistent with the expectation model. We also found a positive linear relationship between the expectancy model and activity in frontoparietal brain areas including the dorsolateral prefrontal cortex (PFC) and dorsomedial PFC. While an exploratory analysis found a linear relationship consistent with the associated strength model in the insula and early visual cortex, our primary results are consistent with the view that conscious expectancy contributes to CRs.

Instructed motivational states bias reinforcement learning and memory formation

Motivation influences goals, decisions, and memory formation. Imperative motivation links urgent goals to actions, narrowing the focus of attention and memory. Conversely, interrogative motivation integrates goals over time and space, supporting rich memory encoding for flexible future use. We manipulated motivational states via cover stories for a reinforcement learning task: The imperative group imagined executing a museum heist, whereas the interrogative group imagined planning a future heist. Participants repeatedly chose among four doors, representing different museum rooms, to sample trial-unique paintings with variable rewards (later converted to bonus payments). The next day, participants performed a surprise memory test. Crucially, only the cover stories differed between the imperative and interrogative groups; the reinforcement learning task was identical, and all participants had the same expectations about how and when bonus payments would be awarded. In an initial sample and a preregistered replication, we demonstrated that imperative motivation increased exploitation during reinforcement learning. Conversely, interrogative motivation increased directed (but not random) exploration, despite the cost to participants' earnings. At test, the interrogative group was more accurate at recognizing paintings and recalling associated values. In the interrogative group, higher value paintings were more likely to be remembered; imperative motivation disrupted this effect of reward modulating memory. Overall, we demonstrate that a prelearning motivational manipulation can bias learning and memory, bearing implications for education, behavior change, clinical interventions, and communication.

Trial-by-trial fluctuations in amygdala activity track motivational enhancement of desirable sensory evidence during perceptual decision-making

People are biased toward seeing outcomes that they are motivated to see. For example, wanting their favored team to prevail biases sports fans to perceive an ambiguous foul in a manner that is favorable to the team they support. Here, we test the hypothesis that such motivational biases in perceptual decision-making are associated with amygdala activity. We used monetary incentives to experimentally manipulate participants to want to see one percept over another while they performed a categorization task involving ambiguous images. Participants were more likely to categorize an image as the category we motivated them to see, suggesting that wanting to see a particular percept biased their perceptual decisions. Heightened amygdala activity was associated with motivation consistent categorizations and tracked trial-by-trial enhancement of neural activity in sensory cortices encoding the desirable category. Analyses using a drift diffusion model further suggest that trial-by-trial amygdala activity was specifically associated with biases in the accumulation of sensory evidence. In contrast, frontoparietal regions commonly associated with biases in perceptual decision-making were not associated with motivational bias. Altogether, our results suggest that wanting to see an outcome biases perceptual decisions via distinct mechanisms and may depend on dynamic fluctuations in amygdala activity.

Tag and capture: how salient experiences target and rescue nearby events in memory

The long-term fate of a memory is not exclusively determined by the events occurring at the moment of encoding. Research at the cellular, circuit, and behavioral levels is beginning to reveal how neurochemical activations in the moments surrounding an event can retroactively and proactively rescue weak memory for seemingly mundane experiences. We review emerging evidence showing enhancement of weakly formed memories encoded minutes to hours before or after a related motivationally relevant experience. We discuss proposed neurobiological mechanisms for strengthening weak memories formed in temporal proximity to a strong event, and how this knowledge could be leveraged to improve memory for information that is prone to forgetting.

Functional activation of insula and dorsal anterior cingulate for conflict control against larger monetary loss in young adults with subthreshold depression: a preliminary study

Subthreshold depression (StD) is associated with higher risk of later developing major depressive disorder (MDD). Deficits of goal-directed behaviors regarding the motional, motivational, and conflict control are found in MDD. The current study examined neural underpinning of conflict control against monetary punishment in StD compared to MDD and healthy controls (HC). Seventy-one participants (HC, n = 27; StD, n = 21; MDD, n = 23) in their mid-20's completed self-reports. Preprocessing of functional magnetic resonance imaging acquired for the Simon task against larger or smaller monetary punishment was conducted using ENIGMA HALFpipe version 1.2.1. Neural correlates of conflict control against monetary punishment that could vary with either diagnosis or PHQ-9 total score were examined using a general linear model of FSL. Simon effect was effective for reaction time and accuracy in every subgroup of diagnosis and regardless of the size of monetary punishment. Conflict control against larger monetary loss was associated with higher functional activation of left insula in StD than HC and MDD. StD showed lower functional activation of left dorsal anterior cingulate (dACC) than MDD for conflict control against larger monetary loss. For conflict control against smaller monetary loss, StD demonstrated higher functional activation of left paracentral lobule and right putamen compared to HC. Directed acyclic graphs showed directional associations from suicidal ideation, sadness, and concentration difficulty to functional activation of paracentral lobule, ventromedial prefrontal cortex (vmPFC), and thalamus for conflict control against monetary loss. Differential functional activation of insula and dACC for conflict control against larger monetary loss could be a brain phenotype of StD. Item-level depressive symptoms of suicidal ideation, sadness, and concentration difficulty could be reflected in the conflict control-related functional activation of paracentral lobule (against smaller monetary loss), vmPFC and thalamus (against larger monetary loss), respectively.

A Systematic Approach to Neuropsychiatric Intervention: Functional Neuroanatomy Underlying Symptom Domains as Targets for Treatment

An ever-growing population experiences a wide range of psychopathologies, and there is now more than ever a need for clear differential diagnoses between disorders. Furthering this need is the fact that many psychological, psychiatric, and neurological disorders have overlapping features. Functional neuroimaging has been shown to differentiate not only between the function of different brain structures but also between the roles of these structures in functional networks. The aim of this article is to aid in the goal of parsing out disorders on the basis of specific symptom domains by utilizing the most recent literature on functional networks. Current literature on the role of brain networks in relation to different psychopathological symptom domains is examined and corresponding circuit-based therapies that have been or may be used to treat them are discussed. Research on depression, obsession and compulsions, addiction, anxiety, and psychosis is reviewed. An understanding of networks and their specific dysfunctions opens the possibility of a new form of psychopathological treatment.

Effective connectivity underlying reward-based executive control

Motivational influences on cognitive control play an important role in shaping human behavior. Cognitive facilitation through motivators such as prospective reward or punishment is thought to depend on regions from the dopaminergic mesocortical network, primarily the ventral tegmental area (VTA), inferior frontal junction (IFJ), and anterior cingulate cortex (ACC). However, how interactions between these regions relate to motivated control remains elusive. In the present functional magnetic resonance imaging study, we used dynamic causal modeling (DCM) to investigate effective connectivity between left IFJ, ACC, and VTA in a task-switching paradigm comprising three distinct motivational conditions (prospective monetary reward or punishment and a control condition). We found that while prospective punishment significantly facilitated switching between tasks on a behavioral level, interactions between IFJ, ACC, and VTA were characterized by modulations through prospective reward but not punishment. Our DCM results show that IFJ and VTA modulate ACC activity in parallel rather than by interaction to serve task demands in reward-based cognitive control. Our findings further demonstrate that prospective reward and punishment differentially affect neural control mechanisms to initiate decision-making.

Memory consolidation as an adaptive process

We rely on our long-term memories to guide future behaviors, making it adaptive to prioritize the retention of goal-relevant, salient information in memory. In this review, we discuss findings from rodent and human research to demonstrate that active processes during post-encoding consolidation support the selective stabilization of recent experience into adaptive, long-term memories. Building upon literatures focused on dynamics at the cellular level, we highlight that consolidation also transforms memories at the systems level to support future goal-relevant behavior, resulting in more generalized memory traces in the brain and behavior. We synthesize previous literatures spanning animal research, human cognitive neuroscience, and cognitive psychology to propose an integrative framework for adaptive consolidation by which goal-relevant memoranda are "tagged" for subsequent consolidation, resulting in selective transformations to the structure of memories that support flexible, goal-relevant behaviors.

A multinomial modelling approach to face identity recognition during instructed threat

To organise future behaviour, it is important to remember both the central and contextual aspects of a situation. We examined the impact of contextual threat or safety, learned through verbal instructions, on face identity recognition. In two studies (N = 140), 72 face-context compounds were presented each once within an encoding session, and an unexpected item/source recognition task was performed afterwards (including 24 new faces). Hierarchical multinomial processing tree modelling served to estimate individual parameters of item (face identity) and source memory (threat or safety context) as well as guessing behaviour. Results show that language was highly effective in establishing threatening and safe context conditions. In Study 1, a fleeting picture stream (1 s per picture) led to poor item and source recognition. Prolonged presentation times (Study 2 with 6 s per picture) improved face memory but no contextual modulation was observed. Thus, incidental face learning was surprisingly poor and rapidly changing contextual settings might have interfered with the accurate encoding of face identity information and item-source binding.

Punishment-modulated attentional capture is context specific

Attention prioritizes stimuli previously associated with punishment. Despite the importance of this process for survival and adaptation, the potential generalization of punishment-related attentional biases has been largely ignored in the literature. This study aimed to determine whether stimulus-punishment associations learned in a specific context bias attention in another context (in which the stimulus was never paired with punishment). We examined this issue using an antisaccade task in which participants had to shift their gaze in the opposite direction of a colored square during stimulus-outcome learning. Two contexts and three colors were employed. One color was associated with punishment (i.e., electrical shock) in one context and never paired with punishment in the other context. For a second color, the punishment-context relationship was reversed. A third color never paired with shock in either context (neutral) was included in Experiment 1 but absent in Experiment 2. Participants then performed search for a shape-defined target in an extinction phase (in which no shock was delivered) in which attentional bias for the colors was assessed. Context was manipulated via the background image upon which the stimuli were presented. In each of the two experiments, a bias to selectively orient toward the color that had been associated with punishment in the current context was observed, suggesting that punishment-modulated attentional priority is context specific.

Memory of my victory and your defeat: Contributions of reward- and memory-related regions to the encoding of winning events in competitions with others

Social interactions enhance human memories, but little is known about how the neural mechanisms underlying episodic memories are modulated by rewarding outcomes in social interactions. To investigate this, fMRI data were recorded while healthy young adults encoded unfamiliar faces in either a competition or a control task. In the competition task, participants encoded opponents' faces in the rock-paper-scissors game, where trial-by-trial outcomes of Win, Draw, and Lose for participants were shown by facial expressions of opponents (Angry, Neutral, and Happy). In the control task, participants encoded faces by assessing facial expressions. After encoding, participants recognized faces previously learned. Behavioral data showed that emotional valence for opponents' Angry faces as the Win outcome was rated positively in the competition task, whereas the rating for Angry faces was rated negatively in the control task, and that Angry faces were remembered more accurately than Neutral or Happy faces in both tasks. fMRI data showed that activation in the medial orbitofrontal cortex (mOFC) paralleled the pattern of valence ratings, with greater activation for the Win than Draw or Lose conditions of the competition task, and the Angry condition of the control task. Moreover, functional connectivity between the mOFC and hippocampus was increased in Win compared to Angry, and the mOFC-hippocampus functional connectivity predicted individual differences in subsequent memory performance only in Win of the competition task, but not in any other conditions of the two tasks. These results demonstrate that the memory enhancement by context-dependent social rewards involves interactions between reward- and memory-related regions.

The effect of concurrent reward on aversive information processing in the brain

Neural networks for the processing of appetitive and aversive information, in isolation, have been well characterized. However, how the brain integrates competing signals associated with simultaneous appetitive and aversive information is less clear. In particular, it is unknown how the presence of concurrent reward modulates the processing of an aversive event throughout the brain. Here, we utilized a four-armed bandit task in an fMRI study to measure the representation of an aversive electric shock with and without the simultaneous receipt of monetary reward. Using a region of interest (ROI) approach, we first identified regions activated by the experience of aversive electric shock, and then measured how this shock-related activation is modulated by concurrent reward using independent data. Informed by prior literature and our own preliminary data, analyses focused on the dorsolateral prefrontal cortex, anterior and posterior insula, anterior cingulate cortex, and the thalamus and somatosensory cortex. We hypothesized that the neural response to punishment in these ROIs would be attenuated by the presence of concurrent reward. However, we found no evidence of concurrent reward attenuating the neural response to punishment in any ROI and also no evidence of concurrent punishment attenuating the neural response to reward in exploratory analyses. Altogether, our findings are consistent with the idea that neural networks responsible for the processing of reward and punishment signals are largely independent of one another, and that representations of overall value or utility are arrived at through the integration of separate reward and punishment signals at later stages of information processing.

The influence of threat and aversive motivation on conflict processing in the Stroop task

Motivated attention can be driven by the desire to maximize gains or escape punishment. In the Stroop task, when rewards can be obtained by responding quickly to certain colors, corresponding color words are prioritized and produce enhanced interference, suggesting transfer of an attentional bias from color hues to color words. In the present study, we replicated this transfer effect using reward and conducted a parallel experiment exchanging the prospect of reward (appetitive motivation) with the opportunity to avert punishment (aversive motivation). Participants were required to identify the color (hue) of color words and received electric shocks for responses to particular hues that were slow or incorrect. Shock-related words similarly impaired color-ink naming performance. In contrast to prior studies with reward, however, responding to hues associated with shock was also impaired, with threat producing an increase in error rate that ironically resulted in more frequent shocks. Our results suggest that aversive and appetitive motivation affect attention to task-relevant information differently, although each produces a common bias in automatic stimulus processing presumably driven by valence.

Motivated suppression of value- and threat-modulated attentional capture

Attention prioritizes stimuli previously associated with reward or punishment. The present study examined whether this attentional bias, widely considered to be involuntary and automatic, could be suppressed with sufficient motivation. Participants performed visual search for a shape-defined target. One color-singleton distractor predicted the possibility of receiving a reward and another an electric shock, with each outcome occurring infrequently. Participants were informed that the likelihood to earn a reward or avert punishment depended on fast and accurate performance, thus providing strong motivation to resist distraction by reward- and shock-related stimuli. Results revealed a reduction in the magnitude of attentional capture by reward- and threat-associated distractors, relative to neutral distractors, that persisted into extinction. In a second experiment, we replicated the suppression of value-modulated attentional capture in the absence of the shock condition, thus confirming that the suppression did not result from the presence of threat. Finally, in a third experiment, we replicated the typical pattern of attentional capture by reward cues using a more conventional procedure in which the motivation to suppress valent stimuli was low (the likelihood to be rewarded was high and not contingent on fast performance). This study demonstrates that signals for reward and threat can be actively suppressed with sufficient motivation. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Amygdala and ventral tegmental area differentially interact with hippocampus and cortical medial temporal lobe during rest in humans

Neuromodulatory regions that detect salience, such as amygdala and ventral tegmental area (VTA), have distinct effects on memory. Yet, questions remain about how these modulatory regions target subregions across the hippocampus and medial temporal lobe (MTL) cortex. Here, we sought to characterize how VTA and amygdala subregions (i.e., basolateral amygdala and central-medial amygdala) interact with hippocampus head, body, and tail, as well as cortical MTL areas of perirhinal cortex and parahippocampal cortex in a task-free state. To quantify these interactions, we used high-resolution resting state fMRI and characterized pair-wise, partial correlations across regions-of-interest. We found that basolateral amygdala showed greater functional coupling with hippocampus head, hippocampus tail, and perirhinal cortex when compared to either VTA or central-medial amygdala. Furthermore, the VTA showed greater functional coupling with hippocampus tail when compared to central-medial amygdala. There were no significant differences in functional coupling with hippocampus body and parahippocampal cortex. These results support a framework by which neuromodulatory regions do not indiscriminately influence all MTL subregions equally, but rather bias information processing to discrete MTL targets. These findings provide a more specified model of the intrinsic properties of systems underlying MTL neuromodulation. This emphasizes the need to consider heterogeneity both across and within neuromodulatory systems to better understand affective memory.

Differential modulation of cognitive control networks by monetary reward and punishment

Incentives are primary determinants of if and how well an organism will perform a given behavior. Here, we examined how incentive valence and magnitude influence task switching, a critical cognitive control process, and test the predictions that the anterior cingulate cortex (ACC) and the ventral striatum (vStr) function as key nodes linking motivation and control systems in the brain. Our results indicate that reward and punishment incentives have both common and distinct effects on cognitive control at the behavioral and neurobiological levels. For example, reward incentives led to greater activity in the ACC during the engagement of control relative to punishments. Furthermore, the neural responses to reward and punishment differed as a function of individual sensitivity to each incentive valence. Functional connectivity analyses suggest a role for vStr in signaling motivational value during cognitive control and as a potential link between motivation and control networks. Overall, our findings suggest that similar changes in observed behavior (e.g. response accuracy) under reward and punishment incentives are mediated by, at least partially, distinct neurobiological substrates.

Differential motor learning via reward and punishment

Visuomotor adaptation involves multiple processes such as explicit learning, implicit learning from sensory prediction errors, and model-free mechanisms like use-dependent plasticity. Recent findings show that reward and punishment differently affect visuomotor adaptation. This study examined whether punishment and reward had distinct effects on explicit learning. When participants practised adapting to a large, abrupt visual rotation during reaching for a virtual visual target, visual feedback of the cursor was not provided. Only performance-based scalar reward or punishment feedback (money gained or lost) was used, thereby emphasising explicit processes during adaptation. The results revealed that punishment, compared with reward, induced faster adaptation and greater variability of reaching in the initial phase of adaptation. We interpret these findings as reflecting enhanced explicit learning, likely due to loss aversion.

Measuring attention to reward as an individual trait: the value-driven attention questionnaire (VDAQ)

Reward history is a powerful determinant of what we pay attention to. This influence of reward on attention varies substantially across individuals, being related to a variety of personality variables and clinical conditions. Currently, the ability to measure and quantify attention-to-reward is restricted to the use of psychophysical laboratory tasks, which limits research into the construct in a variety of ways. In the present study, we introduce a questionnaire designed to provide a brief and accessible means of assessing attention-to-reward. Scores on the questionnaire correlate with other measures known to be related to attention-to-reward and predict performance on multiple laboratory tasks measuring the construct. In demonstrating this relationship, we also provide evidence that attention-to-reward as measured in the lab, an automatic and implicit bias in information processing, is related to overt behaviors and motivations in everyday life as assessed via the questionnaire. Variation in scores on the questionnaire is additionally associated with a distinct biomarker in brain connectivity, and the questionnaire exhibits acceptable test-retest reliability. Overall, the Value-Driven Attention Questionnaire (VDAQ) provides a useful proxy-measure of attention-to-reward that is much more accessible than typical laboratory assessments.

Emotional enhancement of memory for neutral information: The complex interplay between arousal, attention, and anticipation

It can be challenging to explain why certain mundane details circumstantial to an emotional event are nonetheless remembered long after the experience. Here, we examined how attention selectively shapes memory for neutral objects that happen to coincide with either an unexpected or anticipated emotional event. Pictures of neutral objects were presented for 2 s and terminated with either a high-intensity shock, a low-intensity shock, or no shock. Recognition memory was tested 24 -hs later in a surprise test. Results showed no effect of shock intensity on memory for attended objects when shocks were unpredictable (Experiment 1). Similarly, there was no effect of shock intensity for attended objects when shock delivery was signaled before the object appeared (Experiment 2). There was a reduction in memory for unattended objects paired with an anticipated high-intensity shock (Experiment 3). Finally, subjects recognized slightly more attended objects paired with a high-intensity shock if shock intensity was signaled one second after the object was encoded (Experiment 4). We conclude that simply pairing objects with high-intensity shocks is insufficient to drive episodic memory enhancements for neutral information. But anticipation of an impending source of arousal can induce bidirectional effects: attending to an impending emotional event interferes with encoding of neutral information, but encoding an object just prior to anticipation of an emotional event can sometimes benefit memory. Overall, these results highlight a complex interplay between arousal, attention, and anticipation on emotion-induced memory for neutral information.

Differential impact of reward and punishment on functional connectivity after skill learning

Reward and punishment shape behavior, but the mechanisms underlying their effect on skill learning are not well understood. Here, we tested whether the functional connectivity of premotor cortex (PMC), a region known to be critical for learning of sequencing skills, is altered after training when reward or punishment is given during training. Resting-state fMRI was collected in two experiments before and after participants trained on either a serial reaction time task (SRTT; n = 36) or force-tracking task (FTT; n = 36) with reward, punishment, or control feedback. In each experiment, training-related change in PMC functional connectivity was compared across feedback groups. In both tasks, we found that reward and punishment differentially affected PMC functional connectivity. On the SRTT, participants trained with reward showed an increase in functional connectivity between PMC and cerebellum as well as PMC and striatum, while participants trained with punishment showed an increase in functional connectivity between PMC and medial temporal lobe connectivity. After training on the FTT, subjects trained with control and reward showed increases in PMC connectivity with parietal and temporal cortices after training, while subjects trained with punishment showed increased PMC connectivity with ventral striatum. While the results from the two experiments overlapped in some areas, including ventral pallidum, temporal lobe, and cerebellum, these regions showed diverging patterns of results across the two tasks for the different feedback conditions. These findings suggest that reward and punishment strongly influence spontaneous brain activity after training, and that the regions implicated depend on the task learned.

Threat reduces value-driven but not salience-driven attentional capture

What we direct our attention to is strongly influenced by both bottom-up and top-down processes. Moreover, the control of attention is biased by prior learning, such that attention is automatically captured by stimuli previously associated with either reward or threat. It is unknown whether value-oriented and threat-oriented mechanisms of selective information processing function independently of one another, or whether they interact with each other in the selection process. Here, we introduced the threat of electric shock into the value-driven attentional capture paradigm to examine whether the experience of threat influences the attention capturing quality of previously reward-associated stimuli. The results showed that value-driven attentional capture was blunted by the experience of threat. This contrasts with previous reports of threat potentiating attentional capture by physically salient stimuli, which we replicate here. Our findings demonstrate that threat selectively interferes with value-based but not salience-based attentional priority, consistent with a competitive relationship between value-based and threat-based information processing. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Punishment-related memory-guided attention: Neural dynamics of perceptual modulation

Remembering the outcomes of past experiences allows us to generate future expectations and shape selection in the long-term. A growing number of studies has shown that learned positive reward values impact spatial memory-based attentional biases on perception. However, whether memory-driven attentional biases extend to punishment-related values has received comparatively less attention. Here, we manipulated whether recent spatial contextual memories became associated with successful avoidance of punishment (potential monetary loss). Behavioral and electrophysiological measures were collected from 27 participants during a subsequent memory-based attention task, in which we tested for the effect of punishment avoidance associations. Punishment avoidance significantly amplified effects of spatial contextual memories on visual search processes within natural scenes. Compared to non-associated scenes, contextual memories paired with punishment avoidance lead to faster responses to targets presented at remembered locations. Event-related potentials elicited by target stimuli revealed that acquired motivational value of specific spatial locations, by virtue of their association with past avoidance of punishment, dynamically affected neural signatures of early visual processing (indexed by larger P1 and earlier N1 potentials) and target selection (as indicated by reduced N2pc potentials). The present results extend our understanding of how memory, attention, and punishment-related mechanisms interact to optimize perceptual decision in real world environments.

Retroactive and graded prioritization of memory by reward

Many decisions are based on an internal model of the world. Yet, how such a model is constructed from experience and represented in memory remains unknown. We test the hypothesis that reward shapes memory for sequences of events by retroactively prioritizing memory for objects as a function of their distance from reward. Human participants encountered neutral objects while exploring a series of mazes for reward. Across six data sets, we find that reward systematically modulates memory for neutral objects, retroactively prioritizing memory for objects closest to the reward. This effect of reward on memory emerges only after a 24-hour delay and is stronger for mazes followed by a longer rest interval, suggesting a role for post-reward replay and overnight consolidation, as predicted by neurobiological data in animals. These findings demonstrate that reward retroactively prioritizes memory along a sequential gradient, consistent with the role of memory in supporting adaptive decision-making.

I lie, why don't you: Neural mechanisms of individual differences in self-serving lying

People tend to lie in varying degrees. To advance our understanding of the underlying neural mechanisms of this heterogeneity, we investigated individual differences in self-serving lying. We performed a functional magnetic resonance imaging study in 37 participants and introduced a color-reporting game where lying about the color would in general lead to higher monetary payoffs but would also be punished if get caught. At the behavioral level, individuals lied to different extents. Besides, individuals who are more dishonest showed shorter lying response time, whereas no significant correlation was found between truth-telling response time and the degree of dishonesty. At the neural level, the left caudate, ventromedial prefrontal cortex (vmPFC), right inferior frontal gyrus (IFG), and left dorsolateral prefrontal cortex (dlPFC) were key regions reflecting individual differences in making dishonest decisions. The dishonesty associated activity in these regions decreased with increased dishonesty. Subsequent generalized psychophysiological interaction analyses showed that individual differences in self-serving lying were associated with the functional connectivity among the caudate, vmPFC, IFG, and dlPFC. More importantly, regardless of the decision types, the neural patterns of the left caudate and vmPFC during the decision-making phase could be used to predict individual degrees of dishonesty. The present study demonstrated that lying decisions differ substantially from person to person in the functional connectivity and neural activation patterns which can be used to predict individual degrees of dishonesty.

Acute stress throughout the memory cycle: Diverging effects on associative and item memory

Acute stress can modulate memory for individual parts of an event (items), but whether it similarly influences memory for associations between items remains unclear. We used a within-subjects design to explore the influence of acute stress on item and associative memory in humans. Participants associated negative words with neutral objects, rated their subjective arousal for each pair, and completed delayed item and paired associative recognition tasks. We found strikingly different patterns of acute stress effects on item and associative memory: for high-arousal pairs, preencoding stress enhanced associative memory, whereas postencoding stress enhanced item memory. Preretrieval stress consistently impaired both forms of memory. We found that the influence of stress-induced cortisol also varied, with a linear relationship between cortisol and item memory but a quadratic relationship between cortisol and associative memory. These findings reveal key differences in how stress, throughout the memory cycle, shapes our memories for items and associations. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Context and Time Matter: Effects of Emotion and Motivation on Episodic Memory Overtime

Previous studies have shown that compared with neutral cues, stimuli with positive and negative/stressful contexts or reward and punishment cues are remembered better. However, it is unclear whether the enhanced effect differs in emotion or motivation dimensions and the passage of time. We addressed these issues by manipulating different contextual cues for neutral words at different time intervals. In experiment 1, subjects were asked to learn words with picture contexts in positive, negative/stressful, and neutral valences and were tested by old/new word recognition and contextual judgment 10 min, 1 day, and 1 week later. In experiment 2, the reward and punishment motivations were manipulated by monetary cues during learning. Word recognition and contextual judgment were assessed 10 min, 1 day, 1 week, and 1 month after the study. Compared with negative and punishment conditions, the words in positive and reward contexts were recognized better at shorter intervals, which was associated with recollection process. In contrast, the words in negative and punishment contexts were recognized better at longer intervals, which was mainly associated with familiarity process. These results clarified how different dimensions of emotional and motivational contexts influence memory at short and long intervals and highlighted the role of contextual features in memory formation and consolidation.

Motivational valence alters memory formation without altering exploration of a real-life spatial environment

Volitional exploration and learning are key to adaptive behavior, yet their characterization remains a complex problem for cognitive science. Exploration has been posited as a mechanism by which motivation promotes memory, but this relationship is not well-understood, in part because novel stimuli that motivate exploration also reliably elicit changes in neuromodulatory brain systems that directly alter memory formation, via effects on neural plasticity. To deconfound interrelationships between motivation, exploration, and memory formation we manipulated motivational state prior to entering a spatial context, measured exploratory responses to the context and novel stimuli within it, and then examined motivation and exploration as predictors of memory outcomes. To elicit spontaneous exploration, we used the physical space of an art exhibit with affectively rich content; we expected motivated exploration and memory to reflect multiple factors, including not only motivational valence, but also individual differences. Motivation was manipulated via an introductory statement framing exhibit themes in terms of Promotion- or Prevention-oriented goals. Participants explored the exhibit while being tracked by video. They returned 24 hours later for recall and spatial memory tests, followed by measures of motivation, personality, and relevant attitude variables. Promotion and Prevention condition participants did not differ in terms of group-level exploration time or memory metrics, suggesting similar motivation to explore under both framing contexts. However, exploratory behavior and memory outcomes were significantly more closely related under Promotion than Prevention, indicating that Prevention framing disrupted expected depth-of-encoding effects. Additionally, while trait measures predicted exploration similarly across framing conditions, traits interacted with motivational framing context and facial affect to predict memory outcomes. This novel characterization of motivated learning implies that dissociable behavioral and biological mechanisms, here varying as a function of valence, contribute to memory outcomes in complex, real-life environments.

Locus Coeruleus Activity Strengthens Prioritized Memories Under Arousal

Recent models posit that bursts of locus ceruleus (LC) activity amplify neural gain such that limited attention and encoding resources focus even more on prioritized mental representations under arousal. Here, we tested this hypothesis in human males and females using fMRI, neuromelanin MRI, and pupil dilation, a biomarker of arousal and LC activity. During scanning, participants performed a monetary incentive encoding task in which threat of punishment motivated them to prioritize encoding of scene images over superimposed objects. Threat of punishment elicited arousal and selectively enhanced memory for goal-relevant scenes. Furthermore, trial-level pupil dilations predicted better scene memory under threat, but were not related to object memory outcomes. fMRI analyses revealed that greater threat-evoked pupil dilations were positively associated with greater scene encoding activity in LC and parahippocampal cortex, a region specialized to process scene information. Across participants, this pattern of LC engagement for goal-relevant encoding was correlated with neuromelanin signal intensity, providing the first evidence that LC structure relates to its activation pattern during cognitive processing. Threat also reduced dynamic functional connectivity between high-priority (parahippocampal place area) and lower-priority (lateral occipital cortex) category-selective visual cortex in ways that predicted increased memory selectivity. Together, these findings support the idea that, under arousal, LC activity selectively strengthens prioritized memory representations by modulating local and functional network-level patterns of information processing.SIGNIFICANCE STATEMENT Adaptive behavior relies on the ability to select and store important information amid distraction. Prioritizing encoding of task-relevant inputs is especially critical in threatening or arousing situations, when forming these memories is essential for avoiding danger in the future. However, little is known about the arousal mechanisms that support such memory selectivity. Using fMRI, neuromelanin MRI, and pupil measures, we demonstrate that locus ceruleus (LC) activity amplifies neural gain such that limited encoding resources focus even more on prioritized mental representations under arousal. For the first time, we also show that LC structure relates to its involvement in threat-related encoding processes. These results shed new light on the brain mechanisms by which we process important information when it is most needed.

Human aging reduces the neurobehavioral influence of motivation on episodic memory

The neural circuitry mediating the influence of motivation on long-term declarative or episodic memory formation is delineated in young adults, but its status is unknown in healthy aging. We examined the effect of reward and punishment anticipation on intentional declarative memory formation for words using an event-related functional magnetic resonance imaging (fMRI) monetary incentive encoding task in twenty-one younger and nineteen older adults. At 24-hour memory retrieval testing, younger adults were significantly more likely to remember words associated with motivational cues than neutral cues. Motivational enhancement of memory in younger adults occurred only for recollection ("remember" responses) and not for familiarity ("familiar" responses). Older adults had overall diminished memory and did not show memory gains in association with motivational cues. Memory encoding associated with monetary rewards or punishments activated motivational (substantia nigra/ventral tegmental area) and memory-related (hippocampus) brain regions in younger, but not older, adults during the target word periods. In contrast, older and younger adults showed similar activation of these brain regions during the anticipatory motivational cue interval. In a separate monetary incentive delay task that did not require learning, we found evidence for relatively preserved striatal reward anticipation in older adults. This supports a potential dissociation between incidental and intentional motivational processes in healthy aging. The finding that motivation to obtain rewards and avoid punishments had reduced behavioral and neural influence on intentional episodic memory formation in older compared to younger adults is relevant to life-span theories of cognitive aging including the dopaminergic vulnerability hypothesis.

Adaptive scaling of reward in episodic memory: a replication study

Reward is thought to enhance episodic memory formation via dopaminergic consolidation. Bunzeck, Dayan, Dolan, and Duzel [(2010). A common mechanism for adaptive scaling of reward and novelty. Human Brain Mapping, 31, 1380–1394] provided functional magnetic resonance imaging (fMRI) and behavioural evidence that reward and episodic memory systems are sensitive to the contextual value of a reward—whether it is relatively higher or lower—as opposed to absolute value or prediction error. We carried out a direct replication of their behavioural study and did not replicate their finding that memory performance associated with reward follows this pattern of adaptive scaling. An effect of reward outcome was in the opposite direction to that in the original study, with lower reward outcomes leading to better memory than higher outcomes. There was a marginal effect of reward context, suggesting that expected value affected memory performance. We discuss the robustness of the reward memory relationship to variations in reward context, and whether other reward-related factors have a more reliable influence on episodic memory.

Motivated Cognition: Effects of Reward, Emotion, and Other Motivational Factors Across a Variety of Cognitive Domains

A growing body of literature has demonstrated that motivation influences cognitive processing. The breadth of these effects is extensive and span influences of reward, emotion, and other motivational processes across all cognitive domains. As examples, this scope includes studies of emotional memory, value-based attentional capture, emotion effects on semantic processing, reward-related biases in decision making, and the role of approach/avoidance motivation on cognitive scope. Additionally, other less common forms of motivation–cognition interactions, such as self-referential and motoric processing can also be considered instances of motivated cognition. Here I outline some of the evidence indicating the generality and pervasiveness of these motivation influences on cognition, and introduce the associated ‘research nexus’ at Collabra: Psychology.

Memory Performance for Everyday Motivational and Neutral Objects Is Dissociable from Attention

Episodic memory is typically better for items coupled with monetary reward or punishment during encoding. It is yet unclear whether memory is also enhanced for everyday objects with appetitive or aversive values learned through a lifetime of experience, and to what extent episodic memory enhancement for motivational and neutral items is attributable to attention. In a first experiment, we investigated attention to everyday motivational objects using eye-tracking during free-viewing and subsequently tested episodic memory using a remember/know procedure. Attention was directed more to aversive stimuli, as evidenced by longer viewing durations, whereas recollection was higher for both appetitive and aversive objects. In the second experiment, we manipulated the visual contrast of neutral objects through changes of contrast to further dissociate attention and memory encoding. While objects presented with high visual contrast were looked at longer, recollection was best for objects presented in unmodified, medium contrast. Generalized logistic mixed models on recollection performance showed that attention as measured by eye movements did not enhance subsequent memory, while motivational value (Experiment 1) and visual contrast (Experiment 2) had quadratic effects in opposite directions. Our findings suggest that an enhancement of incidental memory encoding for appetitive items can occur without an increase in attention and, vice versa, that enhanced attention towards salient neutral objects is not necessarily associated with memory improvement. Together, our results provide evidence for a double dissociation of attention and memory effects under certain conditions.

Distinct medial temporal networks encode surprise during motivation by reward versus punishment

Adaptive motivated behavior requires predictive internal representations of the environment, and surprising events are indications for encoding new representations of the environment. The medial temporal lobe memory system, including the hippocampus and surrounding cortex, encodes surprising events and is influenced by motivational state. Because behavior reflects the goals of an individual, we investigated whether motivational valence (i.e., pursuing rewards versus avoiding punishments) also impacts neural and mnemonic encoding of surprising events. During functional magnetic resonance imaging (fMRI), participants encountered perceptually unexpected events either during the pursuit of rewards or avoidance of punishments. Despite similar levels of motivation across groups, reward and punishment facilitated the processing of surprising events in different medial temporal lobe regions. Whereas during reward motivation, perceptual surprises enhanced activation in the hippocampus, during punishment motivation surprises instead enhanced activation in parahippocampal cortex. Further, we found that reward motivation facilitated hippocampal coupling with ventromedial PFC, whereas punishment motivation facilitated parahippocampal cortical coupling with orbitofrontal cortex. Behaviorally, post-scan testing revealed that reward, but not punishment, motivation resulted in greater memory selectivity for surprising events encountered during goal pursuit. Together these findings demonstrate that neuromodulatory systems engaged by anticipation of reward and punishment target separate components of the medial temporal lobe, modulating medial temporal lobe sensitivity and connectivity. Thus, reward and punishment motivation yield distinct neural contexts for learning, with distinct consequences for how surprises are incorporated into predictive mnemonic models of the environment.

The simple act of choosing influences declarative memory

Individuals value the opportunity to make choices and exert control over their environment. This perceived sense of agency has been shown to have broad influences on cognition, including preference, decision-making, and valuation. However, it is unclear whether perceived control influences memory. Using a combined behavioral and functional magnetic resonance imaging approach, we investigated whether imbuing individuals with a sense of agency over their learning experience influences novel memory encoding. Participants encoded objects during a task that manipulated the opportunity to choose. Critically, unlike previous work on active learning, there was no relationship between individuals' choices and the content of memoranda. Despite this, we found that the opportunity to choose resulted in robust, reliable enhancements in declarative memory. Neuroimaging results revealed that anticipatory activation of the striatum, a region associated with decision-making, valuation, and exploration, correlated with choice-induced memory enhancements in behavior. These memory enhancements were further associated with interactions between the striatum and hippocampus. Specifically, anticipatory signals in the striatum when participants are alerted to the fact that they will have to choose one of two memoranda were associated with encoding success effects in the hippocampus on a trial-by-trial basis. The precedence of the striatal signal in these interactions suggests a modulatory relationship of the striatum over the hippocampus. These findings not only demonstrate enhanced declarative memory when individuals have perceived control over their learning but also support a novel mechanism by which these enhancements emerge. Furthermore, they demonstrate a novel context in which mesolimbic and declarative memory systems interact.

Neural correlates of object-associated choice behavior in the perirhinal cortex of rats

The perirhinal cortex (PRC) is reportedly important for object recognition memory, with supporting physiological evidence obtained largely from primate studies. Whether neurons in the rodent PRC also exhibit similar physiological correlates of object recognition, however, remains to be determined. We recorded single units from the PRC in a PRC-dependent, object-cued spatial choice task in which, when cued by an object image, the rat chose the associated spatial target from two identical discs appearing on a touchscreen monitor. The firing rates of PRC neurons were significantly modulated by critical events in the task, such as object sampling and choice response. Neuronal firing in the PRC was correlated primarily with the conjunctive relationships between an object and its associated choice response, although some neurons also responded to the choice response alone. However, we rarely observed a PRC neuron that represented a specific object exclusively regardless of spatial response in rats, although the neurons were influenced by the perceptual ambiguity of the object at the population level. Some PRC neurons fired maximally after a choice response, and this post-choice feedback signal significantly enhanced the neuronal specificity for the choice response in the subsequent trial. Our findings suggest that neurons in the rat PRC may not participate exclusively in object recognition memory but that their activity may be more dynamically modulated in conjunction with other variables, such as choice response and its outcomes.

Value-based modulation of memory encoding involves strategic engagement of fronto-temporal semantic processing regions

A number of prior fMRI studies have focused on the ways in which the midbrain dopaminergic reward system coactivates with hippocampus to potentiate memory for valuable items. However, another means by which people could selectively remember more valuable to-be-remembered items is to be selective in their use of effective but effortful encoding strategies. To broadly examine the neural mechanisms of value on subsequent memory, we used fMRI to assess how differences in brain activity at encoding as a function of value relate to subsequent free recall for words. Each word was preceded by an arbitrarily assigned point value, and participants went through multiple study-test cycles with feedback on their point total at the end of each list, allowing for sculpting of cognitive strategies. We examined the correlation between value-related modulation of brain activity and participants' selectivity index, which measures how close participants were to their optimal point total, given the number of items recalled. Greater selectivity scores were associated with greater differences in the activation of semantic processing regions, including left inferior frontal gyrus and left posterior lateral temporal cortex, during the encoding of high-value words relative to low-value words. Although we also observed value-related modulation within midbrain and ventral striatal reward regions, our fronto-temporal findings suggest that strategic engagement of deep semantic processing may be an important mechanism for selectively encoding valuable items.

Mechanisms of motivation-cognition interaction: challenges and opportunities

Recent years have seen a rejuvenation of interest in studies of motivation-cognition interactions arising from many different areas of psychology and neuroscience. The present issue of Cognitive, Affective, & Behavioral Neuroscience provides a sampling of some of the latest research from a number of these different areas. In this introductory article, we provide an overview of the current state of the field, in terms of key research developments and candidate neural mechanisms receiving focused investigation as potential sources of motivation-cognition interaction. However, our primary goal is conceptual: to highlight the distinct perspectives taken by different research areas, in terms of how motivation is defined, the relevant dimensions and dissociations that are emphasized, and the theoretical questions being targeted. Together, these distinctions present both challenges and opportunities for efforts aiming toward a more unified and cross-disciplinary approach. We identify a set of pressing research questions calling for this sort of cross-disciplinary approach, with the explicit goal of encouraging integrative and collaborative investigations directed toward them.

Motivation and cognitive control: from behavior to neural mechanism

Research on cognitive control and executive function has long recognized the relevance of motivational factors. Recently, however, the topic has come increasingly to center stage, with a surge of new studies examining the interface of motivation and cognitive control. In the present article we survey research situated at this interface, considering work from cognitive and social psychology and behavioral economics, but with a particular focus on neuroscience research. We organize existing findings into three core areas, considering them in the light of currently vying theoretical perspectives. Based on the accumulated evidence, we advocate for a view of control function that treats it as a domain of reward-based decision making. More broadly, we argue that neuroscientific evidence plays a critical role in understanding the mechanisms by which motivation and cognitive control interact. Opportunities for further cross-fertilization between behavioral and neuroscientific research are highlighted.

Locus coeruleus neuromodulation of memories encoded during negative or unexpected action outcomes

When people experience surprising or sub-optimal performance outcomes, an increase in autonomic arousal helps allocate cognitive resources to adjust behavior accordingly. The locus-coeruleus-norepinephrine (LC-NE) system regulates a central orienting response to behaviorally relevant events, and might therefore signal the need to attend to and learn from performance feedback. Memories of such events also rely on elevated NE, suggesting that LC activity not only responds to salient performance outcomes but also strengthens memory for stimuli associated with their occurrence. In the present study, we used a monetary incentive delay paradigm to determine whether LC functional connectivity during reaction time feedback relates to trial-by-trial memory of preceding photo-objects. We used one psychophysiological interaction (PPI) analysis to examine patterns of LC functional connectivity that were associated with subsequent memory for picture trials in which negative or positive feedback was given, and a second PPI analysis to investigate whether successfully encoded objects from trials with uncertain outcomes were related to distinct patterns of LC functional connectivity across the brain. The PPI results revealed that successfully encoded negative feedback trials (i.e., responses exceeding the response deadline) were uniquely associated with enhanced functional coupling between the LC and left anterior insula. Furthermore, successful memory for objects in low reaction time certainty trials (i.e., responses closest to the response deadline) were linked to positive LC functional coupling with left dorsolateral prefrontal cortex. These findings suggest that noradrenergic influences help facilitate memory encoding during outcome processing via dynamic interactions with regions that process negative or unexpected feedback.

Pain anticipation recruits the mesolimbic system and differentially modulates subsequent recognition memory

The ability to encode information into long-term memory is not a passive process but can be influenced by motivational factors. While the mesolimbic system has long been associated with reward-driven memory enhancement, the precise neurobiology of processing aversive events and their effects on declarative learning remain unclear. To address this issue, human subjects encoded a series of scene images, which was combined with cues predicting an aversive electric shock with different probabilities (0.2, 0.5, 0.8). Subsequently, recognition memory for the scenes was tested using a remember/know procedure. In a behavioral experiment, shock probability had linear effects on familiarity and inverted u-shaped effects on recollection. While the behavioral effect was absent in experiment 2 (fMRI), at the neural level encoding-related activity in the hippocampus mimicked the recollection specific quadratic effect, whereas activity in the anterior parahippocampal gyrus mirrored the familiarity specific linear relationship that was evident in experiment 1. Importantly, the probability of upcoming shocks was linearly coded in the substantia nigra / ventral tegmental area, and pain associated brain regions, such as the insula, responded to shock delivery. Our results demonstrate that anticipating primary aversive events recruits the human mesolimbic system and differentially modulates declarative memory functions via medial temporal lobe structures.

Encoding and reinstatement of threat: recognition potentials

On a recognition test, stimuli originally encoded in the context of shock threat show an enhanced late parietal positivity during later recognition compared to stimuli encoded during safety, particularly for emotionally arousing stimuli. The present study investigated whether this ERP old/new effect is further influenced when a threat context is reinstated during the recognition test. ERPs were measured in a yes-no recognition test for words rated high or low in emotional arousal that were encoded and recognized in the context of cues that signaled threat of shock or safety. Correct recognition of words encoded under threat, irrespective of reinstatement, was associated with an enhanced old-new ERP difference (500-700ms; centro-parietal), and this difference was only reliable for emotionally arousing words. Taken together, the data suggest that information processed in a stressful context are associated with better recollection on later recognition, an effect that was not modulated by reinstating the stressful context at retrieval.

Positive and negative reinforcement activate human auditory cortex

Prior studies suggest that reward modulates neural activity in sensory cortices, but less is known about punishment. We used functional magnetic resonance imaging and an auditory discrimination task, where participants had to judge the duration of frequency modulated tones. In one session correct performance resulted in financial gains at the end of the trial, in a second session incorrect performance resulted in financial loss. Incorrect performance in the rewarded as well as correct performance in the punishment condition resulted in a neutral outcome. The size of gains and losses was either low or high (10 or 50 Euro cent) depending on the direction of frequency modulation. We analyzed neural activity at the end of the trial, during reinforcement, and found increased neural activity in auditory cortex when gaining a financial reward as compared to gaining no reward and when avoiding financial loss as compared to receiving a financial loss. This was independent on the size of gains and losses. A similar pattern of neural activity for both gaining a reward and avoiding a loss was also seen in right middle temporal gyrus, bilateral insula and pre-supplemental motor area, here however neural activity was lower after correct responses compared to incorrect responses. To summarize, this study shows that the activation of sensory cortices, as previously shown for gaining a reward is also seen during avoiding a loss.

Reprint of: DAT genotype modulates striatal processing and long-term memory for items associated with reward and punishment

Previous studies have shown that appetitive motivation enhances episodic memory formation via a network including the substantia nigra/ventral tegmental area (SN/VTA), striatum and hippocampus. This functional magnetic resonance imaging (fMRI) study now contrasted the impact of aversive and appetitive motivation on episodic long-term memory. Cue pictures predicted monetary reward or punishment in alternating experimental blocks. One day later, episodic memory for the cue pictures was tested. We also investigated how the neural processing of appetitive and aversive motivation and episodic memory were modulated by dopaminergic mechanisms. To that end, participants were selected on the basis of their genotype for a variable number of tandem repeat polymorphism of the dopamine transporter (DAT) gene. The resulting groups were carefully matched for the 5-HTTLPR polymorphism of the serotonin transporter gene. Recognition memory for cues from both motivational categories was enhanced in participants homozygous for the 10-repeat allele of the DAT, the functional effects of which are not known yet, but not in heterozygous subjects. In comparison with heterozygous participants, 10-repeat homozygous participants also showed increased striatal activity for anticipation of motivational outcomes compared to neutral outcomes. In a subsequent memory analysis, encoding activity in striatum and hippocampus was found to be higher for later recognized items in 10-repeat homozygotes compared to 9/10-repeat heterozygotes. These findings suggest that processing of appetitive and aversive motivation in the human striatum involve the dopaminergic system and that dopamine plays a role in memory for both types of motivational information. In accordance with animal studies, these data support the idea that encoding of motivational events depends on dopaminergic processes in the hippocampus.

DAT genotype modulates striatal processing and long-term memory for items associated with reward and punishment

Previous studies have shown that appetitive motivation enhances episodic memory formation via a network including the substantia nigra/ventral tegmental area (SN/VTA), striatum and hippocampus. This functional magnetic resonance imaging (fMRI) study now contrasted the impact of aversive and appetitive motivation on episodic long-term memory. Cue pictures predicted monetary reward or punishment in alternating experimental blocks. One day later, episodic memory for the cue pictures was tested. We also investigated how the neural processing of appetitive and aversive motivation and episodic memory were modulated by dopaminergic mechanisms. To that end, participants were selected on the basis of their genotype for a variable number of tandem repeat polymorphism of the dopamine transporter (DAT) gene. The resulting groups were carefully matched for the 5-HTTLPR polymorphism of the serotonin transporter gene. Recognition memory for cues from both motivational categories was enhanced in participants homozygous for the 10-repeat allele of the DAT, the functional effects of which are not known yet, but not in heterozygous subjects. In comparison with heterozygous participants, 10-repeat homozygous participants also showed increased striatal activity for anticipation of motivational outcomes compared to neutral outcomes. In a subsequent memory analysis, encoding activity in striatum and hippocampus was found to be higher for later recognized items in 10-repeat homozygotes compared to 9/10-repeat heterozygotes. These findings suggest that processing of appetitive and aversive motivation in the human striatum involve the dopaminergic system and that dopamine plays a role in memory for both types of motivational information. In accordance with animal studies, these data support the idea that encoding of motivational events depends on dopaminergic processes in the hippocampus.

Underconnectivity between voice-selective cortex and reward circuitry in children with autism

Individuals with autism spectrum disorders (ASDs) often show insensitivity to the human voice, a deficit that is thought to play a key role in communication deficits in this population. The social motivation theory of ASD predicts that impaired function of reward and emotional systems impedes children with ASD from actively engaging with speech. Here we explore this theory by investigating distributed brain systems underlying human voice perception in children with ASD. Using resting-state functional MRI data acquired from 20 children with ASD and 19 age- and intelligence quotient-matched typically developing children, we examined intrinsic functional connectivity of voice-selective bilateral posterior superior temporal sulcus (pSTS). Children with ASD showed a striking pattern of underconnectivity between left-hemisphere pSTS and distributed nodes of the dopaminergic reward pathway, including bilateral ventral tegmental areas and nucleus accumbens, left-hemisphere insula, orbitofrontal cortex, and ventromedial prefrontal cortex. Children with ASD also showed underconnectivity between right-hemisphere pSTS, a region known for processing speech prosody, and the orbitofrontal cortex and amygdala, brain regions critical for emotion-related associative learning. The degree of underconnectivity between voice-selective cortex and reward pathways predicted symptom severity for communication deficits in children with ASD. Our results suggest that weak connectivity of voice-selective cortex and brain structures involved in reward and emotion may impair the ability of children with ASD to experience speech as a pleasurable stimulus, thereby impacting language and social skill development in this population. Our study provides support for the social motivation theory of ASD.

Temporal characteristics of the influence of punishment on perceptual decision making in the human brain

Perceptual decision making is the process by which information from sensory systems is combined and used to influence our behavior. In addition to the sensory input, this process can be affected by other factors, such as reward and punishment for correct and incorrect responses. To investigate the temporal dynamics of how monetary punishment influences perceptual decision making in humans, we collected electroencephalography (EEG) data during a perceptual categorization task whereby the punishment level for incorrect responses was parametrically manipulated across blocks of trials. Behaviorally, we observed improved accuracy for high relative to low punishment levels. Using multivariate linear discriminant analysis of the EEG, we identified multiple punishment-induced discriminating components with spatially distinct scalp topographies. Compared with components related to sensory evidence, components discriminating punishment levels appeared later in the trial, suggesting that punishment affects primarily late postsensory, decision-related processing. Crucially, the amplitude of these punishment components across participants was predictive of the size of the behavioral improvements induced by punishment. Finally, trial-by-trial changes in prestimulus oscillatory activity in the alpha and gamma bands were good predictors of the amplitude of these components. We discuss these findings in the context of increased motivation/attention, resulting from increases in punishment, which in turn yields improved decision-related processing.