Approach Avoidance Research Articles

Male rodent perirhinal cortex, but not ventral hippocampus, inhibition induces approach bias under object-based approach-avoidance conflict.

Neural models of approach-avoidance (AA) conflict behavior and its dysfunction have focused traditionally on the hippocampus, with the assumption that this medial temporal lobe (MTL) structure plays a ubiquitous role in arbitrating AA conflict. We challenge this perspective by using three different AA behavioral tasks in conjunction with optogenetics, to demonstrate that a neighboring region in male rats, perirhinal cortex, is also critically involved but only when conflicting motivational values are associated with objects and not contextual information. The ventral hippocampus, in contrast, was found not to be essential for object-associated AA conflict, suggesting its preferential involvement in context-associated conflict. We propose that stimulus type can impact MTL involvement during AA conflict and that a more nuanced understanding of MTL contributions to impaired AA behavior (e.g., anxiety) is required. These findings serve to expand upon the established functions of the perirhinal cortex while concurrently presenting innovative behavioral paradigms that permit the assessment of different facets of AA conflict behavior.

Social avoidance behavior modulates motivational responses to social reward-threat conflict signals: A preliminary fMRI study.

Social avoidance behavior (SAB) produces impairment in multiple domains and contributes to the development and maintenanceof several psychiatric disorders. Social behaviors such as SABare influenced by approach-avoidance (AA) motivational responses to affective facial expressions. Notably, affective facial expressions communicate varying degrees of social reward signals (happiness), social threat signals (anger), or social reward-threat conflict signals (co-occurring happiness and anger). SAB is associated with dysregulated modulation of automatic approach-avoidance (AA) motivational responses exclusively to social reward-threat conflict signals. However, no neuroimaging research has characterized SAB-related modulation of automatic and subjective AA motivational responses to social reward-threat conflict signals. We recruited 30 adults reporting clinical, moderate, or minimal SAB based on questionnaire cutoff scores. SAB groups were matched on age range and gender. During fMRI scanning, participants completed implicit and subjective approach-avoidance tasks (AATs), which involved moreincidental or moreexplicit evaluation of facial expressions that parametrically varied in social reward signals (e.g., 50%Happy), social threat signals (e.g., 50%Angry), or social reward-threat conflict signals (e.g., 50%Happy + 50%Angry). In the implicit AAT, SAB was associated with slower automatic avoidance actions and weaker amygdala-pgACC connectivity exclusively as a function of social reward-threat conflict signals. In the subjective AAT, SAB was associated with smaller increases in approach ratings, smaller decreases in avoidance ratings, and weaker dlPFC-pgACC connectivity exclusively in response to social reward-threat conflict signals. Thus, SAB is associated with dysregulated modulation of automatic and subjective AA motivational sensitivity to social reward-threat conflict signals, which may be facilitated by overlapping neural systems.

The influence of memory on approach and avoidance decisions: Investigating the role of episodic memory in social decision making

People are motivated to make social decisions to approach or avoid social targets (i.e., other people). Prior work has shown people make approach/avoidance (AA) decisions based on factors like physical appearance, race, gender, sexuality, etc., but less work has investigated the extent that memory for past encounters with social targets might influence AA decisions. Here, we investigate the role of episodic memory (memory for specific details associated with specific social targets) on AA decisions. In this investigation, participants formed positive or negative impressions based on social targets' behaviors before completing a memory test for specific episodic details associated with targets (self-generated impressions formed about target; behavior associated with targets). Participants then made AA decisions for those social targets, as well as new targets. Results showed strong approach tendencies when participants correctly remembered positive details associated with targets (impressions; behaviors) and strong avoidance tendencies when participants correctly remembered negative impressions associated with targets. For novel targets (targets not seen before and thus not associated with prior memory representations), participants showed no approach or avoidance tendencies. Overall, these findings suggest an important role for episodic memory on AA decisions, which is a potentially important mechanism in social decisions.

Perirhinal Cortex is Involved in the Resolution of Learned Approach-Avoidance Conflict Associated with Discrete Objects.

The rodent ventral and primate anterior hippocampus have been implicated in approach-avoidance (AA) conflict processing. It is unclear, however, whether this structure contributes to AA conflict detection and/or resolution, and if its involvement extends to conditions of AA conflict devoid of spatial/contextual information. To investigate this, neurologically healthy human participants first learned to approach or avoid single novel visual objects with the goal of maximizing earned points. Approaching led to point gain and loss for positive and negative objects, respectively, whereas avoidance had no impact on score. Pairs of these objects, each possessing nonconflicting (positive-positive/negative-negative) or conflicting (positive-negative) valences, were then presented during functional magnetic resonance imaging. Participants either made an AA decision to score points (Decision task), indicated whether the objects had identical or differing valences (Memory task), or followed a visual instruction to approach or avoid (Action task). Converging multivariate and univariate results revealed that within the medial temporal lobe, perirhinal cortex, rather than the anterior hippocampus, was predominantly associated with object-based AA conflict resolution. We suggest the anterior hippocampus may not contribute equally to all learned AA conflict scenarios and that stimulus information type may be a critical and overlooked determinant of the neural mechanisms underlying AA conflict behavior.

Exploring the interaction between approach-avoidance conflict and memory processing

ABSTRACTThe medial temporal lobe (MTL) has been implicated in approach-avoidance (AA) conflict processing, which arises when a stimulus is imbued with both positive and negative valences. Notably, since the MTL has been traditionally viewed as a mnemonic brain region, a pertinent question is how AA conflict and memory processing interact with each other behaviourally. We conducted two behavioural experiments to examine whether increased AA conflict processing has a significant impact on incidental mnemonic encoding and inferential reasoning. In Experiment 1, participants first completed a reward and punishment AA task and were subsequently administered a surprise recognition memory test for stimuli that were presented during high and no AA conflict trials. In Experiment 2, participants completed a reward and punishment task in which they learned the valences of objects presented in pairs (AB, BC pairs). Next, we assessed their ability to integrate information across these pairs (infer A-C relationships) and examined whether inferential reasoning was more challenging across objects with conflicting compared to non-conflicting incentive values. We observed that increased motivational conflict did not significantly impact encoding or inferential reasoning. Potential explanations for these findings are considered, including the possibility that AA conflict and memory processing are not necessarily intertwined behaviourally.

Mechanisms underlying approach-avoidance instruction effects on implicit evaluation: Results of a preregistered adversarial collaboration

Previous research demonstrated that mere instructions to approach one stimulus and avoid another stimulus result in an implicit preference for the to-be-approached over the to-be-avoided stimulus. To investigate the mechanisms underlying approach-avoidance (AA) instruction effects, we tested predictions of a propositional account and an associative self-anchoring account in a preregistered adversarial collaboration. Consistent with the propositional account, Experiment 1 showed that avoidance instructions had a negative effect on implicit evaluations over and above the positive effect of approach instructions. Consistent with the associative self-anchoring account, Experiment 2 showed that changes in implicit self-stimulus linking mediated AA instruction effects on implicit evaluations. However, mediation was only partial, in that AA instructions showed a significant effect on implicit evaluations after controlling for implicit self-stimulus linking. Together, the results support the contribution of propositional processes to AA instruction effects; the results remain ambiguous regarding an additional contribution of associative self-anchoring.

Approach-Avoidance Training Effects Are Moderated by Awareness of Stimulus-Action Contingencies.

Prior research suggests that repeatedly approaching or avoiding a stimulus changes the liking of that stimulus. In two experiments, we investigated the relationship between, on one hand, effects of approach-avoidance (AA) training on implicit and explicit evaluations of novel faces and, on the other hand, contingency awareness as indexed by participants' memory for the relation between stimulus and action. We observed stronger effects for faces that were classified as contingency aware and found no evidence that AA training caused changes in stimulus evaluations in the absence of contingency awareness. These findings challenge the standard view that AA training effects are (exclusively) the product of implicit learning processes, such as the automatic formation of associations in memory.

Early adverse experience increases emotional reactivity in juvenile rhesus macaques: relation to amygdala volume.

This study investigated the impact of infant maltreatment on juvenile rhesus monkeys' behavioral reactivity to novel stimuli and its associations with amygdala volume. Behavioral reactivity to novel stimuli of varying threat intensity was measured using Approach/Avoidance (AA) and Human Intruder (HI) tasks. In vivo magnetic resonance imaging (MRI) was used to measure amygdala volume. Interestingly, group behavioral differences were context-dependent. When exposed to a human intruder, maltreated subjects displayed more anxious behaviors than controls; however, when presented with fear-evoking objects, maltreated animals exhibited increased aggression and a shorter latency to inspect the objects. Finally, under testing conditions with the lowest levels of threat (neutral novel objects) maltreated animals also showed shorter latencies to inspect objects, and reduced avoidance and increased exploration compared to controls. This suggests alterations in threat assessment and less behavioral inhibition in animals with early adverse experience compared to controls. Some of these behavioral responses were associated with amygdala volume, which was positively correlated with abuse rates received during infancy, particularly reflecting a relationship with exploration, consistent with previous studies.