Fear

Ralph Adolphs explains how the brain creates emotions including fear, joy, and awe, and discusses evidence-based approaches to emotion regulation. The episode connects neural mechanisms with attention, decision-making, and bodily state.

Background: This study explores how threat learning contributes to the development of fear and anxiety. We aim to determine if observed responses indicate a general novelty marker, are solely linked to arousal, and are influenced by valence. Adopting the transdiagnostic RDoC approach, this study focuses on acute and sustained threat within negative valence systems.Aims: Utilizing a modified Threat Conditioning and Extinction Task (TCET), we examined fear memory traces in healthy over three phases (preconditioning, conditioning, extinction). The study involved subjective ratings of faces associ

An animal’s behavioral state is reflected in the dynamics of population activity and its capacity to process sensory information. Previous studies in mammalian brains have demonstrated a relationship between behavioral states and information processing (Lee et al., 2016, 2019, 2020). However, these studies have been limited to exploring how population dynamics and sensory representation changes in specific cortical areas. Thanks to its transparency at early life stage and the advent of selective plane illumination microscopy, the zebrafish brain is an attractive model that allow for whole brai

Defensive brain states, such as fear and anxiety, evolved as mediators of multidimensional reactions to threat, which encompass integrated autonomic, behavioral and endocrine responses. Multiple interconnected brain structures have been involved in defensive reactions, in particular the midbrain’s periaqueductal gray (PAG), the amygdala, and different cortical areas such as the auditory and prefrontal cortices, together processing information at multiple levels of the neuraxis. Several roles pertaining to higher-order threat processing have been assigned to the medial prefrontal cortex (mPFC),

To survive in a dangerous world, animals must overcome intense fear during traumatic experiences and ultimately learn which actions to take in the future to avoid threats (active avoidance). Unlike instinctive responses, active avoidance demands deliberate decision-making, action, and an understanding of the behavioral consequences involved. The nucleus accumbens (NAc) is an important node for goal directed behavior, serving as an interface between motivation and action by integrating information from cortical and subcortical afferents through a diversity of interneuron and projection cell typ

Constant monitoring of behavioral patterns shapes successful social interactions. Factors such as interpersonal distance and emotional expressions prompt specific responses to facilitate functional social exchanges. Despite extensive research on these topics, studying how these features influence human physiological responses in an ecological yet controlled environment has often proven challenging. Moreover, the relation between a possible dysregulation of these physiological reactions and social anxiety remains unclear. Using a 3D virtual setting, we found increased physiological responses (

…mechanisms regulating emotions such as fear and anxiety are crucial. The basolateral amygdala (BLA) is a key structure involved in the regulation of those emotional processes. Within the BLA, excitatory principal neurons are responsible for the encoding and relay of emotionally relevant information to other brain structures while GABAergic interneurons, despite being a minority, tightly regulate their activity. Among the key interneuron classes, parvalbumin-expressing (PV) interneurons have been shown to be in

Fear is essential to an individual's survival. Abnormal fear will make people or animals more vulnerable to danger, and even lead to a series of neuropsychiatric diseases. Previous studies have suggested that functional abnormalities of the ventral tegmental area (VTA) may lead to fear-related neuropsychiatric diseases, such as post-traumatic stress disorder and schizophrenia, but the underlying mechanisms remain unclear. Our preliminary data has first shown that the projection from the central amygdala (CeA) to the ventral tegmental area could regulate fear. However, the specific cell types a

In emotion research, anxiety and fear have always been interconnected, sharing overlapping brain structures and neural circuitry. Recent investigations, however, have unveiled parallel long-range projection pathways originating from the ventral hippocampus, shedding light on their distinct roles in anxiety and fear. Specifically, vCA1 projections to the lateral hypothalamus and medial prefrontal cortex are associated with anxiety-related experiences, whereas vCA1 projections to the amygdala mediate context-dependent fear. However, the precise mechanisms coordinating these parallel vCA1 project

…As such, fear, one of our basic emotions, must be kept in a functional balance to minimize risk-taking while allowing for the pursuit of essential needs. However, the neural mechanisms underlying this adaptive modulation of fear remain poorly understood. In

Coping with threatening situations requires both identifying stimuli predicting danger and selecting adaptive behavioral responses in order to survive. The dorso medial prefrontal cortex (dmPFC) is a critical structure involved in the regulation of threat-related behaviour, yet it is still largely unclear how threat-predicting stimuli and defensive behaviours are associated within prefrontal networks in order to successfully drive adaptive responses. To address these questions, we used a combination of extracellular recordings, neuronal decoding approaches, and optogenetic manipulations to sho

…or flee in danger, we often feel fear. Tracing the deep history of danger gives a different perspective. The first cells living billions of years ago had to detect and respond to danger in order to survive. Life is about not being dead, and behavior is a major way that organisms hold death off. Although behavior does not require a nervous system, complex organisms have brain circuits for detecting and responding to danger, the deep roots of which go back to the first cells. But these circuits do not make fear, and fear is no

…debate on the meaning of the term fear. Whereas some have argued that fear (as well as other emotions) relies on cognitive capacities that are unique to humans, others view it as a negative state constructed from essential building blocks. This latter definition posits that fear states are associated with varying readouts that one could consider to be parallel processes or serial events tied to a specific hierarchy. Within this framework, innate defensive behaviors are considered to be common displays of fear states that l

Empathy plays a critical role in social interactions, and many species, including rodents, display evolutionarily conserved behavioral antecedents of empathy. In both humans and rodents, the anterior cingulate cortex (ACC) encodes information about the affective state of others. However, little is known about which downstream targets of the ACC contribute to empathy behaviors. We optimized a protocol for the social transfer of pain behavior in mice and compared the ACC-dependent neural circuitry responsible for this behavior with the neural circuitry required for the social transfer of two rel