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Comparative research suggests that the hypothalamus is critical in switching between survival behaviors, yet it is unclear if this is the case in humans. Here, we investigate the role of the human hypothalamus in survival switching by introducing a paradigm where volunteers switch between hunting and escape in response to encounters with a virtual predator or prey. Given the small size and low tissue contrast of the hypothalamus, we used deep learning-based segmentation to identify the individual-specific hypothalamus and its subnuclei as well as an imaging sequence optimized for hypothalamic signal acquisition. Across 2 experiments, we employed computational models with identical structures to explain internal movement generation processes associated with hunting and escaping. Despite the shared structure, the models exhibited significantly different parameter values where escaping or hunting were accurately decodable just by computing the parameters of internal movement generation processes. In experiment 2, multi-voxel pattern analyses (MVPA) showed that the hypothalamus, hippocampus, and periaqueductal gray encode switching of survival behaviors while not encoding simple motor switching outside of the survival context. Furthermore, multi-voxel connectivity analyses revealed a network including the hypothalamus as encoding survival switching and how the hypothalamus is connected to other regions in this network. Finally, model-based fMRI analyses showed that a strong hypothalamic multi-voxel pattern of switching is predictive of optimal behavioral coordination after switching, especially when this signal was synchronized with the multi-voxel pattern of switching in the amygdala. Our study is the first to identify the role of the human hypothalamus in switching between survival behaviors and action organization after switching. Studies in animal models suggest that the hypothalamus is critical for modulating the switch between survival behaviors. In this study, neuroimaging combined with computational modeling shows that the hypothalamus also modulates switching between survival actions in humans. [ABSTRACT FROM AUTHOR]

Protection often involves the capacity to prospectively plan the actions needed to mitigate harm. The computational architecture of decisions involving protection remains unclear, as well as whether these decisions differ from other beneficial prospective actions such as reward acquisition. Here we compare protection acquisition to reward acquisition and punishment avoidance to examine overlapping and distinct features across the three action types. Protection acquisition is positively valenced similar to reward. For both protection and reward, the more the actor gains, the more benefit. However, reward and protection occur in different contexts, with protection existing in aversive contexts. Punishment avoidance also occurs in aversive contexts, but differs from protection because punishment is negatively valenced and motivates avoidance. Across three independent studies (Total N = 600) we applied computational modeling to examine model-based reinforcement learning for protection, reward, and punishment in humans. Decisions motivated by acquiring protection evoked a higher degree of model-based control than acquiring reward or avoiding punishment, with no significant differences in learning rate. The context-valence asymmetry characteristic of protection increased deployment of flexible decision strategies, suggesting model-based control depends on the context in which outcomes are encountered as well as the valence of the outcome. Author summary: Acquiring protection is a ubiquitous way humans achieve safety. Humans make future-oriented decisions to acquire safety when they anticipate the possibility of future danger. These prospective safety decisions likely engage model-based control systems, which facilitate goal-oriented decision making by creating a mental map of the external environment. Inability to effectively use model-based control may reveal new insights into how safety decisions go awry in psychopathology. However, computational decision frameworks that can identify contributions of model-based control have yet to be applied to safety. Clinical science instead dominates and investigates decisions to seek out safety as a maladaptive response to threat. Focusing on maladaptive safety prevents a full understanding of how humans make decisions motivated by adaptive goals. The current studies apply computational models of decision control systems to understand how humans make adaptive decisions to acquire protection compared with acquiring reward and avoiding threat. Safety-motivated decisions elicited increased model-based control compared to reward- or threat-motivated decisions. These findings demonstrate that safety is not simply reward seeking or threat avoidance in a different form, but instead safety elicits distinct contributions of decision control systems important for goal-directed behavior. [ABSTRACT FROM AUTHOR]

University teaching, whether by professors, lecturers, or instructors, draws on a number of skills including communicating and simplifying complex ideas, to inspiring students and teaching critical thinking. Rule 9: Provide positive, kind, inclusive, and encouraging feedback The bidirectional nature of teaching is reflected in teachers posing questions that students answer, students proposing ideas that teachers critique. When feedback was accompanied by an assurance of the student's capacity to reach the teacher's high standards (e.g., statements like "I have high standards and I know you can meet them"), black students responded as positively as white students, engendering trust rather than stereotype threat. When student disagreement or criticism arises, teachers should respectfully listen, adopt currently accepted semantics, and acknowledge the limitations of outdated semantics in assigned readings or other works. [Extracted from the article]

In the natural world, stimulus-outcome associations are often ambiguous, and most associations are highly complex and situation-dependent. Learning to disambiguate these complex associations to identify which specific outcomes will occur in which situations is critical for survival. Pavlovian occasion setters are stimuli that determine whether other stimuli will result in a specific outcome. Occasion setting is a well-established phenomenon, but very little investigation has been conducted on how occasion setters are disambiguated when they themselves are ambiguous (i.e., when they do not consistently signal whether another stimulus will be reinforced). In two preregistered studies, we investigated the role of higher-order Pavlovian occasion setting in humans. We developed and tested the first computational model predicting direct associative learning, traditional occasion setting (i.e., 1st-order occasion setting), and 2nd-order occasion setting. This model operationalizes stimulus ambiguity as a mechanism to engage in higher-order Pavlovian learning. Both behavioral and computational modeling results suggest that 2nd-order occasion setting was learned, as evidenced by lack and presence of transfer of occasion setting properties when expected and the superior fit of our 2nd-order occasion setting model compared to the 1st-order occasion setting or direct associations models. These results provide a controlled investigation into highly complex associative learning and may ultimately lead to improvements in the treatment of Pavlovian-based mental health disorders (e.g., anxiety disorders, substance use). Author summary: In everyday life, we learn to associate various situations with various outcomes. For example, perhaps a specific person usually receives praise (outcome) when giving a public speech (situation), but if they give a speech after a particularly charismatic speaker (situational factor), their speech might receive less praise than usual. In our report, we conducted two experiments investigating how people learn about highly complex associations. By highly complex, we mean that whether stimulus 1 (S1) leads to outcome 1 (O1) depends on whether stimulus 2 (S2) was present or absent, and S2's effect on the S1/O1 association may further depend on whether stimulus 3 (S3) was present. Previous work has shown that S2 will modulate S1's association with O1 using two hierarchies of stimulus value, where S2 is a higher-order stimulus that affects the lower-order S1/O1 association. We hypothesized a third hierarchical value exists if S3 affects how S2 modulates the S1/OS1 association. We created formulas predicting three hierarchical levels of learning, and we tested our three-level hypothesis and formulas in two experiments, finding strong support for both. Through the experiments, we show that humans have the ability to learn highly complex associations, which suggests we may do so in everyday life. Our formulas provide insight into the computations our brains may engage in while learning. This has relevance for increasing our understanding of associative learning (which has been largely limited to a two-level hierarchy to date), as well as mental health disorders related to associative learning (e.g., anxiety, substance use). [ABSTRACT FROM AUTHOR]

Background: Cataplexy is observed in a subset of patients with narcolepsy and affects approximately 1 in 2,000 persons. Cataplexy is most often triggered by strong emotions such as laughter, which can result in transient, yet debilitating, muscle atonia. The objective of this study was to examine the neural systems underlying humor processing in individuals with cataplexy. Methodology/Principal Findings: While undergoing functional Magnetic Resonance Imaging (fMRI), we showed ten narcolepsy-cataplexy patients and ten healthy controls humorous cartoons. In addition, we examined the brain activity of one subject while in a full-blown cataplectic attack. Behavioral results showed that participants with cataplexy rated significantly fewer humorous cartoons as funny compared to controls. Concurrent fMRI showed that patients, when compared to controls and in the absence of overt cataplexy symptoms, showed pronounced activity in the emotional network including the ventral striatum and hypothalamus while viewing humorous versus non-humorous cartoons. Increased activity was also observed in the right inferior frontal gyri -a core component of the inhibitory circuitry. In comparison, the one subject who experienced a cataplectic attack showed dramatic reductions in hypothalamic activity. Conclusions: These findings suggest an overdrive of the emotional circuitry and possible compensatory suppression by cortical inhibitory regions in cataplexy. Moreover, during cataplectic attacks, the hypothalamus is characterized by a marked decrease in activity similar to that observed during sleep. One possible explanation for these findings is an initial overdrive and compensatory shutdown of the hypothalamus resulting in full cataplectic symptoms. [ABSTRACT FROM AUTHOR]

The article presents an essay which points out that biological advances in understanding human brain architecture and function may overlap in important ways with legal inquiries. The author also stresses that new studies of the criminal brain may provide moral views on responsibility and free will, which in turn will have a great impact on how legal systems punish and treat criminals.