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Ott, F.

Publications and source records attributed to Ott, F..

4 recordsLinked to original sources

Task-specific preferences guide forward planning in sequential decision-making

Everyday problems often require choosing among actions with different future consequences, even though fully evaluating those consequences is often computationally infeasible. The human brain is remarkable in its ability to solve such complex problems efficiently. In this paper, we hypothesize that this capacity arises from a principle inspired by Bayesian accounts of perception and sensorimotor control: evidence derived from effortful forward planning is integrated with task-specific preferences akin to priors, weighted by the uncertainty of these preferences. To test this hypothesis, we used a sequential decision-making task with a relatively large state space. Model comparison showed that participants' deviations from optimal forward planning are best captured by task-specific preferences, rather than by unsystematic errors, recent action-history effects, or offer-context biases. Moreover, the influence of forward planning on participants' responses depended on preference uncertainty, as evidenced by both choice behavior and reaction times, and preferences were not arbitrary but instead supported above-stochastic performance even in the absence of forward planning. Together, these results are consistent with a Bayesian-inspired interpretation of decision making, in which costly forward planning is integrated with state-dependent priors or preferences. These preferences may provide an inexpensive, quickly available first-pass solution, which is complemented by forward planning when preference-based guidance is uncertain.

neuroscience↗

scRNA-seq reveals persistent aberrant differentiation of nasal epithelium driven by TNFα and TGFβ in post-COVID syndrome

Post-COVID syndrome (PCS) currently affects approximately 3-17% of people following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and has the potential to become a significant global health burden. PCS presents with various symptoms, and methods for improved PCS assessment are presently developed to guide therapy. Nevertheless, there are few mechanistic insights and treatment options. Here, we performed single-cell RNA transcriptomics on nasal biopsies from 33 patients suffering from PCS with mild, moderate, or severe symptoms. We identified 17 different cell clusters representing 12 unique cell populations, including all major epithelial cell types of the conducting airways and basal, secretory, and ciliated cells. Severe PCS was associated with decreased numbers of ciliated cells and the presence of immune cells. Ensuing inflammatory signaling upregulated TGF{beta} and induced an epithelial-mesenchymal transition, which led to the high abundance of basal cells and a mis-stratified epithelium. We confirmed the results in vitro using an air-liquid interface culture and validated TNF as the causal inflammatory cytokine. In summary, our results show that one mechanism for sustained PCS is not through continued viral load, but through the presence of immune cells in nasal tissue leading to impaired mucosal barrier function and repeated infections. These findings could be further explored as a therapeutic option akin to other chronic inflammatory diseases by inhibiting the TNF-TGF{beta} axis, restoring the nasal epithelium, and reducing respiratory tract-related infections.

genomics↗

Forward planning driven by context-dependent conflict processing in anterior cingulate cortex

Forward planning is often essential to achieve goals over extended time periods. However, forward planning is typically computationally costly for the brain and should only be employed when necessary. The explicit calculation of how necessary forward planning will be, is in itself computationally costly. We therefore assumed that the brain generates a mapping from a particular situation to a proxy of planning value to make fast decisions about whether to use forward planning, or not. Moreover, since the state space of real world decision problems can be large, we hypothesized that such a mapping will rely on mechanisms that generalize sets of situations based on shared demand for planning. We tested this hypothesis in an fMRI study using a novel complex sequential task. Our results indicate that participants abstracted from the set of task features to more generalized control contexts that govern the balancing between forward planning and a simple response strategy. Strikingly, we found that correlations of conflict with response time and with activity in the dorsal anterior cingulate cortex were dependent on context. This context-dependency might reflect that the cognitive control system draws on category-based cognition, harnessing regularities in control demand across task space to generate control contexts that help reduce the complexity of control allocation decisions.

neuroscience↗

Dynamic integration of forward planning and heuristic preferences during multiple goal pursuit

Selecting goals and successfully pursuing them in an uncertain and dynamic environment is an important aspect of human behaviour. In order to decide which goal to pursue at what point in time, one has to evaluate the consequences of ones actions over future time steps by forward planning. However, when the goal is still temporally distant, detailed forward planning can be prohibitively costly. One way to select actions at minimal computational costs is to use heuristics. It is an open question how humans mix heuristics with forward planning to balance computational costs with goal reaching performance. To test a hypothesis about dynamic mixing of heuristics with forward planning, we used a novel stochastic sequential two-goal task. Comparing participants decisions with an optimal full planning agent, we found that at the early stages of goal-reaching sequences, in which both goals are temporally distant and planning complexity is high, on average 42% (SD = 19%) of participants choices deviated from the agents optimal choices. Only towards the end of the sequence, participants behaviour converged to near optimal performance. Subsequent model-based analyses showed that participants used heuristic preferences when the goal was temporally distant and switched to forward planning when the goal was close. Author summaryWhen we pursue our goals, there is often a moment when we recognize that we did not make the progress that we hoped for. What should we do now? Persevere to achieve the original goal, or switch to another goal? Two features of real-world goal pursuit make these decisions particularly complex. First, goals can lie far into an unpredictable future and second, there are many potential goals to pursue. When potential goals are temporally distant, human decision makers cannot use an exhaustive planning strategy, rendering simpler rules of thumb more appropriate. An important question is how humans adjust the rule of thumb approach once they get closer to the goal. We addressed this question using a novel sequential two-goal task and analysed the choice data using a computational model which arbitrates between a rule of thumb and accurate planning. We found that participants decision making progressively improved as the goal came closer and that this improvement was most likely caused by participants starting to plan ahead.

animal behavior and cognition↗