Prefrontal Computation as Active Inference

The prefrontal cortex is vital for a range of cognitive processes, including working memory, attention, and decision-making. Notably, its absence impairs the performance of tasks requiring the maintenance of information through a delay period. In this paper, we formulate a rodent task—which requires maintenance of delay-period activity—as a Markov decision process and treat optimal task performance as an (active) inference problem. We simulate the behavior of a Bayes optimal mouse presented with 1 of 2 cues that instructs the selection of concurrent visual and auditory targets on a trial-by-trial basis. Formulating inference as message passing, we reproduce features of neuronal coupling within and between prefrontal regions engaged by this task. We focus on the micro-circuitry that underwrites delay-period activity and relate it to functional specialization within the prefrontal cortex in primates. Finally, we simulate the electrophysiological correlates of inference and demonstrate the consequences of lesions to each part of our in silico prefrontal cortex. In brief, this formulation suggests that recurrent excitatory connections—which support persistent neuronal activity—encode beliefs about transition probabilities over time. We argue that attentional modulation can be understood as the contextualization of sensory input by these persistent beliefs

NICU Staff Use of Taste For Preterm Infants

Background: Food taste experience for tube fed preterm infants is sporadic and provided with milk feeds or glucose solutions. It is unknown how often taste experience is provided with tube feeding. Objectives: The research examined the knowledge, beliefs, and practices of NICU staff regarding preterm infant taste and whether these factors differ among staff by NICU site, experience, or profession. Methods: A cross sectional survey method was used and a 14 item questionnaire was developed. Results: The majority of staff lacked knowledge regarding fetal and preterm sense of taste development. Conversely, staff believed strongly in, and routinely provided taste during tube feeding. Practice varied across professions and by months of experience. Practice did not vary to the same degree by NICU sites. Conclusions: Opportunities exist to address gaps in NICU staff knowledge of preterm infant taste. Standardization of taste practices and updating of guiding documents are needed

The Thin Blue Line

23,5 cm; 353 ha

Thalamic regulation of switching between cortical representations enables cognitive flexibility

Interactions between the prefrontal cortex (PFC) and mediodorsal thalamus are critical for cognitive flexibility, yet the underlying computations are unknown. To investigate frontothalamic substrates of cognitive flexibility, we developed a behavioral task in which mice switched between different sets of learned cues that guided attention toward either visual or auditory targets. We found that PFC responses reflected both the individual cues and their meaning as task rules, indicating a hierarchical cue-to-rule transformation. Conversely, mediodorsal thalamus responses reflected the statistical regularity of cue presentation and were required for switching between such experimentally specified cueing contexts. A subset of these thalamic responses sustained context-relevant PFC representations, while another suppressed the context-irrelevant ones. Through modeling and experimental validation, we find that thalamic-mediated suppression may not only reduce PFC representational interference but could also preserve unused cortical traces for future use. Overall, our study provides a computational foundation for thalamic engagement in cognitive flexibility