How to build a cognitive map.

Learning and interpreting the structure of the environment is an innate feature of biological systems, and is integral to guiding flexible behaviors for evolutionary viability. The concept of a cognitive map has emerged as one of the leading metaphors for these capacities, and unraveling the learning and neural representation of such a map has become a central focus of neuroscience. In recent years, many models have been developed to explain cellular responses in the hippocampus and other brain areas. Because it can be difficult to see how these models differ, how they relate and what each model can contribute, this Review aims to organize these models into a clear ontology. This ontology reveals parallels between existing empirical results, and implies new approaches to understand hippocampal-cortical interactions and beyond.

Reinforcement Learning: Full Glass or Empty - Depends Who You Ask.

An extension of the prediction error theory of dopamine, imported from artificial intelligence, represents the full distribution over future rewards rather than only the average and better explains dopamine responses.

DIAGNOSTIC USE OF CRITTENDEN'S ATTACHMENT MEASURES IN FAMILY COURT IS NOT BEYOND A REASONABLE DOUBT.

We express serious doubt and cautioning regarding Spieker and Crittenden's (2010) claim that attachment measures associated with the dynamic-maturational model of attachment and adaptation (DMM; Crittenden, 2016) can be used for court decision-making. We demonstrate, using Crittenden's and coworkers' (e.g., Spieker & Crittenden, 2010) own data, that such measures have (a) insufficient reliability for use in individual diagnosis and (b) cannot retrodict maltreatment with sufficient sensitivity or specificity for court use. Just as atypical forms of attachment are sometimes observed among children reared adequately, typical (secure or mildly insecure) forms of attachment are sometimes observed among maltreated children and among children of caregivers struggling with psychopathology or socioeconomic adversity. The stakes are high, so it is imperative that court decisions accord with the rule of law. Certainty beyond a reasonable doubt is required, and DMM measures do not meet that requirement.

Pausing controls branching between productive and non-productive pathways during initial transcription in bacteria.

Transcription in bacteria is controlled by multiple molecular mechanisms that precisely regulate gene expression. It has been recently shown that initial RNA synthesis by the bacterial RNA polymerase (RNAP) is interrupted by pauses; however, the pausing determinants and the relationship of pausing with productive and abortive RNA synthesis remain poorly understood. Using single-molecule FRET and biochemical analysis, here we show that the pause encountered by RNAP after the synthesis of a 6-nt RNA (ITC6) renders the promoter escape strongly dependent on the NTP concentration. Mechanistically, the paused ITC6 acts as a checkpoint that directs RNAP to one of three competing pathways: productive transcription, abortive RNA release, or a new unscrunching/scrunching pathway. The cyclic unscrunching/scrunching of the promoter generates a long-lived, RNA-bound paused state; the abortive RNA release and DNA unscrunching are thus not as tightly linked as previously thought. Finally, our new model couples the pausing with the abortive and productive outcomes of initial transcription.