trust is a temporary attachment between humans that pervades our daily lives. recent research has shown that the affiliative hormone oxytocin rises with a social signal of interpersonal trust and is associated with trustworthy behavior (the reciprocation of trust). this commentary reports these results and relates them to the target article's findings for variations in affiliative-related behaviors.

The neural coding metaphor is so ubiquitous that we tend to forget its metaphorical nature. What do we mean when we assert that neurons encode and decode? What kind of causal and representational model of the brain does the metaphor entail? What lies beneath the neural coding metaphor, I argue, is a bureaucratic model of the brain.

Experimental work has revealed causal links between physical cleansing and various psychological variables. Empirically, how robust are they? Theoretically, how do they operate? Major prevailing accounts focus on morality or disgust, capturing a subset of cleansing effects, but cannot easily handle cleansing effects in non-moral, non-disgusting contexts. Building on grounded views on cognitive processes and known properties of mental procedures, we propose grounded procedures of separation as a proximate mechanism underlying cleansing effects. This account differs from prevailing accounts in terms of explanatory kind, interpretive parsimony, and predictive scope. Its unique and falsifiable predictions have received empirical support: Cleansing attenuates or eliminates otherwise observed influences of prior events (1) across domains and (2) across valences. (3) Cleansing manipulations produce stronger effects the more strongly they engage sensorimotor capacities. (4) Reversing the causal arrow, motivation for cleansing is triggered more readily by negative than positive entities. (5) Conceptually similar effects extend to other physical actions of separation. On the flipside, grounded procedures of connection are also observed. Together, separation and connection organize prior findings relevant to multiple perspectives (e.g., conceptual metaphor, sympathetic magic) and open up new questions. Their predictions are more generalizable than the specific mappings in conceptual metaphors, but more fine-grained than the broad assumptions of grounded cognition. This intermediate level of analysis sheds light on the interplay between mental and physical processes.

The human neuroendocrine system is highly sensitive to the social environment. Hormones such as testosterone and cortisol are released in response to a wide variety of social stimuli. The evolutionary functions of this sensitivity are not well understood. Longitudinal monitoring of hormones, behavior, and social environment is a promising research paradigm for solving these evolutionary puzzles.

We agree with the critique of the Residual Normality assumption. Moreover, we challenge monolithic views of functional normality. Throughout life, development and adaptation require variations in cortical functional circuitry within and across individuals. We propose the principle of “coconstructed functionality” which maintains that brain-behavior functional correspondences are dynamically coproduced by neurobiological, experiential, and contextual processes.

We question the behavioral premise underlying Ainslie's claims about hyperbolic discounting theory. The alleged evidence for humans can be easily explained as an artefact of experimental procedures that do not control for the credibility of payment over different time horizons. In appropriately controlled and financially motivated settings, human behavior is consistent with conventional exponential preferences.

Everyday memory tasks often require that researchers focus on output-bound measures of memory. As a result, nonmemorial processes (e.g., report option and grain size) may influence recall accuracy. These nonmemorial processes, usually eliminated by laboratory researchers, have the potential to explain some anomalous results and may even be useful to enhance everyday recollection.

We don't yet have adequate theories of what the human mind is representing when it represents a social group. Worse still, many people think we do. This mistaken belief is a consequence of the state of play: Until now, researchers have relied on their own intuitions to link up the concept social group on the one hand and the results of particular studies or models on the other. While necessary, this reliance on intuition has been purchased at a considerable cost. When looked at soberly, existing theories of social groups are either (i) literal, but not remotely adequate (such as models built atop economic games), or (ii) simply metaphorical (typically a subsumption or containment metaphor). Intuition is filling in the gaps of an explicit theory. This paper presents a computational theory of what, literally, a group representation is in the context of conflict: It is the assignment of agents to specific roles within a small number of triadic interaction types. This “mental definition” of a group paves the way for a computational theory of social groups – in that it provides a theory of what exactly the information-processing problem of representing and reasoning about a group is. For psychologists, this paper offers a different way to conceptualize and study groups, and suggests that a non-tautological definition of a social group is possible. For cognitive scientists, this paper provides a computational benchmark against which natural and artificial intelligences can be held.

This commentary focuses on the two basic assumptions of the E-Z Reader model, discussing the possibility that adjacent words in reading may be processed in parallel rather than serially, and presenting evidence against a cognitive control of eye guidance in reading.