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Project

THE OVERLAP BETWEEN SOCIAL MENTALISING AND ATTENTIONAL REORIENTING: THE ROLE OF THE TEMPORO-PARIETAL JUNCTION (FWOAL556)

Our position is that the overlap between the non-social orientation function and the social agency function
at the TPJ is no coincidence, but points to a fundamental process shared by these orientation and agency functions. Exploring this shared underlying process will increase our understanding of the mechanisms that allow humans to infer the agency of others, without visual input from moving body parts.
The TPJ is greatly expanded in the human brain in comparison to monkeys. Our hypothesis therefore is
that the capacity for detecting agency grew out of the evolutionary older capacity to orient attention to important and relevant objects. We see two possible mechanisms that accomplish this. A first mechanism is that the posterior part of the superior temporal sulcus (pSTS), which is a multisensory area known to detect biological movement, provides input to the TPJ which then simply decides (by combining e.g. proprioceptive and visual input) whether the observed biological movement is from the self or another agent. In all cases, goal-directedness of the movement is considered the default.
Another mechanism is that the TPJ infers the goal of the biological motion by its observed end-state (e.g.,
bringing food to the mouth signals the goal of eating). Here, goal-directedness is not a default, but inferred from the anticipated end-state of the motion. A single-cell study on rhesus monkeys documented that saliency to motion in the parietal area can be modulated by more abstract properties such as learned motion categories (Freedman and Assad, 2006). In similar ways, perhaps, goal relevance is also a higher-order category that the TPJ can abstract and learn. Note that both explanatory mechanisms need not to exclude each other; it is possible that the first agency-sensitive mechanisms might be supplemented by a second goalsensitive mechanism.
Since both hypothetical mechanisms are very close to each other, our prime goal is not to distinguish
between these two. Regardless of which mechanism might be involved, we assume that a ny biological action is considered relevant for the TPJ in order to determine its agency and goal. This sensitivity to relevance is what it also shares with attentional orienting, and which might explain why there is common activity in the TPJ. Our research strategy for unraveling the underlying processing mechanism of this common activity is to work bottom-up, that is, to start with the Posner reorientation task and end with social agency tasks.
1. We first unpack Posner's cueing task, specifically by exploring to what extent it can be modulated by social agency.
2. Our second step is to investigate how much the Posner's task depends on perceptual (e.g., visual) categories or more abstract categories such as goals. We do this by using modified reorienting task with two objects, with only one of them that fits a given category. We explore to what extent these different categories in Posner's modified tasks use common process resources.
3. Next we investigate to what extent inferences of agency are dependent on contextual information, providing further evidence that perceivers often use agency as a default condition given the appropriate contextual conditions
Date:1 Jan 2010 →  31 Dec 2013
Keywords:non-profit organisations, talent management, rating scales, sleep, attention, social neuroscience, implicit learning
Disciplines:Psychology and cognitive sciences