When shapes are more than shapes: perceptual, developmental, and neurophysiological basis for attributions of animacy and theory of mind

Abstract

Among a variety of entities in their environment, what do humans consider alive or animate and how does this attribution of animacy promote development of more abstract levels of mentalizing? By decontextualizing the environment of bodily features, we review how physical movements give rise to perceived animacy in Heider-Simmel style animations. We discuss the developmental course of how perceived animacy shapes our interpretation of the social world, and specifically discuss when and how children transition from perceiving actions as goal-directed to attributing behaviors to unobservable mental states. This transition from a teleological stance, asserting a goal-oriented interpretation to an agent's actions, to a mentalistic stance allows older children to reason about more complex actions guided by hidden beliefs. The acquisition of these more complex cognitive behaviors happens developmentally at the same time neural systems for social cognition are coming online in young children. We review perceptual, developmental, and neural evidence to identify the joint cognitive and neural changes associated with when children begin to mentalize and how this ability is instantiated in the brain.

Keywords: Heider and Simmel; agency; animacy; cognitive development; default-mode network; motion perception; social cognition; theory of mind.

Figure 1

Single frame of Heider-Simmel animation designed by Castelli et al. (2000), depicting a mother who persuades child to go out, conveying theory of mind. Adapted with permission.

Figure 2

Rational goal-directed behavior of a shape moving towards the other by avoiding a barrier (familiarization) (A). (B, C) Depict test trials where in the absent of the barrier, the animate object either travels along the same but now inefficient trajectory, or on a straight path to the goal, as expected from a rational teleological stance. Frames adapted with permission from redrawings of Gergely et al. (1995) by Gergely and Csibra (2003).

Figure 3

Chasing (A) and random (B) animations showing goal-directed path following and undirected behavior, as shown to macaques and squirrel monkeys in the studies of Atsumi et al. (2017) and Atsumi and Nagasaka (2015). Both groups of monkeys exhibited an understanding of directedness by attributing goals to the chaser. Adapted with permission.

Figure 4

Overlap between the default-mode network (DMN), social cognition, and theory of mind. Similarities exist at the posterior cingulate cortex (PCC), the medial prefrontal cortex (mPFC), and the temporo-parietal junction (TPJ). Adapted from Mars et al. (2012) (CC-BY-NC 3.0).

Figure 5

Subdivisions of the DMN. The vmPFC (green), through connections with the MTL and the IPL, represents self-relevant thought. The amPFC (yellow) connects to the PCC to draw distinctions between the self and others. The dmPFC (blue) is involved in reasoning about others together with the TPJ. Adapted from Li et al. (2014) (CC-BY 3.0).

Figure 6

Resting-state networks at birth. Primary visual (A), bilateral sensorimotor (B), bilateral auditory (C), proto-DMN, consisting of the lateral parts of the cerebellum, the posterior mid-parietal areas including the precuneus, and the posterior lateral parietal cortex (D), and prefrontal (E) networks. Adapted from Fransson et al. (2007). Copyright (2007) National Academy of Sciences.