Embodied Simulation

This chapter provides the key neuroscientific data that enable the reader to follow the case studies. The subheadings are “Cinema, brain and empathy,” in which the reception of film is discussed, and the notion of empathy is introduced with an outline of its history; “Body, brain and neuroscience,” provides a critical account of neuroscience and details of the specific approach used; “From classic cognitivism to embodied cognition,” discusses two mainstream approaches to social cognition, classic cognitivism, and evolutionary psychology; “Motor cognition: Movements and motor goals,” explains why and how the cognitive role of the motor system and its role in visual perception should be reconceived; “Motor cognition: Area F4 and peri-personal space,” provides evidence for the role of the motor system in mapping space; “Motor cognition: Canonical neurons and objects ‘close to hand’,” discusses canonical neurons and their role in object perception; “Motor cognition: Mirror neurons and mirroring mechanisms,” introduces mirror neurons in macaques and mirror mechanisms in humans, and outlines their role in social perception; “Emotions, sensations and embodied simulation,” describes the role of embodied simulation in the perception of the emotions and sensations of others; “The person as a corporeal form between the real world and the world of fiction: Liberated simulation,” introduces the aesthetic specificity of the visual perception model with an explanation of how it could be applied to film viewing in particular and more generally to fiction; and “Brain–body and cinema,” discusses how neuroscience has been applied to the study of film and cinema.

Scalable Semisupervised Functional Neurocartography Reveals Canonical Neurons in Behavioral Networks

Large-scale data collection efforts to map the brain are underway at multiple spatial and temporal scales, but all face fundamental problems posed by high-dimensional data and intersubject variability. Even seemingly simple problems, such as identifying a neuron/brain region across animals/subjects, become exponentially more difficult in high dimensions, such as recognizing dozens of neurons/brain regions simultaneously. We present a framework and tools for functional neurocartography—the large-scale mapping of neural activity during behavioral states. Using a voltage-sensitive dye (VSD), we imaged the multifunctional responses of hundreds of leech neurons during several behaviors to identify and functionally map homologous neurons. We extracted simple features from each of these behaviors and combined them with anatomical features to create a rich medium-dimensional feature space. This enabled us to use machine learning techniques and visualizations to characterize and account for intersubject variability, piece together a canonical atlas of neural activity, and identify two behavioral networks. We identified 39 neurons (18 pairs, 3 unpaired) as part of a canonical swim network and 17 neurons (8 pairs, 1 unpaired) involved in a partially overlapping preparatory network. All neurons in the preparatory network rapidly depolarized at the onsets of each behavior, suggesting that it is part of a dedicated rapid-response network. This network is likely mediated by the S cell, and we referenced VSD recordings to an activity atlas to identify multiple cells of interest simultaneously in real time for further experiments. We targeted and electrophysiologically verified several neurons in the swim network and further showed that the S cell is presynaptic to multiple neurons in the preparatory network. This study illustrates the basic framework to map neural activity in high dimensions with large-scale recordings and how to extract the rich information necessary to perform analyses in light of intersubject variability.

Delay-Period Activity in Visual, Visuomovement, and Movement Neurons in the Frontal Eye Field

In the present study, we examined the role of frontal eye field neurons in the maintenance of spatial information in a delayed-saccade paradigm. We found that visual, visuomovement, and movement neurons conveyed roughly equal amounts of spatial information during the delay period. Although there was significant delay-period activity in individual movement neurons, there was no significant delay-period activity in the averaged population of movement neurons. These contradictory results were reconciled by the finding that the population of movement neurons with memory activity consisted of two subclasses of neurons, the combination of which resulted in the cancellation of delay-period activity in the population of movement neurons. One subclass consisted of neurons with significantly greater delay activity in the preferred than in the null direction (“canonical”), whereas the other subclass consisted of neurons with significantly greater delay activity in the null direction than in the preferred direction (“paradoxical”). Preferred direction was defined by the saccade direction that evoked the greatest movement-related activity. Interestingly, the peak saccade-related activity of canonical neurons occurred before the onset of the saccade, whereas the peak saccade-related activity of paradoxical neurons occurred after the onset of the saccade. This suggests that the former, but not the latter, are directly involved in triggering saccades. We speculate that paradoxical neurons provide a mechanism by which spatial information can be maintained in a saccade-generating circuit without prematurely triggering a saccade.