Functional brain mapping during free viewing of natural scenes

Abstract

Abstract:Previous imaging studies have used mostly perceptually abstracted, idealized, or static stimuli to show segregation of function in the cerebral cortex. We wanted to learn whether functional segregation is maintained during more natural, complex, and dynamic conditions when many features have to be processed simultaneously, and identify regions whose activity correlates with the perception of specific features. To achieve this, we used functional magnetic resonance imaging (fMRI) to measure brain activity when human observers viewed freely dynamic natural scenes (a James Bond movie). The intensity with which they perceived different features (color, faces, language, and human bodies) was assessed psychometrically in separate sessions. In all subjects different features were perceived with a high degree of independence over time. We found that the perception of each feature correlated with activity in separate, specialized areas whose activity also varied independently. We conclude that even in natural conditions, when many features have to be processed simultaneously, functional specialization is preserved. Our method thus opens a new way of brain mapping, which allows the localization of a multitude of brain areas based on a single experiment using uncontrolled, natural stimuli. Furthermore, our results show that the intensity of activity in a specialized area is linearly correlated with the intensity of its perceptual experience. This leads us to suggest that each specialized area is directly responsible for the creation of a feature-specific conscious percept (a microconsciousness). Hum. Brain Mapp. 21:75-83, 2004.

Event perception: A mind-brain perspective.

“…Another temporal region (parahippocampal gyrus) that had previously been found to be sensitive to pictures of buildings and spaces responded selectively when establishing shots or other wide-angle views were presented. This paradigm established that these areas, which previously had been explored using highly controlled picture judgment tasks, responded selectively in the context of realistic dynamic movies (see also Bartels & Zeki, 2004).…”

Natural world physical, brain operational, and mind phenomenal space–time

“…Indeed, it has been shown experimentally that the intensity with which each of these features is perceived correlates linearly with the intensity of activity in the regions specialized for each feature [203]. Moreover, it was shown consistently across subjects that the maximum activity of areas with known specialization correlated with the presence of the corresponding feature [204].…”

“…Indeed, it has been shown that a set of 'feature extracting neural assemblies' decompose in parallel the complex stimulus into so-called fragments of sensation: distinct neuronal assemblies have a preference to process distinct features (a preference for color, shape, motion, smell, etc.) [201,203]. biochemical nature [6]; (c) noncorrelated or only weakly correlated with cognition, behavior, and consciousness levels: For example, it tends to vary insignificantly in awake, sleeping, and anesthetized brains [112].…”

Language structure in the brain: A fixation-related fMRI study of syntactic surprisal in reading

“…Because effects in an fMRI study may be influenced by inclusion of a secondary task, our general approach is to understand complex cognitive processes in a natural context, an approach that has been used with auditory narratives (Brennan et al, 2010;Wilson et al, 2008), natural reading (Altmann et al, 2014;Choi et al, 2014;Choi and Henderson, 2015), film viewing (Bartels and Zeki, 2004;Hasson et al, 2004;Nishimoto et al, 2011), and active photograph viewing Stansbury et al, 2013). Here we asked participants simply to read naturally for comprehension.…”