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Research Title:
Functional Mapping of Learning Activities in Archaic and Modern Human Brains
Research Organization:
Team Leader
- Hiroki C. Tanabe, Assistant Professor,
Cognitive Neuroscience, Graduate School of Environment Studies, Nagoya University
Co-investigators
- Norihiro Sadato, Professor,
Cognitive Neuroscience, Department of Cerebral Research, National Institute of Physiological Sciences
- Takanori Kouchiyama,
Researcher, Computational Neuroanatomy, Brain Activity Imaging Center, ATR-Promotions
- Naoki Miura, Associate Professor,
Cognitive Neuroscience, Faculty of Engineering, Tohoku Institute of Technology
- Yukinobu Hoshino, Associate Professor,
Intellectual Information Science, School of Systems Engineering, Kochi University of Technology
- Kunihiro Hasegawa, Postdoctoral Research Fellow,
Experimental Psychology, Department of Social and Human Environment, Graduate School of Environmental Studies, Nagoya University
- Keita Mitani, Doctoral Research fellow,
Motion Analysis, Graduate School of Engineering, Kochi University of Technology
Invited Researcher
- Motoaki Sugiura, Associate Professor,
Cognitive Neuroscience, Institute of Development, Aging and Cancer, Tohoku University
- Kei Mizuno, Senior Researcher,
Cognitive Neuroscience, Pathophysiological and Health Science Team, RIKEN Center for Life Science Technologies
Research Objectives
Based on comparative anatomical and neuro-archeological evidence, our research group will examine the working hypothesis that there are differences in learning ability between modern and ancient humans. Specifically, our group will conduct a functional brain mapping study of modern humans in order to localize social learning abilities (related to cultural transmission such as imitation and teaching), and individual learning processes (involved in the making of discoveries and inventing, e.g., trial-and-error learning, thought experiments, and the gaining of insight). These results will then be combined with the quantitative morphological differences between “fossil brains” of ancient and modern humans (comparative morphology) to extrapolate the functional distinctions between the two groups (neuro-archeology). By assuming that morphological differences observed in fossil brains reflect functional differences between modern and ancient human brains, we will investigate the presumed gaps in individual (as opposed to ‘social’) learning abilities between the two types of humans in light of anatomical evidence. This sub-project aims to create an evidence-based model for elucidating the evolution of learning abilities.
Research Methods
(1) Functional Mapping and Analysis of Learning in the Modern Human Brain
Tasks that appropriately involve ‘social’ and ’individual’ learning processes will be created for functional brain imaging (functional MRI and electrophysiological measurements). For this purpose, the following will be considered: the learning hypothesis and the theoretical model adopted for Project B01; the experimental model for the development of stoneware production techniques used in Project A01; and the cultural anthropological model for play-related learning in modern humans constructed in Project A02. Functional brain imaging experiments will be conducted while these tasks are performed, in order to produce learning function maps for the modern human brain as well as to identify the localization and morphology of relevant brain regions in a quantitative manner.
(i) Neural Substrates for Social Learning Skills
Imitative learning, which constitutes a major part of social learning skills, is specific to humans; however, its neural substrates have not yet been fully elucidated. In particular, elucidating the basis of imitative behaviors involves understanding sensory-motor integration, in other words the integration between the perceived intent of actions (sensory component) and the actions themselves (motor component). These features of imitative learning are likely to have different roles and to take place in different brain areas. Functional brain imaging will be used to discriminate between these components.
(ii) Neural Substrates for Individual Learning Processes (Creativity)
Individual learning dynamics include a control process in which the agent adapts to the environment through trial-and-error learning so as to maximize the rewards from the environment (reinforcement learning). To clarify the neural substrates of reinforcement learning, a process shared with other species, our experiments will employ a combination of functional brain imaging techniques and reinforcement learning tasks that have already been established and verified in psychology. In addition, our research will investigate the neural substrates of creativity, a feature believed to be specific to modern humans. Tasks for measuring degrees of creativity will be generated based on the definition of creativity as the production of unprecedented and useful (or influential) ideas in specific social environments. In concrete terms, the model for the development of creativity will be established by incorporating social rewards (approval and praise from others) into the reinforcement learning model, based on the notion that creativity is (a) a result of reinforcement learning and (b) formed in a social context. To pursue this goal, we will create fMRI executable tasks in close and regular collaboration with Project A02, using the cognitive model for play-related creative learning processes. These learning processes will be extracted using cultural anthropological methods and developmental psychological approaches.
(2) Mapping of Learning Functions in the Fossil Brain
Possible differences in learning abilities between ancient and modern humans will be examined by integrating morphological analysis of fossilized brains with functional mapping of the modern human brain. By applying the techniques for superimposing functional maps of the modern human (Friston et al., 2007), we will establish methods for extrapolating brain functions to the reconstructed skull images produced by Project C01. Three-dimensional brain images will be fitted to fossil cranial cavities reconstructed within the computer’s virtual space, along with an indication of the functional topographic map of the brain that will be reconstituted from the functional brain imaging data. Comparative volume quantification will be carried out for the regions mediating specific functions in order to estimate possible functional differences between Homo sapiens and Homo Neanderthalensis (see the figure below).
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