1. The neural bases of intelligence Slide #1 김 민 경 2008. 9. 18 The neural bases of intelligence : A perspective based on functional neuroimaging Newman & Just Center for Cognitive Brain Imaging CMU, Dept of Psychology

2. The neural bases of intelligence Slide #2 Objectives Brain Imaging Technology (primarily fMRI) 를 통해 Human Intelligence 를 포괄적으로 이해하고자 함 Brain Imaging Technology (1) Measure brain activity in individuals during the performance of tasks (2) A new and more comprehensive view of intelligence (3) Insight into the basis of individual differences

3. The neural bases of intelligence Slide #3 Then, what is ‘ Intelligence ’ ? A general Definition “ Goal-directed Adaptive Behavior ” (Sternberg and Salter, 1982) g (general intelligence factor), or fluid intelligence An individual ’ s general problem solving skill (Spearman, 1927) One of the factors that determine g is ‘ mental energy ’

4. The neural bases of intelligence Slide #4 What does correspond to ‘ Mental Energy ’ ? Biological Properties Head Circumference; The larger the brain, the more intelligent the individual Speed of Processing Relationship between reaction time and intelligence ERP (Electrophysiological Recordings) Electrical activity of the brain and cognitive information processing ex) Distinguishable electrical signatures during a reading comprehension task  Indirect and not Comprehensive to account for g, or fluid intelligence

5. The neural bases of intelligence Slide #5 The Neural bases of Intelligence Intelligence is born out of networks of cortical areas  The Investigation of the behavior of these large-scale cortical networks may lead to an explanation of individual differences in ability  Properties of the large-scale neural networks ≈ Mental Energy ≈ A major source of individual difference

6. The neural bases of intelligence Slide #6 Source of individual differences in intelligence 1. Processing Capacity 2. Malleability of processing networks 3. Functional Connectivity 4. Anatomical Connectivity

7. The neural bases of intelligence Slide #7 1) Processing Capacity (1/2) Thinking is biological work requiring resources  Constrained by resource availability Efficiency : less active (resource consumption) in higher-performing individuals : higher ability individuals showed less fMRI-measured activation Amount(cortical resources)   (computational load of a task) : Ability level 과 무관 : ex) Linguistic complexity of a sentence↑, Broca ’ s area & Wernicke ’ s area ↑  Individual may differ in resource availability and/or their efficiency

8. The neural bases of intelligence Slide #8 1) Processing Capacity (2/2)

9. The neural bases of intelligence Slide #9 2) Malleability of processing networks (1/2) The topology of neurocognitive network associated with a given task changes dynamically, adapting itself to the demands of a given task. The ability to dynamically recruit additional resources  a source of individual difference

10. The neural bases of intelligence Slide #10 2) Malleability of processing networks (2/2)

11. The neural bases of intelligence Slide #11 3) Functional Connectivity Communication or Collaboration between various brain areas  The degree of synchronization or efficiency of communication between regions may contribute to individual differences in task performance

12. The neural bases of intelligence Slide #12 4) Anatomical Connectivity The quality of the white matter tracts connecting cortical areas may affect processing speed.  The degree or quality of the anatomical connections may contribute to individual differences

13. The neural bases of intelligence Slide #13 Conclusion Intelligence does not lie in any particular brain region Intelligence arise from a dynamically configured set of brain areas that collaborate adaptively to meet a cognitive challenge Fluid intelligence may represent the neural system ’ s ability to adapt to dynamic changes in a complex cognitive process