2. Neuroimaging studies of normal aging The effects of normal aging on cognition Neuroimaging as a scientific tool The physiological basis of cognitive changes in normal aging

3. Attention Executive function Visuospatial skills Memory Language

4. Working Memory is the ability to maintain and manipulate information over short periods of time necessary to guide behavior

5. 4371506 -----> 4371506 MAINTAIN 4371506 -----> 6051734 MAINTAIN and MANIPULATE

6. Where’s the flag? Is this supposed to be fun? Should I kick it?

7. 200 400 600 800 1000 Mean Reaction Time (msec) Task Condition 70s-80s 50s-60s 20s-30s ALONECOUNTINGDIGIT SPAN

9. STRUCTURALFUNCTIONAL Magnetic Resonance ImagingPositron Emission Tomography

10. Structural brain changes with aging changes in brain volume youngold

11. FRONTAL OTHER BRAIN REGIONS

12. STRUCTURALFUNCTIONAL Magnetic Resonance ImagingPositron Emission Tomography

13. OLD YOUNG

17. red = right eye blue = left eye Ocular dominance columnsPrimary visual cortex (V1) SPATIAL RESOLUTION

18. TEMPORAL RESOLUTION

20. + + + CUEDELAYRESPONSE

22. YOUNGELDERLY UNDER RECRUITMENT OVER RECRUITMENT YOUNG OLD NON-SELECTIVE RECRUITMENT

24. 0 200 400 600 800 Reaction Time (msec) 2 Letters6 Letters

25. FASTESTSLOWESTYOUNG

26. FAST ---------------------> SLOW Neural recruitment Information processing speed LESS ---------------------> MORE

27. Memory Load 262 6 500 750 1000 1250 1500 Young Old Reaction Time (msec)

28. FASTESTSLOWEST YOUNG OLD

29. Neural recruitment LESS ------------------------------------------------> MORE FAST ---------------------> SLOW Information processing speed SLOW ---------------------> FAST YOUNGOLD

31. Summary Age-related decline in selective cognitive processes Functional MRI is a powerful method with excellent spatial and temporal resolution to study the physiological basis of cognitive decline in normal aging Evidence for selective prefrontal cortical dysfunction (I.e. under-recruitment) with normal aging Possible neural as well as behavioral compensation

33. EVXRCe time Working memory taskFunctional MRI