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David Duncan’s fMRI & EEG Results. Working memory task. cue stimuli. delay. response. 1 sec. 1 sec. 1 sec. 1 sec. 8 sec. 1 sec. Remember Faces Ignore Scenes. +. Remember Scenes Ignore Faces. +. Passively View. +. • Equivalent perceptual, bottom-up information.
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Working memory task cue stimuli delay response 1 sec 1 sec 1 sec 1 sec 8 sec 1 sec Remember Faces Ignore Scenes + Remember Scenes Ignore Faces + Passively View + •Equivalent perceptual, bottom-up information. •Differences in activity mediated by top-down signals.
Younger DD Older fMRI Working Memory Performance Accuracy Face Memory Scene Memory Response Time Face Memory Scene Memory
Younger DD Older EEG Working Memory Performance Accuracy Face Memory Scene Memory Response Time Face Memory Scene Memory
Scene-selective Area Modulation p <.001 Ignore Scenes Remember Scenes BOLD Signal Enhancement Suppression Remember Scenes Passive View Ignore Scenes Gazzaley, A. et al.Journal of Cognitive Neuroscience (2005)
Normal Aging Younger Older Participants = 18 subjects Age = 23.5 years (19-30) Education = 15.6 years (12-19) Participants = 18 subjects Age = 67 years (60-77) Education = 15.4 years (12-19) Older subjects reflect “normal” aging No medications, depression, dementia Equivalent to age-matched controls on 11 tests of executive & memory function
Within-group comparison Older (60-77 y.o.) Younger (19-30 y.o.) Passive View Passive View Remember Scenes Remember Scenes Ignore Scenes Ignore Scenes Gazzaley, A. et al.Nature Neuroscience (2005)
Across-Group Comparisons Enhancement Suppression Younger Older Younger Older Enhancement Index (Remember-Passive) Suppression Index (Passive-Ignore)
R L R L Fusiform Face Area (face-selective area) Parahippocampal Place Area (scene-selective area) These functionally defined regions serve as regions of interest
Older (60-77 y.o.) Younger (19-30 y.o.) Passive View Passive View Remember Scenes Remember Scenes Ignore Scenes Ignore Scenes Gazzaley, A. et al.Nature Neuroscience (2005) David Duncan (49 y.o.) Passive View Remember Scenes Ignore Scenes
Top-down Index Comparisons Enhancement Older Younger David Duncan Suppression David Duncan Younger Older
Top-down modulation Bottom-up processing Neural Basis of Top-down Deficit
fMRI Behavioral Results EEG Behavioral Results Accuracy: Faces Y = 90%, O = 78% (P = 0.001), DD= 83% Scenes Y = 92%, O = 81% (P < 0.001), DD= 90% RT: Faces Y = 1381ms, O = 1673ms (P < 0.005), DD=1307 Scenes Y = 1348ms, O = 1588ms (P < 0.05), DD=1082 Accuracy: Faces Y = 95%, O = 88% (P = 0.001), DD = 95% Scenes Y = 90%, O = 83% (P < 0.001); DD = 92% RT: Faces Y = 1193ms, O = 1302ms (NS), DD=894 Scenes Y = 1304ms, O = 1366ms (NS), DD=1191