spm 2002 experimental design daniel glaser institute of cognitive neuroscience, ucl slides from: rik...
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SPM 2002SPM 2002
Experimental DesignExperimental DesignSPM 2002SPM 2002
Experimental DesignExperimental Design
Daniel GlaserDaniel Glaser
Institute of Cognitive Neuroscience, UCLInstitute of Cognitive Neuroscience, UCL
Slides from:Slides from:
Rik Henson, Christian Buchel, Karl Friston,Rik Henson, Christian Buchel, Karl Friston,
Chris Frith, Cathy Price,Ray DolanChris Frith, Cathy Price,Ray Dolan
The Wellcome Department of Cognitive Neurology, UCLThe Wellcome Department of Cognitive Neurology, UCL
London UK http//:www.fil.ion.ucl.ac.uk/spmLondon UK http//:www.fil.ion.ucl.ac.uk/spm
Data transformationsData transformations
RealignmentRealignment SmoothingSmoothing
NormalisationNormalisation
General linear modelGeneral linear model
Statistical parametric map (SPM)Statistical parametric map (SPM)Image time-seriesImage time-series
Parameter estimatesParameter estimates
Design matrixDesign matrix
TemplateTemplate
KernelKernel
Gaussian Gaussian field theoryfield theory
p <0.05p <0.05
StatisticalStatisticalinferenceinference
SPM{T}SPM{T}
speed
isoluminant stimuli (even)
isochromatic stimuli (odd)
V5V5
+
+
StimuliStimuli
A taxonomy of designA taxonomy of designA taxonomy of designA taxonomy of design
• Categorical designsCategorical designsSubtraction Subtraction - Pure insertion and cognitive subtraction- Pure insertion and cognitive subtraction
- Differential event-related fMRI - Differential event-related fMRI
Conjunction Conjunction - Testing multiple hypotheses- Testing multiple hypotheses
• Parametric designsParametric designsLinear Linear - Cognitive components and dimensions- Cognitive components and dimensions
NonlinearNonlinear - Polynomial expansions and neurometric functions- Polynomial expansions and neurometric functions
- Nonlinear event-related fMRI- Nonlinear event-related fMRI
• Factorial designsFactorial designsCategoricalCategorical - Additive factors and pure insertion- Additive factors and pure insertion
- Psychopharmacological designs- Psychopharmacological designs
- Adaptation, modulation and dual-task inference- Adaptation, modulation and dual-task inference
ParametricParametric - Linear and nonlinear interactions- Linear and nonlinear interactions
- Psychophysiological Interactions- Psychophysiological Interactions
A categorical analysisA categorical analysisA categorical analysisA categorical analysis
Experimental designExperimental design
Word generationWord generation GGWord repetitionWord repetition RR
R G R G R G R G R G R GR G R G R G R G R G R G
G - R = Intrinsic word generationG - R = Intrinsic word generation
Differential event-related fMRIDifferential event-related fMRI
Parahippocampal responses to words
BOLD EPI fMRI at 2T, TR BOLD EPI fMRI at 2T, TR 3.2sec. Words presented every 3.2sec. Words presented every
16 secs; (i) studied words or (ii) 16 secs; (i) studied words or (ii) new wordsnew words
BOLD EPI fMRI at 2T, TR BOLD EPI fMRI at 2T, TR 3.2sec. Words presented every 3.2sec. Words presented every
16 secs; (i) studied words or (ii) 16 secs; (i) studied words or (ii) new wordsnew words
Peri-stimulus time {secs}Peri-stimulus time {secs}
SPM{F} SPM{F} testing for testing for
differencesdifferences
studied wordsstudied words
new wordsnew words
SPM{F} testing SPM{F} testing for evoked for evoked responsesresponses
Cognitive ConjunctionsCognitive ConjunctionsCognitive ConjunctionsCognitive Conjunctions
ComponentsComponents
Object Recognition Object Recognition RRPhonological RetrievalPhonological Retrieval PPVisual ProcessingVisual Processing VV
TasksTasks
Object namingObject naming R,P,V,R,P,V,RxPRxPColour namingColour naming P,VP,V
Object viewingObject viewing R,VR,VColour viewingColour viewing VV
The ConjunctionThe Conjunction
[ R,V - V ] & [ R,V,P, [ R,V - V ] & [ R,V,P, RxP RxP - V,P ]- V,P ]R, R, RxPRxP & R = R & R = R
Object recognition responses (R)Object recognition responses (R)
viewing namingviewing naming
A parametric analysisA parametric analysisA parametric analysisA parametric analysis
The [nonlinear] effectThe [nonlinear] effectof time assessed with the SPM{T}of time assessed with the SPM{T}
Nonlinear parametric responses:Nonlinear parametric responses:Nonlinear parametric responses:Nonlinear parametric responses:
Inverted ‘U’ response toInverted ‘U’ response toincreasing word presentationincreasing word presentation
rate in the DLPFCrate in the DLPFCSPM{F}SPM{F}
Regression andRegression and design matrixdesign matrix
42 wpm42 wpm
SPM{F}
Neurometric functions:Neurometric functions:Extrastriate responses to stimuli of increasing duration:Extrastriate responses to stimuli of increasing duration:
Stimulus-specific or contextual effects?Stimulus-specific or contextual effects?
0 exposure duration {ms} 8000 exposure duration {ms} 800
Adaptation of Adaptation of neuronal responsesneuronal responses
AttentionalAttentionalmodulationmodulation
time{ms}time{ms}
SPM{F}SPM{F}
Peri-stimulus timePeri-stimulus time
Hemodynamic responses to words in the left peri-auditory regionHemodynamic responses to words in the left peri-auditory region
60 wpm60 wpm
30 wpm30 wpm
32 secs32 secs
Event-relatedEvent-relatedState-related responsesState-related responses
• BOLD EPI T2* at 2 Tesla TR = 1.7sBOLD EPI T2* at 2 Tesla TR = 1.7s
• 34s epochs of aurally presented words at 0, 10, 15, 30, 60 and 90 words per minute34s epochs of aurally presented words at 0, 10, 15, 30, 60 and 90 words per minute
• 1200 volume time-series1200 volume time-series
Context-sensitive responsesContext-sensitive responsesContext-sensitive responsesContext-sensitive responses
timetimestimulus nstimulus nstimulus n-1stimulus n-1 stimulus n+1stimulus n+1
response nresponse n
interaction between stimuliinteraction between stimuli
Volterra series - a general nonlinear input-output modelVolterra series - a general nonlinear input-output model
response response yy((tt))input input uu((tt))
kernel kernel estimatesestimates
Simulated input
nonlinear saturation
)()(
)(),(
)()(),()}({)(
11
11
0
11 0
i
i
ii
ii
t
iii
t
uu
ty
dduututy
)}({ tu
Nonlinear hemodynamic responsesNonlinear hemodynamic responsesNonlinear hemodynamic responsesNonlinear hemodynamic responses
SPM{F} testing HSPM{F} testing H00: kernel coefficients = h = 0: kernel coefficients = h = 0
kernel coefficients - hkernel coefficients - h
SPM{F}SPM{F}p < 0.001p < 0.001
Nonlinear hemodynamic responses - implicationsNonlinear hemodynamic responses - implicationsNonlinear hemodynamic responses - implicationsNonlinear hemodynamic responses - implications
Hemodynamic response interferenceHemodynamic response interferencein terms of the effect of a prior stimulusin terms of the effect of a prior stimulus
nonlinear saturation
600ms600ms
1400ms1400ms
1400ms1400ms
700ms700ms
42 wpm42 wpm
84 wpm84 wpm
Rate {wpm}Rate {wpm}
Integrated responseIntegrated response
??
42 wpm42 wpm
Rate-dependent responses:Rate-dependent responses:Processing one stimulus in the context of othersProcessing one stimulus in the context of others
ERPs - single wordsERPs - single words
nonlinear interactions
Peri-auditory responses in PET and fMRIPeri-auditory responses in PET and fMRIPeri-auditory responses in PET and fMRIPeri-auditory responses in PET and fMRI
rightrightB
OL
DB
OL
D
Word presentation rateWord presentation rateWord presentation rateWord presentation rate
rCB
FrC
BF
leftleft rightright
Linear rCBFLinear rCBFresponsesresponses
NonlinearNonlinear BOLDBOLD
responsesresponses
A factorial analysisA factorial analysisA factorial analysisA factorial analysis
Time x condition interactions (Time x condition interactions (i.e. adaptationi.e. adaptation))assessed with the SPM{T}assessed with the SPM{T}
Interactions and context-sensitive effectsInteractions and context-sensitive effectsInteractions and context-sensitive effectsInteractions and context-sensitive effects
Context 1Context 1(no naming)(no naming)
Context 2Context 2(naming)(naming)
without A & with Awithout A & with A(e.g.. recognition)(e.g.. recognition)
11 22
4433
A 2 x 2 layoutA 2 x 2 layout
task 1 2 3 4task 1 2 3 4
interaction effectinteraction effect (A x Context)(A x Context)
AA
AA
Context 1Context 1 Context 2Context 2
Object-specific activationsObject-specific activations
Interaction effects in the Interaction effects in the left inferotemporal regionleft inferotemporal region
Context: Context: no naming namingno naming namingad
just
ed r
CB
Fad
just
ed r
CB
F
ComponentsComponentsVisual processingVisual processing VVObject recognition Object recognition RRPhonological retrievalPhonological retrieval PPInteractionInteraction RxPRxP
ConjunctionConjunction(name object - shape) & (view object - shape)(name object - shape) & (view object - shape)= (R += (R + RxP RxP) & R = R) & R = R
InteractionInteraction(name object - shape) - (view object - shape)(name object - shape) - (view object - shape)= (R + = (R + RxPRxP) - R = ) - R = RxPRxP
A PET study of object namingA PET study of object naming
Psychopharmacological studiesPsychopharmacological studies• PET, 6 subjects, 6 conditionsPET, 6 subjects, 6 conditions
• 3 x 2 factorial design, 3 x 2 factorial design, Buspirone x MemoryBuspirone x Memory
sub- supra-sub- supra-
pre-pre-
acute-acute-
post-post-
left parahippocampal left parahippocampal responsesresponses
pre acute post
SCC
timetime
resp
onse
resp
onse
resp
onse
resp
onse
timetime
A direct effect of context = CA direct effect of context = C Context-sensitive effect = S x NContext-sensitive effect = S x N
frequencyfrequency
resp
onse
resp
onse
resp
onse
resp
onse
frequencyfrequency
Dissociating the direct and modulatory effects of contextDissociating the direct and modulatory effects of context
Responses in the right posterior superiorResponses in the right posterior superiortemporal regiontemporal region
to increasing rates (15 - 90 wpm) of word productionto increasing rates (15 - 90 wpm) of word production
whilst repeating words and producing new ones whilst repeating words and producing new ones
7777
8484
rCB
F {
ml/
dl/m
in}
rCB
F {
ml/
dl/m
in}
Interactions between set and event-related responses:Attentional modulation of V5 responses
attention to motion
attention to colour
Non-linear parametric interactionsNon-linear parametric interactionsNon-linear parametric interactionsNon-linear parametric interactions
SPM{F}
Increasing word presentationIncreasing word presentationrate in a subject and patientrate in a subject and patient
with a CVAwith a CVA
Differential responses in theDifferential responses in theleft hippocampusleft hippocampus
Psychophysiological interactionsPsychophysiological interactions
stimulistimuli SetSet
ContextContext
sourcesourcetargettarget
XX
Modulation of Modulation of stimulus-specific stimulus-specific
responsesresponses
Context-sensitiveContext-sensitiveconnectivityconnectivity
sourcesource sourcesource
targettarget targettarget
Psychophysiological interactionsPsychophysiological interactions in the right inferotemporal region:in the right inferotemporal region:
Modulation of face-selectiveModulation of face-selective responses by PPCresponses by PPC
adju
sted
rC
BF
adju
sted
rC
BF
medial parietal activitymedial parietal activity
FacesFaces
ObjectsObjects
Face stimuliFace stimuli
PPCPPC
ITIT
SPM{Z}SPM{Z}
PsychophysiologicalPsychophysiological interactions:interactions:
Attentional modulation ofAttentional modulation ofV2 - V5 contributionV2 - V5 contribution
AttentionAttention
V2V2
V5V5
attention
no attention
V2 activityV2 activity
V5
acti
vity
SPM{T}SPM{T}
timetime
V5
acti
vity