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Great, thanks a lot!

Jonathan Peelle wrote:
> Esther,
> 
> Yes, that's exactly what I meant.  Good luck!
> 
> Jonathan
> 
> On Wed, Mar 25, 2009 at 3:13 PM, Esther Fujiwara <[log in to unmask]> wrote:
>> Thanks very much for your responses everyone! This does make a lot of sense.
>> Just to verify, I would have 9 conditions (blocks A,B,C, events 1,2) set up
>> like this:
>>
>> blocks (duration 30)
>> A
>> B
>> C
>>
>> events (duration 0)
>> A1
>> A2
>> B1
>> B2
>> C1
>> C2
>>
>> which equals 9 conditions (i.e., not A1, A2, B1, etc. with 30 duration).
>>
>> Thanks for verifying!
>>
>> Esther
>>
>>
>> Jonathan Peelle wrote:
>>> Hi Esther
>>>
>>> A quick response to your last question:
>>>
>>>> Quickly with regard to the conditions: I want to use a factorial design,
>>>> so
>>>> I believe I need to set up my conditions as indicated (6 total).
>>>>
>>>> The way I am doing this right now is as follows: I include the block
>>>> onsets
>>>> together with event onsets in the same condition file, i.e., if one run
>>>> has
>>>> two blocks and five events per block, the input would look like this:
>>>>
>>>> onsets:
>>>> 14 16 21 22 24 25  136 137 145 149 150 158
>>>> duration:
>>>> 30 0 0 0 0 0 30 0 0 0 0 0
>>> The problem with this approach is that by including both the sustained
>>> and transient activity in the same condition, you make it impossible
>>> to separate the two effects.  I think what you want, as Donald
>>> suggested, is 9 conditions:
>>>
>>> block 1 (duration of 30 sec)
>>> A in block 1 (duration of 0)
>>> B in block 1
>>>
>>> block 2 (duration of 30 sec)
>>> A in block 2
>>> B in block 2
>>>
>>> etc.
>>>
>>> This should let you test for all of the main effects and interactions
>>> in your design.
>>>
>>> I wouldn't think you would need to worry about different shapes of
>>> HRF.  If there is indeed sustained activity during these blocks, then
>>> I would think that the standard SPM convolution with the HRF would
>>> reflect this.  If you did want to use different basis sets, I don't
>>> think there is a way to do this in the GUI; you would probably have to
>>> write some code to do this.
>>>
>>> Hope this helps,
>>>
>>> Jonathan
>>>
>