I'd realign time2 to time1 for each subject (this assures that each
brain region is aligned across time). Realign should be sufficient for
short time intervals. Then, for the 1st level analysis, you want 4
sessions. Then you setup the contrasts at the first level (fmri design
specification). You do not need the factorial design at the first
level.
If you have 1 task and use temporal derivative:
1 0 1 0 -1 0 -1 0 should be the correct contrast
Second-level analyses require multiple subjects, if you are wanting
the effects in a single subject, it needs to be done at the first
level.
On Tue, Apr 28, 2009 at 5:25 PM, Sue Cho <[log in to unmask]> wrote:
> Hi,
>
> I'm sorry for not responding earlier. The time interval between T1 and T1 is
> about one month.
>
>
> Sue.
>
> On Wed, Apr 22, 2009 at 8:19 AM, MCLAREN, Donald <[log in to unmask]>
> wrote:
>>
>> How much time occurs between time1 and time2?
>>
>> 2009/4/21 Sue <[log in to unmask]>:
>> > Dear SPM users,
>> >
>> > I collected data at two different time points from the same individual
>> > and want
>> > to compare Time1 data to Time2 data.
>> >
>> > The task is a picture naming task and it alternates with fixation
>> > (viewing a
>> > cross). It is an event-related design and consists of 2 runs. The naming
>> > list
>> > consists of two categories: living (e.g., apple) and non-living (e.g.,
>> > chair).
>> >
>> > We defined contrast for naming as the following (2 runs combined, time
>> > derivative included).
>> >
>> > 0 0 1 0 1 0 0 0 1 0 1 0 0 0
>> > (the first 2 zeros for cross, 1 0 for living, 1 0 for non-living,
>> > repeated for the
>> > second run)
>> >
>> > The same contrast was used for Time1 data and Time2 data, respectively.
>> >
>> > I want to know how I should define contrast in order to compare Time1 to
>> > Time2 at the first level or if there is any other way to do it.
>> >
>> > Thank you so much in advance.
>> >
>> > Sue.
>> >
>>
>>
>>
>> --
>> Best Regards, Donald McLaren
>> =====================
>> D.G. McLaren
>> University of Wisconsin - Madison
>> Neuroscience Training Program
>> Office: (608) 265-9672
>> Lab: (608) 256-1901 ext 12914
>> =====================
>> This e-mail contains CONFIDENTIAL INFORMATION which may contain
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>
>
--
Best Regards, Donald McLaren
=====================
D.G. McLaren
University of Wisconsin - Madison
Neuroscience Training Program
Office: (608) 265-9672
Lab: (608) 256-1901 ext 12914
=====================
This e-mail contains CONFIDENTIAL INFORMATION which may contain
PROTECTED HEALTHCARE INFORMATION and may also be LEGALLY PRIVILEGED
and which is intended only for the use of the individual or entity
named above. If the reader of the e-mail is not the intended recipient
or the employee or agent responsible for delivering it to the intended
recipient, you are hereby notified that you are in possession of
confidential and privileged information. Any unauthorized use,
disclosure, copying or the taking of any action in reliance on the
contents of this information is strictly prohibited and may be
unlawful. If you have received this e-mail unintentionally, please
immediately notify the sender via telephone at (608) 265-9672 or
email.
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