Dear experts,
I would be most grateful for a clarification with regard to an
event-related design.
If two stimulus types always co-occur then it is, of course, problematic to
separate their haemodynamic responses. One way of getting at this might be
to introduce a variable delay between them so that, although A always
occurs with B, there is a variable temporal relationship which might serve
as a basis for differentiating between them. If this is indeed so, does
anyone have a feel for what sort of variability would be required in order
to separate them thus. That is, how far would I need from maximum and
minimum delays between A and B? Perhaps this is unanswerable, but any
thoughts would be gratefully received
Paul Fletcher
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Paul Fletcher,
Research Department of Psychiatry,
University of Cambridge,
Addenbrooke's Hospital,
Hills Road,
Cambridge,
UK
CB2 2QQ
Tel 01223 336 988
Fax 01223 336 581
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