Chase: Cognitive psychologists attend a conference like this because they are
interested in finding out what physiological psychology can offer psychology.
Without a doubt, the two "physiological" research programs that had the
greatest impact on concepts in psychology are the single-unit recordings of Hu bel
and Wiesel ( 1962) and the split-brain studies of Sperry and Gazzaniga
( Sperry, 1961). For better or worse, cognitive theory has been influenced
greatly by these physiological investigations. The question that is at the core of
this panel's assignment is, how can ERP research contribute to our under-
standing of physiological mechanisms and cognitive processes? It's quite obvi-
ous by now that electrophysiological research does have a lot to say about cog-
nitive processes. For example, before coming to this conference I thought that
filter theory was a dead issue. But it is clear from Hillyard's work that the
N100 does have something to do with attention. From Donchin's work it is
clear that something interesting is happening with respect to expectancy and
P300.

So on what issues will electrophysiological research have an impact? As
Shiffrin said, from a chronometric point of view we definitely need a physiolog-
ical model of reaction time. Research on the ERP can tell us what the physio-
logical mechanisms of reaction time are. There is no question that ERP
research can help in changing our ideas about attention. There are ideas about
limited capacity mechanisms. I think that as cognitive psychologists we believe
that we are measuring limited capacity mechanisms, and I am sure that ERP
research can tell us more about that. I personally think that the propositional

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