At a metatheoretical level, interlevel integration poses challenges. The crit-
ical issue is whether and to what extent the mind is divisible and decompos-
able. Emergentism argues that higher levels of organization of the mind have
emergent properties, such as molar-level mental states or intentionality that
cannot be understood at the lower levels of its components (see Cornwell,
1995). Reductionism, on the other hand, holds that phenomena as complex
as mind (with all its properties such as cognition, affect, and conation) can be
understood through interlevel reduction, from the mental to the neuronal
(e.g., Churchland & Churchland, 1995). It appears that from a structural
point of view, cognition and emotion, and emotion and motivation, can be
distinguished from each other. For example, separation of emotion and cog-
nition is evident in brain structures and functions (M. Posner, personal com-
munication, May 12, 2003; see also Dai & Sternberg, chap. 1). With func-
tional neuroimaging techniques available now, we are able to find neuronal
concomitants of many mental processes, such as emotion (Damasio, 1999),
attentional orienting (Derryberry & Tucker, 1994), consciousness (Melt-
zinger, 2000), and even volition or attentional control (Posner & Peterson,
1990), so that psychological constructs of the motivational, emotional, and
cognitive nature can be more precisely defined, and indeed more embodied in
the exact sense of the word. The mind–brain mapping of cognitive, motiva-
tional, and emotional processes can become difficult, however, if complex
cognitive tasks are involved. Using the timescales of intellectual functioning
again, we suspect that the shorter the timescale (e.g., word recognition), the
more likely specific neuronal mechanisms and functions can be pinpointed.
Yet as the complexity of a task and the corresponding timescale of an intel-
lectual act increase (e.g., lengthy text comprehension tasks), the difficulty lo-
calizing precise neuropsyiological mechanisms can increase. Measurable in-
creases in activation in multiple parts of the brain can be obtained, indicating
intensified cognitive efforts (Carpenter, Just, Keller, Eddy, & Thulborn,
1999; Just, Carpenter, Maguire, Diwadkar, & McMains, 2001). However,
here motivation and cognition cannot be teased apart as separate processes at
the brain level. As Kagan (2002) suggested, “a psychological phenomenon is
the result of a cascade of many brain events that occurs over intervals usually
ranging from a quarter-second to several seconds” (p. 21). The mind–brain
relation is likely to be a highly complex, reciprocal (i.e., top-down and bot-
tom-up), part–whole relation (e.g., how individual neural circuits are inte-
grated or coordinated to support certain mental structures and functions),
rather than a unidirectional, linear, one-to-one process. In the case of Car-
penter, Just, and colleagues’ research cited above, intensified brain activity or
motivated cognition is a function of increasing task demands and workload.
One should also espouse the possibility that the content of a person’s inten-
tion (e.g., specific objectives in mind), as well as specific content knowledge a
EPILOGUE: CONCLUDING THOUGHTS 425