We believe that the decrease in the BOLD signal in the above mentioned neural structures refers to a higher externally cued cognitive involvement in the anticipation phase for more preferred brands compared to less preferred brands, resulting in a higher suppression of internally generated information processing.
These observations are consistent with a double dissociation of NB and MS cholinergic systems' contributions to processing external and internal sources of information and provide further evidence for the septohippocampal system's involvement in processing internally generated cues.
Recent studies have supported a role for the septohippocampal system in the online processing of internally generated cues.
For example, the frontopolar cortex and the precuneus were more activated for ER than for VA, possibly reflecting retrieval mode and processing of internally generated stimuli, respectively.
Conscious awareness is needed to be able to report whether the stimulus was visible or not (Lamme, 2003), but even in such an enhanced state of target processing, the internally generated source overruled the external sensory input, resulting in decreased sensitivity for the detection of the ball contact moment in causally linked scenes.
On the other hand, neuro-cognitive activity with no obvious trigger in the external environment is assumed to reflect the processing of internally generated signals (the offline mode).
There is now good evidence to suggest that different structures are involved in the processing of internally generated versus externally generated events (Lieberman, 2007; Reiman et al., 1997), and this distinction is blurred by script-driven imagery procedures.
Taken together, the chronic and persistent pain of FM appears to change a patient's brain responses during the processing of both externally driven information and internally generated thoughts.
It may be that such effects still depend on the competition for processing resources that always exists in the environment (whether external or internally generated), although admittedly this assumption is difficult to quantify and test.
They are consistent with information processing accounts that link worry to increased rates of stimulus-independent, internally generated task unrelated thoughts; and suggest that this may involve an interplay between regions of the brain that support self-referential processing and others (namely, DLPFC) that have been implicated in reasoning (Goel and Dolan 2003).
