Hippocampus/Striatum influence on what is selected from incoming stimuli/information.

Excess dopamine signaling from the striatal memory stream, is thought to lead to a state of aberrant salience for the brain, whereby innocuous stimuli come to be processed as (if) imbued with fear meaning.

Less hippocampus dentate glutaminergic cells, would lead to less GABA inhibitor activity in hippocampus CA3.

Too much GABA inhibiting according to Bast will mean less efficient attentional direction from pre-frontal cortex?

The brain needs a narrative to pull together a reaction to whatever is going on.

The split brain.
Gazzaniga describes - " the amazing capacities of the non-speaking right cerebral hemisphere, and the wild confabulations of the speaking left hemisphere when asked to explain actions and decisions of its disconnected partner"
Gazzaniga found that if the right brain was given an ambiguous set of perceptions - or a situation so opposite that it was difficult to make it coherent, the left brain always made a narrative solution that put sense into the conflicting positions ]

A clearly presented account of how a story might be expected to explain an abnormal juxtaposition of incompatible incoming stimuli/information


Striatum deals with incoming overload
In a seminal 2006 research article

poldrack interviewed

"you and your fellow researchers report findings from a study using "functional magnetic resonance imaging" that found "heavy striatal engagement" occurring during multitasking. What is "heavy striatal engagement"? What does your research tell us about the cost of task switching while trying to learn? At the same time, why do so many students believe in "the myth of multitasking"—that they can do many tasks at once and, in fact, perform far better under these circumstances?
Russ: "Heavy striatal engagement" is a lot less titillating than it sounds. The striatum is a part of what are called the brain's "basal ganglia."

These are a set of brain areas located deep in the brain, which receive input from many parts of the cerebral cortex and then send information back to those same regions via a set of "loops," which are really just connections between several brain areas that loop back on themselves. The basal ganglia are involved in nearly every aspect of thinking and behavior, but we think they play a particular role in selecting which of several actions one will perform in a given situation, and especially in developing new habits and routines.

In the study that you mention, we asked people to learn how to categorize set of cards that were presented on the screen; the subjects had to learn by trial and error, which sets of cards went with each category. In one part of the experiment, they were able to do this while focused on the task. In another part, they had to try to learn another categorization problem while also performing a secondary task, which involved keeping a running count of the number of times that a particular sound happened. This is a difficult multitasking situation! What we found was that people could learn the categorization task under either single-task or multitasking conditions, but that they learned it differently in the two cases.

In the single task conditions, they used a part of the brain called the hippocampus, which is known to be important for creating rich and flexible memories of the past. Fitting with this, when we tested for their ability to generalize the knowledge that they had gained (e.g., by testing using a different kind of test), subjects were able to generalize the knowledge well.

What we saw when subjects learned under multitasking conditions was quite different. Instead of using the hippocampus, subjects instead used the striatum to learn the task. Based on this, we suspected that the knowledge that they had gained would not be as flexible, and this is exactly what we found; unlike the problems that they learned under focused conditions, they were not able to generalize the knowledge that they had learned while multitasking when we tested them in a different way. It's a fairly long stretch from this research to the classroom, but the results at least suggest that even if multitasking doesn't prevent people from learning, it can change how they learn in ways that are not beneficial."

Why people believe in the "myth of multitasking" is a great question, and I don't think we have a good answer.
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