Two types of attention
Published: 01-27-2015 Edited: 02-12-2015
- There are two types of attention which more or less impact the rest of the brain. These two types are on different ends on a continuum and are antagonistic with each other, this means increasing one type of attention decreases the other. It is imporant to not confuse these with other concepts of top-down and bottom-up in the brain. Top-down and bottom-up is a concept which is used in many fields to describe how dynamics are moved, not only neuroscience, top-down means that signal starts from top and bottom-up means signals comes from the bottom.
Top-down and bottom-up are also called modulations of attention, this is because they influence attention in different ways.
Both top-down and bottom-up attention are maintained by similar parts of the brain. Parts of the frontal cortex and parts of the parietal cortex, more specifically the prefrontal-cortex (PFC) and the preparietal-cortex (PPC). 
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In this type attention is driven by stimuli, also called stimuli-driven attention. Attention is directed in the environment which holds the highest level of salience (importance), this is in turn controlled by the brain. This type of attention is also called salience-driven attention. Bottom-up attention is generally related to the external environment. How much salience is attributed to stimuli is controlled by dopamine regulation in the striatum.
Attention is driven by internal goals or targets. This form of attention is also called selective-attention. This form of attention uses more working-memory.  Attention selects where to focus guided by internal goals or targets, receives input and then filters the input from things irrelevant to the internal goal or target. The top-down modulation is done both early and late phases of stimuli-processing. Top-down attention is working with bottom-up attention to select what is relevant to the internal goal or target after salience has been attributed.
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Top-down attention works by maintaining the goal / target in working memory by repetition and avoiding anything which could lead to forgetting of the goal, like salient stimuli until the goal has been accomplished. Bottom-up attention works by first evaluating salient stimuli and if it's interesting enough change course. Bottom-up attention is often called transistent or unbiased because it can change course, top-down attention is called sustained, biased or selective. Selection attention, working memory, top-down attention and proactive cognitive control are very much the same concept and works with the same brain structures. Bottom-up attention is related to reactive cognitive control in the DMC model of working-memory.
But top-down attention can also be used unrelated to external stimuli, called stimuli-independent activity. Some examples of this is mind-wandering, imagination, planning, abstract problem-solving and these forms of top-down attention is shown to recruit an area called the frontopolar cortex. [4,5,8,9] Resolving interference also recruits the frontopolar cortex [3,10]. Managing subgoals also recruit the frontopolar cortex.  Integration of one’s preferences with those of others in the social domain also recruits this area.  Prospective thinking is what makes it possible for people to return thinking about their goals while not being in the present of stimuli relating to the goal.
The frontopolar cortex is activated when internally generated information needs to be available in working memory. [4, 5]
To be continued..
Wikipedia about Top-down and bottom-up design
"Top-down modulation: bridging selective attention and working memory", Adam Gazzaley et al, 2012, Cell Press. 
"Bottom-Up and Top-Down Attention: Different Processes and Overlapping Neural Systems", Fumi Katsuki et al, 2014, The Neuroscientist. 
"Frontal Lobe Mechanisms that Resolve Proactive Interference", David Badre et al, 2005. 
"The frontopolar cortex and human cognition: Evidence for a rostrocaudal hierarchical organization within the human prefrontal cortex", Kalina Christoff et al, 2000. 
"Connecting Long Distance: Semantic Distance in Analogical Reasoning Modulates Frontopolar Cortex Activity", Adam E. Green et al, 2010. 
"The Role of Frontopolar Cortex in Subgoal Processing during Working Memory", Todd S. Braver et al, 2001. 
"Contributions of frontopolar cortex to judgments about self, others and relations", Ana Raposo et al, 2010. 
"Frontopolar cortex mediates abstract integration in analogy", Adam E. Green et al, 2006. 
"Creativity and the brain: Uncovering the neural signature of conceptual expansion", Anna Abraham et al, 2012. 
"Direct Comparison of Prefrontal Cortex Regions Engaged by Working and Long-Term Memory Tasks", Todd S. Braver et al, 2001.