<unk><unk> , or voluntary<unk> , requires a great deal of concentration and focus, and is employed in tasks such as problem solving. This type of<unk>  employs the inhibitory mechanisms of the brain, which help block incoming stimuli that are unrelated to the task at hand. Several parts of the brain are involved in maintaining<unk><unk> , primarily those located in the frontal lobe and the parietal lobe of the brain. Specifically, the mechanism of<unk><unk>  employs the prefrontal cortex (PFC), the anterior cingulate cortex (ACC) and the brain stem's basal ganglia. Some fMRI studies have shown that<unk><unk>  involves changes in the anterior cingulate cortex and the lateral prefrontal cortex, perhaps as a consequence of increased connectivity between these two areas. Evidence also suggests that the right inferior frontal cortex (IFC) plays a specialized role in response inhibition. It seems that this region plays a key role in the integration of bottom-up response-related information and facilitates goal-directed behavior. While these areas of the brain are known to be involved in DAF, their specific molecular mechanisms in the perpetuation of DAF symptoms are not yet known.
Directed attention fatigue
Sundowning
Sleep state misperception
Listener fatigue
Stress concentration
Repressed memory
Wandering 
Anxiety