## 4 Common/Unifying Theoretical-Conceptual Framework
### qEEG Phenotype and Neurophysiological, Cognitive, and Behavioral Traits
#### 4.2.2 Speed of Information Processing  
Even though this domain is dependent on tonic vigilance, it has added significance in relation to normal functioning and neuropsychological.  
The speed of information processing through periodic cycles of sampling and sensory integration determines the pace of perceptual performance and behavior [148,549,550]. In other words, the speed of information processing determines the resolution at which information is sampled and/or processed by cortical neurons, and, therefore, it limits the capacity for storage, transfer, and retrieval of information in the brain [551, 552, 553]. In such a way, the speed of information processing regulates the overall amount of information that reaches the cortex and is related to reaction time, speed, and capacity of cognitive and motor task performance, cognitive preparedness, temporal integration of information across the senses, as well as reasoning ability.  
The speed of information processing is an individually stable trait (varies within an individually specific range) and is predictive of the individual's reaction and decision times, attention, and working memory performance across the age span [21,69,78,144,553,554,561, 553, 554,555, 556, 557, 558, 559, 560, 561].  
The speed of information processing is expressed along the health-pathology continuum, where slowed information flow is observed in sorrow and fear emotions, physiologic and pathologic aging, mild cognitive impairment and AD, vascular dementia, psychosis and schizophrenia, ADHD, chronic fatigue, burnout syndrome, and melancholic depression [562, 563, 564,565, 117,119,124,530,532,544,562, 563, 117, 564, 565, 566, 567], whereas an increased speed of information processing is typical for anger, anxious arousal and panic disorder, hyperaroused fatigue (overloading), anxious depression, and PTSD [562, 523]. Additionally, temporality (inner and outer time speed perception) is recognized as an important factor in psychopathology [568, 569, 570], where an imbalance between inner and outer time speed perception was demonstrated. For the transdiagnostic character of the speed of information processing, see [518].  
Importantly, qEEG characteristics are causally related to the speed of information processing [550, 559,561,144,148,549,550,559,561] and the temporal integration of information across the senses [552, 553, 571, 572]. Additionally, qEEG characteristics associated with the speed of information processing have a heritability of 81% [89].  
To summarize, the speed of information processing is controlled by the characteristics of qEEG phenotypes that are thought to function as a timing or gating mechanism in operation processing [573]: shorter-duration qEEG oscillations provide more gating signals per unit of time and, thus, result in faster information-processing rates and shorter RTs, whereas longer-duration qEEG oscillations provide fewer gating signals and lead to slower processing rates and longer RTs [574]. This is in line with 'physiological ability' (introduced by Wedensky [575]), defined as the capacity of the system to perform a certain amount of complete work cycles per unit of time [576]. Additionally, alterations in the speed of information processing are characteristic of various neuropsychological.