Dr. Charles J. Duffy—MD, PhD, and CAS Founder and CEO—began his investigation by conducting cognitive psychophysical studies demonstrating specific deficits in human aging and AD (Tetewsky, 1999; O’Brien, 2001).
This led to studies showing the independence of these deficits from memory deficits (Mapstone, 2003) and attentional deficits (Kavcic, 2003).
Dr. Duffy then expanded the studies, distinguishing deficits related to aging and AD (Mapstone, 2006, 2008, 2010; Velarde, 2012).
Dr. Duffy’s studies of functional impairment led to development of new technologies for recognizing and characterizing cognitive impairment (Monacelli, 2003), including virtual-reality test batteries (Cushman, 2007; 2008).
A series of related studies using a psychophysical approach linked the behavioral research with the neurophysiological research to define the neural mechanisms of impairment in aging and AD (Kavcic, 2008; Fernandez, 2007, 2012, 2013; Jacob, 2014).
Bottom-up (Sensory) and Top-down (Control) Signals
When interconnections emanate from sensory areas, carrying sensory input signals to a part of the brain, they are commonly referred to as bottom-up signals. When those interconnections emanate from motor areas, carrying task-specific control signals to a part of the brain, they are commonly referred to as top-down signals. Each area devoted to a specific brain function receives some combination of both bottom-up sensory signals and top-down control signals.
The Cognivue Solution: Psychophysical Profiles
The Cognivue cognitive psychophysical approach presents sensory signals to activate the perceptual and memory functions of various brain systems. Plus, it provides consistent rotatory response tasks to normalize the influence of top-down control signals.
This combination of approaches provides the opportunity to measure the perceptual and memory functional abilities across select, specific functional domains.
Cognivue manipulates the strength of the bottom-up signals to quantify domain-specific perceptual processing abilities. And superimposes an interfering mask stimuli of varying durations to quantify domain-specific memory processing abilities.
Summary of Clinical Research Related to the Development of Cognivue
More than 20 scientific references and brief summaries of research on clinical populations that included the cognitive psychophysical approach and contributed to the experimental foundations of Cognivue technology can be found below: