Assessment of Stability of Behavioral and Neural Measures of Attention Networks Across Multiple Sessions
Condition: Stability of Attentional Networks Over Multiple Sessions of Computerized Task
Study type: Observational

Summary: 
      The purpose of this research study is to learn more about the stability over multiple
      recording sessions of brainwave activity during a computerized task that measures different
      types of attention.
    

Detailed description: 
      Attention is the backbone of cognitive systems and is requisite for other cognitive processes
      vital to everyday functioning, such as memory, problem solving, language skills, and the
      cognitive control of behavior. Impairments in attention can result from a variety of factors,
      such as brain injury, and neurodegenerative and neurodevelopmental disorders, as well as
      various psychopathologies. A prominent multi-component model of visuospatial attention
      developed by Posner and colleagues conceptualizes visuospatial attention as an "organ system"
      comprised of three independent, yet interactive networks which include: 1) Alerting, the
      generation and maintenance of a vigilant state that facilitates the processing of an upcoming
      stimulus, 2) Orienting, the disengagement, shifting, and reallocation of attention to a
      spatial location, and 3) Executive control, the resolution of conflict among competing
      mutually-exclusive responses that enables selective focus. To aid in understanding of
      attention, the Attention Network Test (ANT) was developed as a brief computerized measure of
      the efficiency of each of these networks and has been extensively used in a variety of
      healthy and clinical populations. Several studies have examined differences in ERPs during
      the ANT in healthy aging and clinical populations such as ADHD, schizophrenia, and traumatic
      brain injury (TBI) but have not conducted repeated sessions of the task to evaluate changes
      over time. While the ANT has been shown to be robustly sensitive to a range of cognitive
      and/or neuropsychological disorders, the reliability of the ANT across multiple sessions,
      particularly in terms of neural activity measures, has not been previously examined. An
      important focus of the proposed research regards the stability of neural measures reflecting
      activity of each of three different attention networks. One method for examining neural
      activity involves time locked electroencephalographic (EEG) recordings of brain activity or
      scalp-recorded brain event-related potentials (ERPs). ERPs can provide insights into the
      neural correlates of cognitive processes elicited by an experimental task as well as the
      neural time course. Particularly relevant to this study, the visual N1, a negative-going ERP
      deflection occurring ~150-200 milliseconds (ms) post-stimulus. N1 amplitude is considered to
      index attentional allocation. Additionally, a later-occurring positive-going deflection
      occurring ~300-ms post-stimulus, P3, reflects processes associated with stimulus evaluation
      and categorization. Previous research in our lab has shown that N1 and P3 are differentially
      sensitive to attention network functioning probed using the ANT in neurologically-healthy
      controls and are sensitive to attentional impairment in TBI survivors. Thus, the study team
      will focus on the stability of N1 and P3 waveforms across the 4 sessions. Previous studies
      have examined reliability and stability of behavioral measures of the ANT by evaluating the
      reliability of reaction time (RT) and error rates over multiple sessions. Ishigami reported
      good temporal stability of network scores across 10 sessions, although some practice effects
      were seen in orienting and executive-control attention networks. Importantly, no prior work
      has examined the temporal stability of ERPs with repeated ANT performance, which is among the
      primary aims of the proposed research. Finally, in an exploratory manner, the investigators
      will extend findings from one of our earlier studies demonstrating altitudinal attentional
      biases for upper vertical space in healthy participants and the absence of such biases in TBI
      survivors. Specifically, the investigators will examine which of three attentional networks
      are sensitive to such biases in healthy controls and determine the ERP signatures of these
      biases.
    

Intervention name(s): Attention Network Task
Intervention type(s): Behavioral
Intervention description(s): The Attention Network Test (ANT) is a computerized cognitive task designed to efficiently probe three independent but interactive attentional networks (alerting, orienting, executive control) in a single task paradigm.
Other intervention name(s): Electroencephalography
Observational model: Case-Only
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Healthy Controls
      
Keywords: cognitive process; visuospatial attention