TY - JOUR

T1 - The cortical hyperexcitability index (CHi)

T2 - a new measure for quantifying correlates of visually driven cortical hyperexcitability

AU - Braithwaite, Jason J

AU - Marchant, Rachel

AU - Takahashi, Chie

AU - Dewe, Hayley

AU - Watson, Derrick

PY - 2015

Y1 - 2015

N2 - Introduction. Aberrations of visual experience, including visual hallucinations and visual distortions, are known to be associated with increased cortical hyperexcitability. As a consequence, the presence, intensity and frequency of certain experiences may well be indicative of an underlying increase in cortical hyperexcitability.Methods. The current study presents a new proxy measure of cortical hyperexcitability, the Cortical Hyperexcitability Index (CHi). Two hundred and fifty healthy participants completed the CHi with the results subjected to exploratory factor analysis (EFA).Results. The EFA revealed a three-factor model as the most parsimonious solution. The three factors were defined as: (1) heightened visual sensitivity and discomfort; (2) negative aura-type visual aberrations; and (3) positive aura-type visual aberrations. The identification of three factors suggests that multiple mechanisms underlie the notion of cortical hyperexcitability, providing researchers with new and greater precision in delineating these underlying features.Conclusions. The factorial structure of the CHi and the increased precision could aid the interpretation of findings from neuroscientific (i.e., brain imaging/stimulation) examinations of cortical processes underlying aberrant perceptions across a host of clinical, neurological and pathological conditions. As a consequence, the CHi is a useful and comprehensive proxy measure of cortical hyperexcitability with considerable scientific and clinical utility.

AB - Introduction. Aberrations of visual experience, including visual hallucinations and visual distortions, are known to be associated with increased cortical hyperexcitability. As a consequence, the presence, intensity and frequency of certain experiences may well be indicative of an underlying increase in cortical hyperexcitability.Methods. The current study presents a new proxy measure of cortical hyperexcitability, the Cortical Hyperexcitability Index (CHi). Two hundred and fifty healthy participants completed the CHi with the results subjected to exploratory factor analysis (EFA).Results. The EFA revealed a three-factor model as the most parsimonious solution. The three factors were defined as: (1) heightened visual sensitivity and discomfort; (2) negative aura-type visual aberrations; and (3) positive aura-type visual aberrations. The identification of three factors suggests that multiple mechanisms underlie the notion of cortical hyperexcitability, providing researchers with new and greater precision in delineating these underlying features.Conclusions. The factorial structure of the CHi and the increased precision could aid the interpretation of findings from neuroscientific (i.e., brain imaging/stimulation) examinations of cortical processes underlying aberrant perceptions across a host of clinical, neurological and pathological conditions. As a consequence, the CHi is a useful and comprehensive proxy measure of cortical hyperexcitability with considerable scientific and clinical utility.

KW - Cortical hyperexcitability

KW - Hallucinations

KW - Visual stress

KW - Aberrant experience

KW - Consciousness

U2 - 10.1080/13546805.2015.1040152

DO - 10.1080/13546805.2015.1040152

M3 - Journal article

VL - 20

SP - 330

EP - 348

JO - Cognitive Neuropsychiatry

JF - Cognitive Neuropsychiatry

SN - 1354-6805

IS - 4

ER -