The effect of acute ethanol challenge on global visuospatial attention: Exaggeration of leftward bias in line bisection

Abstract

Acute alcohol challenge has been associated with a selective impairment of right hemisphere function. A hallmark of visuospatial neglect syndrome is that patients with right hemisphere lesions misbisect horizontal lines far rightward of veridical center. Neurologically intact subjects misbisect lines with a systematic leftward bias (pseudoneglect). Neuroimaging studies in neurologically intact subjects reveal predominant right hemisphere activation during performance of line bisection tasks. The current study assessed whether acute alcohol challenge alters global visuospatial attention. Subjects (N=18; 10 male; strongly right-handed; mean age=23 years) engaged in a forced-choice tachistoscopic line bisection task in both ethanol challenge (mean BAC=.077) and no ethanol control conditions. Mean leftward bisection error in the control challenge condition was −0.238 degrees visual angle (1.05% line length), and leftward bisection error significantly increased (p=.001) under ethanol challenge (−0.333 degrees visual angle, 1.47% line length). Mean bisection precision in the control condition was 0.358 degrees visual angle (1.58% line length); bisection precision significantly deteriorated (p=.008) under ethanol challenge (0.489 degrees, 2.17% line length). Decreased bisection precision indicates that ethanol disrupts the fidelity of visuospatial performance. The exaggerated leftward bisection error implies that ethanol may exert a differential effect on left versus right hemispheric function with respect to the control of global visuospatial attention.

Hemifield asymmetry in the potency of exogenous auditory and visual cues

“…Our results, which reveal significant leftward error in visual line midpoint estimation, are consistent with the established body of evidence that visuospatial attention in neurologically normal subjects exhibits a modest but consistent leftward bias known as pseudoneglect (Bowers & Heilman, 1980; McCourt & Olafson, 1997; Nicholls, Bradshaw & Mattingley, 1999; McCourt & Jewell, 1999; Jewell & McCourt, 2000; McCourt, 2001; McCourt et al, 2005; 2008; Nicholls & Roberts, 2002; Leone & McCourt, 2010; Sosa, Teder-Sälejärvi & McCourt, 2010). While the magnitude of the subtle leftward LB errors of normal subjects contrasts with the florid rightward biases exhibited by neglect patients, both biases are conceptualized to be manifestations of an underlying specialization of neural networks housed in the right hemisphere which deploy visuospatial attention (Heilman & Valenstein, 1979; Heilman & Van Den Abell, 1980; Kinsbourne, 1970; 1977; 1993; Nobre, Sebestyen, Gitelman, Mesulam, Frackowiak & Frith, 1997; Kastner & Ungerleider, 2000).…”

“…It is well established that visuospatial attention in neurologically normal subjects is also distributed asymmetrically, resulting in a modest but systematic and significant leftward deviation of perceived line midpoint (PSE) in line bisection tasks (Bradshaw & Nettleton, 1983; Bradshaw, Nettleton, Nathan & Wilson, 1985; Bradshaw, Nathan, Nettleton, Wilson & Pierson, 1987; McCourt & Olafson, 1997; McCourt & Jewell, 1999; Jewell & McCourt, 2000; McCourt, Garlinghouse & Slater, 2000; McCourt & Garlinghouse, 2000a;b; McCourt, 2001; McCourt, Freeman, Tahmahkera-Stevens & Chaussee, 2001; McCourt, Garlinghouse & Butler, 2001; Foxe, McCourt & Javitt, 2003; McCourt, Garlinghouse & Reuter-Lorenz, 2005; McCourt, Shpaner, Javitt & Foxe, 2008; Leone & McCourt, 2010; Sosa, Teder-Sälejärvi & McCourt, 2010). It leads also to a systematic overestimation of stimulus saliency (e.g., size, brightness, and numerosity) in the left versus right visual hemifield (Luh, Rueckert & Levy, 1991; Nicholls, Bradshaw & Mattingley, 1999; Charles, Sahraie & McGeorge, 2007), to a differential ability to detect changes within the left visual half of complex visual stimulus arrays (Iyilikci, Becker, Gunturkun & Amado, 2010; Du & Abrams, 2010), and to a selective enhancement of memory for objects located within the left half of scenes (Dickson & Intraub, 2009; Della Sala, Darling & Logie, 2010).…”

A selective review of simulated driving studies: Combining naturalistic and hybrid paradigms, analysis approaches, and future directions

“…These combined data allow us to make specific hypotheses regarding intoxicated driving. For example, alcohol disrupts the fidelity of visuospatial performance, especially for more complex images, likely by interfering with higher order visual and parietal circuits and interpretation of complex images may be more affected by alcohol intoxication (Leone and McCourt 2010; Miller and Fillmore 2010). In addition, a frontal-parietal network was identified by (Van Horn, et al 2006) as most affected by alcohol consumption, and modulated by visual feedback.…”

Biases of spatial attention in vision and audition

“…It is well established that visuospatial attention in neurologically normal subjects is asymmetrically distributed as well, resulting in a modest but systematic and significant leftward deviation of perceived line midpoint in line bisection tasks (Bradshaw, Nathan, Nettleton, Wilson & Pierson, 1987; McCourt & Olafson, 1997; McCourt & Jewell, 1999; Jewell & McCourt, 2000; McCourt, Garlinghouse & Slater, 2000; McCourt & Garlinghouse, 2000a;b; McCourt, 2001; McCourt, Freeman, Tahmahkera-Stevens & Chaussee, 2001; McCourt, Garlinghouse & Butler, 2001; Foxe, McCourt & Javitt, 2003; McCourt, Garlinghouse & Reuter-Lorenz, 2005; McCourt, Shpaner, Javitt & Foxe, 2008; Leone & McCourt, 2010), a left hemifield bias in perceived luminance in the greyscales task (Nicholls, Bradshaw & Mattingley, 1999; Nicholls & Roberts, 2002), a left hemispatial bias in perceived stimulus size (Nicholls, Bradshaw & Mattingley, 1999; Charles, Sahraie & McGeorge, 2007) and numerosity (Luh, Rueckert & Levy, 1991; Nicholls, Bradshaw & Mattingley, 1999), and a left hemifield advantage in the processing of faces (Levy & Heller, 1981). This constellation of left-biased asymmetries of spatial attention is called pseudoneglect (Bowers & Heilman, 1980; Jewell & McCourt, 2000).…”