Biases of spatial attention in vision and audition

Abstract

Neurologically normal observers misperceive the midpoint of horizontal lines as systematically leftward of veridical center, a phenomenon known as pseudoneglect. Pseudoneglect is attributed to a tonic asymmetry of visuospatial attention favoring left hemispace. Whereas visuospatial attention is biased toward left hemispace, some evidence suggests that audiospatial attention may possess a right hemispatial bias. If spatial attention is supramodal, then the leftward bias observed in visual line bisection should also be expressed in auditory bisection tasks. If spatial attention is modality specific then bisection errors in visual and auditory spatial judgments are potentially dissociable. Subjects performed a bisection task for spatial intervals defined by auditory stimuli, as well as a tachistoscopic visual line bisection task. Subjects showed a significant leftward bias in the visual line bisection task and a significant rightward bias in the auditory interval bisection task. Performance across both tasks was, however, significantly positively correlated. These results imply the existence of both modality specific and supramodal attentional mechanisms where visuospatial attention has a prepotent leftward vector and audiospatial attention has a prepotent rightward vector of attention. In addition, the biases of both visuospatial and audiospatial attention are correlated.

Localization Error: Accuracy and Precision of Auditory Localization

“…Some potential bias may also be introduced by the reported human tendency to misperceive the midpoint of the angular distance between two horizontally distinct sound sources. Several authors have reported the midpoint to be located 1° to 2° rightward (Cusak et al, 2001;Dufour et al, 2007;Sosa et al, 2010), although this shift may be modulated by listener handedness. For example, Ocklenburg et al (2010) observed a rightward shift for left-handed listeners and a leftward shift for right-handed listeners.…”

Hemifield asymmetry in the potency of exogenous auditory and visual cues

“…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).…”

Related but different: Examining pseudoneglect in audition, touch and vision

“…However, 4 of the 9 participants used by Gori et al, (2014) had lost sight due to retinopathy of prematurity, which has been associated with poorer spatial performance as compared to other early and congenitally blind individuals (Eardley, Edwards, Maloin & Kennedy, 20152016). Of the other research described above, Ocklenburg et al (2010), Sosa et al, (2010), Dufour et al, (2007) and Gori et al, (2014) showing that the leftward bisection bias is reduced or reversed in far space (McCourt & Garlinghouse, 2000;Bjoertomt et al, 2002;Longo & Lourenco, 2010;Gamberini et al, 2008;Longo & Lourenco, 2006Lourenco & Longo, 2009;Varnava et al, 2002) draws into question the comparability of auditory results using extrapersonal stimuli with standard peripersonal tactile and visual line bisection tasks. As a consequenceConsequently, there remains considerable debate about whether leftward auditory pseudoneglect is underpinned by a supramodal system (e.g.…”

“…dextrals pointed to the left of the sound source and sinistrals to the right (see also Corral & Escera, 2008). Sosa, Teder-Sälejärvi and McCourt (2010) created a forced-choice line bisection task. Sosa et al (2010) found, like Dufour, Touzalin and Candas (2007), that the bias in judgement of auditory space was significantly rightward of the midpoint.…”

“…Sosa, Teder-Sälejärvi and McCourt (2010) created a forced-choice line bisection task. Sosa et al (2010) found, like Dufour, Touzalin and Candas (2007), that the bias in judgement of auditory space was significantly rightward of the midpoint. They also found a significant positive correlation in the magnitude of the bisection bias between auditory (rightward bias) and visual (leftward bias) bisections, from which they inferred interhemispheric inhibition for both modalities.…”