The temporal order judgment paradigm: subcorticalattentional contribution under exogenous and endogenouscueing conditions

• Published in: Neuropsychologia Vol. 37; no. 5; pp. 511 - 520
• Main Authors: Zackon, David H, Casson, Evanne J, Zafar, Aftab, Stelmach, Lew, Racette, Lyne
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-02-1999
• Subjects: Naso-temporal asymmetry; Subcortical processing; Visual attention; Visual pathways; Subcortical processing; Visual attention; Visual pathways; Naso-temporal asymmetry
• ISSN: 0028-3932; 1873-3514
• DOI: 10.1016/S0028-3932(98)00134-1

The role of subcortical attentional processing was investigated under exogenous andendogenous cueing conditions. As retino-tectal projections arise predominantly from the nasalretina i.e., temporal hemifield, subcortical attention should be distributed asymmetrically undermonocular viewing conditions with a temporal hemifield advantage. We compared the results ofmonocular and binocular viewing conditions using a temporal order judgment (TOJ) paradigm.Subjects fixated a centrally located cross and two stimuli were presented with a variable onsetasynchrony. Three experiments were conducted: no cue, exogenous cue and endogenous cue.Subjects reported which stimulus seemed to appear first. An effect consistent with subcorticalprocessing was found under exogenous cueing conditions. No such effect was found underendogenous cueing conditions. We believe that subcortical attentional processing in response toan exogenous cue facilitates rapid shifts in attention towards environmental stimuli. We found noevidence for subcortical processing in voluntary directed attention and believe this process to becortical in nature.