A comparison of upper vs. lower and right vs. left visual fields using lexical decision

Area of Science:

• Cognitive Psychology
• Neuroscience
• Visual Perception

Background:

• The human visual system exhibits functional asymmetries between the upper and lower visual fields.
• Understanding these differences is crucial for comprehending visual processing and word recognition mechanisms.

Purpose of the Study:

• To investigate functional differences in word recognition between the upper visual field (UVF) and lower visual field (LoVF).
• To explore the influence of visual hemifield and semantic priming on these visual field asymmetries.

Main Methods:

• Utilized the lexical decision task to assess word-nonword discrimination.
• Presented word stimuli in various visual fields (UVF, LoVF, RVF, LVF) and manipulated eccentricity.
• Employed related word primes and semantically constraining sentence primes.

Main Results:

• Word recognition was significantly faster and more accurate in the UVF compared to the LoVF.
• The UVF advantage was consistent across different eccentricities and visual hemifields (RVF/LVF).
• Semantic priming generally enhanced visual field differences, with sentence primes specifically boosting the right visual hemifield (RVF) advantage.

Conclusions:

• The superiority of the UVF in word recognition is not solely attributable to perceptual or attentional factors.
• Evidence suggests that top-down information flow plays a significant role in UVF advantages.
• These findings contribute to understanding the neural basis of visual field asymmetries in language processing.