Abstract
Purpose: :
Many visual stimuli in the environment around us tend to capture our automatic attention. A go/no-go reaction time psychophysical test showed that the influence of a peripheral cue (S1) on responsivity to a subsequent target depends on the physical characteristics of the go (S2+) and no-go(S2-) targets. When a vertical line (VL) was the S2+ and a small ring (SR) was the S2-, reaction time was shorter at the same location than at the opposite location. However, no reaction time difference between the two locations ocurred when a cross (CR) was the S2+ and the SR was the S2-. There was only attentional effect for the CR when the S2- was a 45º rotated cross (X) (Macea et al, 2006). Trying to confirm these findings, we inverted the relative discriminability of the VL and the CR expecting to obtain the attentional effect.Methods Twelve young adults participated voluntarily. The S1 was a gray ring that could occur in any one of the four corners on a computer screen. The both S2+ were a longer VL and a shorter CR than those in the our other experiments (the main aim was to invert the relative discriminability of both S2+) and the S2- was the SR. These stimuli could occur at the same location of the S1 or at the contralateral horizontal location. The volunteers must respond to each S2+ by pressing a key with their rigth index finger.
Results: :
The reaction times to the CR were longer than to the VL. There was a 33ms attentional effect for both S2+.Conclusion When the S2+ discriminability relative to the S2- is low, as the VL and the small CR, the volunteers probably have difficulty to process only the S2+ and to ignore the S1 and S2-. So, in this case, the S1 captures automatic attention and influences the behavior. These findings may have implications for the rehabilitation of patients with cognitive problems.
Keywords: vision and action • visual search • perception