The Role Of Discrimination In Face Recognition In Garner Interference

Garner paradigm mainly for assessment whether there is interactive effect between the dimensions of stimuli in the information processing, the emergence of Garner interference indicates that dimensions are not independent, existing research which use this paradigm to discuss whether the relationship between the dimensions in face recognition is independent or dependent get different conclusions. A general principle during perceptual process is relatively high discriminability dimension interference relatively low discriminability dimension that is discrimination effect. Accordingly, the present study discuss the influence of discriminability on Garner paradigm in face recognition, trying to solve why previous studies get inconsistent conclusions, present study mainly answered there questions:First, what is the ERP mark of relatively high and relatively low discriminability on facial recognition? Second, what is the time course of Garner interference and which kind of processing stages did Garner interference participate in? Third, how did discriminability work in Garner interference?The role of discriminability in interference between recognition of facial identity and facial expression were investigated using two Garner's speeded classification tasks. By matching face shapes in identity and matching mouth performing in facial expression, we manipulated the relative discriminability of both identity and expression. The first experiment examined the Gamer interference between recognition of facial identity and facial expression in upright condition, and discussed the corresponding ERPs components, the results showed:1. The ERP mark of relatively high and relatively low discriminability on facial recognition is P3, starting from264to530ms after stimulus onset, relatively high discriminability was associated with a more positive ERP in the occipital region;2. The behavior and ERP results of recognition task of facial identity and facial expression showed that both relatively low discriminability of task and relatively low discriminability of dimension caused Garner interference, there were differences between baseline condition and filtering condition in the reaction time and waveform;3. The time course of Gamer interference ware different between different tasks, Garner interference of recognition task of facial identity occurred in N2, starting from180to260ms after stimulus onset, baseline condition was associated with a more negative ERP in the frontal, central and parietal area, Gamer interference of recognition task of facial expression occurred in P3, starting from264to530ms after stimulus onset, the latency of filtering condition was longer in the parietal area and occipital region of left electrodes.The sceond experiment examined the Gamer interference between recognition of facial identity and facial expression in inversion condition, further investigating the role of discriminability in Garner interference, the results showed:1. Recognition task of inversion facial identity showed that only relatively low discriminability of dimension rather than relatively low discriminability of task caused Garner interference;2. Recognition task of inversion facial expression showed that both relatively low discriminability of task and relatively low discriminability of dimension caused Garner interference.In conclusion:The ERP mark of relatively high and relatively low discriminability on facial information is P3component; Garner interference occurred in N2and P3, involved in the early stage of stimulus evaluation and classification; The level of discriminability is an important factor which determines the interaction of identity recognition and expression recognition, and only relatively low discriminability of dimension rather than relatively low discriminability of task caused Garner interference,dimension with relatively high discriminability yield interference to one with relatively low discriminability.