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We investigated whether an asymmetric relationship between the perception of identity and emotional expressions in faces (Schweinberger & Soukup, 1998) may be related to differences in the relative processing speed of identity and expression information. Stimulus faces were morphed across identity within a given emotional expression, or were morphed across emotion within a given identity. In Experiment 1, consistent classifications of these images were demonstrated across a wide range of morphing, with only a relatively narrow category boundary. At the same time, classification reaction times (RTs) reflected the increased perceptual difficulty of the morphed images. In Experiment 2, we investigated the effects of variations in the irrelevant dimension on judgments of faces with respect to a relevant dimension, using a Garner-type speeded classification task. RTs for expression classifications were strongly influenced by irrelevant identity information. In contrast, RTs for identity classifications were unaffected by irrelevant expression information, and this held even for stimuli in which identity was more difficult and slower to discriminate than expression. This suggests that differences in processing speed cannot account for the asymmetric relationship between identity and emotion perception. Theoretical accounts proposing independence of identity and emotion perception are discussed in the light of these findings.

This study investigated hemispheric asymmetries in repetition priming (Experiment 1) and associative priming (Experiment 2) in visual word recognition. Participants performed speeded lexical decisions for foveally presented target words that could be preceded by prime words presented to the left (LVF) or right (RVF) visual field. Experiment 1 demonstrated larger repetition priming in reaction times when prime words were presented to the RVF (left hemisphere). In contrast, no repetition priming was observed for pseudowords. Hemispheric asymmetries in word repetition priming may therefore reflect the superiority of the left hemisphere in activating lexical representations. Experiment 2 did not find any hemispheric asymmetries in associative priming. The results suggest that repetition priming and associative priming act on different levels in word recognition, for which different hemispheric asymmetries exist.

This study investigated the performance of left- (LBD) and right-brain-damaged (RBD) patients in recognizing personal names under different conditions of associative priming. Subjects performed speeded familiarity decisions for names of famous and unfamiliar persons. These target names were preceded by primes, either faces or names, which could be neutral, related (e.g. Gorbachev-Jelzin), or unrelated (e.g. Travolta-Carter). Overall impairments in name recognition were observed in both patient groups relative to controls but were more severe in LBD than in RBD patients. This suggests that, contrary to previous hypotheses, the recognition of personal names is more dependent on left hemisphere functioning. In controls and LBD patients, associative priming effects did not differ significantly between face and name primes. In RBD patients, however, associative priming from names was larger than priming from faces. This specificity of priming effects for names in RBD patients was tentatively related to their impairments in face recognition.