6 research outputs found

    Cross-race correlations in the abilities to match unfamiliar faces

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    The other-race effect in face identification has been documented widely in memory tasks, but it persists also in identity-matching tasks, in which memory contributions are minimized. Whereas this points to a perceptual locus for this effect, it remains unresolved whether matching performance with same- and other-race faces is driven by shared cognitive mechanisms. To examine this question, this study compared Arab and Caucasian observers' ability to match faces of their own race with their ability to match faces of another race using one-to-one (Experiment 1) and one-to-many (Experiment 2) identification tasks. Across both experiments, Arab and Caucasian observers demonstrated reliable other-race effects at a group level. At an individual level, substantial variation in accuracy was found, but performance with same-race and other-race faces correlated consistently and strongly. This indicates that the abilities to match same- and other-race faces share a common cognitive mechanism.Scopu

    Central pressor actions of aminopeptidase-resistant angiotensin II analogs: challenging the angiotensin III hypothesis

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    UNLABELLED: Intracerebroventricular administration of angiotensins causes pronounced pressor and dipsogenic responses. The suggestion that angiotensin III rather than angiotensin II is the active peptide in the brain spawned what we call The Angiotensin III. HYPOTHESIS: To test this hypothesis, 5 angiotensin II analogs containing zero or one position substitutions conferring resistance to aminopeptidases were administered intracerebroventricularly to determine their pressor and dipsogenic efficacies. Two aminopeptidase-resistant analogs caused significantly greater pressor responses than angiotensin II, whereas 3 analogs caused pressor responses similar to angiotensin II. Latency to cause a pressor response for 4 of the 5 aminopeptidase-resistant angiotensin II analogs was the same as for angiotensin II. There was no detectable formation of (125)I-angiotensin III from 1 of the intracerebroventricularly administered analogs, (125)I- N-Methyl-l-Asp(1)-angiotensin II, indicating its aminopeptidase resistance. Latency to drink also did not differ between the angiotensins. After the initial dipsogenic response, water was removed until 25 minutes after angiotensin administration to avoid interfering with the pressor response. The dipsogenic stimulus was sustained 25 minutes after intracerebroventricular injection of angiotensin II and its aminopeptidase-resistant analogs. Comparison of angiotensin III and angiotensin II showed equivalent pressor responses with similar latencies and durations. The latency to drink was similar for angiotensin III and angiotensin II. However, there was no dipsogenic response to angiotensin III 25 minutes after intracerebroventricular injection. These data do not support The Angiotensin III Hypothesis and suggest that conversion of exogenously applied angiotensin II to angiotensin III is not necessary to cause brain-mediated pressor or dipsogenic responses
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