A quantitative study of the effect which a visual whole has upon its membral parts.

Zusammenfassung Ein Kreis kann in eine Ellipse mit betr?chtlicher Verschiedenheit der beiden Hauptachsen verwandelt werden, ehe er aufh?rt, anschaulieh ein Kreis zu sein. Liegt der Kreis inmitten einer kreisf?rmigen Anordnung von anderen figuren, so ist diese Schwelle noch weiter erh?ht, im Verh?ltnis 2: 3, wenn die umgebenden Figuren ebenfalls Kreise, deutlich weniger, wenn sie Ellipsen, und am wenigsten, wenn sie Quadrate sind.      

Categorical Perception of Face Actions: Their Role in Sign Language and in Communicative Facial Displays

Can face actions that carry significance within language be perceived categorically? We used continua produced by computational morphing of face-action images to explore this question in a controlled fashion. In Experiment 1 we showed that question-type-a syntactic distinction in British Sign Language (BSL)-can be perceived categorically, but only when it is also identified as a question marker. A few hearing non-signers were sensitive to this distinction; among those who used sign, late sign learners were no less sensitive than early sign users. A very similar facial-display continuum between 'surprise' and 'puzzlement' was perceived categorically by deaf and hearing participants, irrespective of their sign experience (Experiment 2). The categorical processing of facial displays can be demonstrated for sign, but may be grounded in universally perceived distinctions between communicative face actions. Moreover, the categorical perception of facial actions is not confined to the six universal facial expressions.     

The lateralization of lip-read sounds: a first look

Two tachistoscopic studies on the lateralization of lip-read still photographs in normal right handers are reported. In the first, subjects matched a still lip photograph with a heard speech sound. A clear right hemisphere (LVF) advantage emerged, despite the phonological requirements of this task. This pattern of laterality failed to interact with the type of response (same/different) or with the status of the heard phoneme; both consonant and vowel matching showed the same pattern of LVF advantage, despite the significantly greater difficulty of consonant than vowel matching in this particular task. In the second study subjects were required to speak the sound they saw being spoken by a centrally displayed face photograph. The displayed face was chimeric; that is, one side of the face was seen saying one sound, one side another. Here, a rather complex pattern of results ensued. For the speakers seen a clear expressor asymmetry emerged; speech sounds were judged more accurately when they issued from the right side of the speaker's face. However, in the LVF, and only the LFV, accuracy in reporting chimeric face sounds correlated with speed in learning to lip-read, suggesting that the LVF is systematically involved even when task demands (speaking the response, phonological analysis, small, more central displays) do not, at first sight, suggest that they should. Taken together, these studies suggest that the right hemisphere could support some aspects of the processing of seen speech in normally hearing, normally lateralized individuals.