Non-linguistic Actions Research Articles

Perceptual invariance or orientation specificity in American Sign Language? Evidence from repetition priming for signs and gestures

Repetition priming has been successfully employed to examine stages of processing in a wide variety of cognitive domains including language, object recognition, and memory. This study uses a novel repetition priming paradigm in the context of a categorisation task to explore early stages in the processing of American Sign Language signs and self-grooming gestures. Specifically, we investigated the degree to which deaf signers’ and hearing nonsigners’ perception of these linguistic or nonlinguistic actions might be differentially robust to changes in perceptual viewpoint. We conjectured that to the extent that signers were accessing language-specific representations in their performance of the task, they might show more similar priming effects under different viewing conditions than hearing subjects. In essence, this would provide evidence for a visually based “lack of invariance” phenomenon. However, if the early stages of visual-action processing are similar for deaf and hearing subjects, then no such difference should be found. In both groups, we observed robust effects of viewpoint, indicating that repetition priming for identical prime–target pairs was greater than in cases of categorisation in which the prime and target varied in viewpoint. However, we found little evidence of group-related differences that could be interpreted as effects of perceptual invariance. These outcomes indicate that initial stages of sign and gesture recognition required for the categorisation of action types do not differ as a function of experience with a signed language. Instead, our data are consistent with and extend previously described visual-perceptual studies that have reported evidence for orientation-specific representations of human actions.

A human mirror neuron system for language: Perspectives from signed languages of the deaf

Language is proposed to have developed atop the human analog of the macaque mirror neuron system for action perception and production [Arbib M.A. 2005. From monkey-like action recognition to human language: An evolutionary framework for neurolinguistics (with commentaries and author’s response). Behavioral and Brain Sciences, 28, 105–167; Arbib M.A. (2008). From grasp to language: Embodied concepts and the challenge of abstraction. Journal de Physiologie Paris 102, 4–20]. Signed languages of the deaf are fully-expressive, natural human languages that are perceived visually and produced manually. We suggest that if a unitary mirror neuron system mediates the observation and production of both language and non-linguistic action, three prediction can be made: (1) damage to the human mirror neuron system should non-selectively disrupt both sign language and non-linguistic action processing; (2) within the domain of sign language, a given mirror neuron locus should mediate both perception and production; and (3) the action-based tuning curves of individual mirror neurons should support the highly circumscribed set of motions that form the “vocabulary of action” for signed languages. In this review we evaluate data from the sign language and mirror neuron literatures and find that these predictions are only partially upheld.

Neural correlates of human action observation in hearing and deaf subjects

Accumulating evidence has suggested the existence of a human action recognition system involving inferior frontal, parietal, and superior temporal regions that may participate in both the perception and execution of actions. However, little is known about the specificity of this system in response to different forms of human action. Here we present data from PET neuroimaging studies from passive viewing of three distinct action types, intransitive self-oriented actions (e.g., stretching, rubbing one’s eyes, etc.), transitive object-oriented actions (e.g., opening a door, lifting a cup to the lips to drink), and the abstract, symbolic actions-signs used in American Sign Language. Our results show that these different classes of human actions engage a frontal/parietal/STS human action recognition system in a highly similar fashion. However, the results indicate that this neural consistency across motion classes is true primarily for hearing subjects. Data from deaf signers shows a non-uniform response to different classes of human actions. As expected, deaf signers engaged left-hemisphere perisylvian language areas during the perception of signed language signs. Surprisingly, these subjects did not engage the expected frontal/parietal/STS circuitry during passive viewing of non-linguistic actions, but rather reliably activated middle–occipital temporal–ventral regions which are known to participate in the detection of human bodies, faces, and movements. Comparisons with data from hearing subjects establish statistically significant contributions of middle–occipital temporal–ventral during the processing of non-linguistic actions in deaf signers. These results suggest that during human motion processing, deaf individuals may engage specialized neural systems that allow for rapid, online differentiation of meaningful linguistic actions from non-linguistic human movements.

Neural processing of observed oro-facial movements reflects multiple action encoding strategies in the human brain

In this experiment, the oscillatory responses of the MEG were characterized during the observation of four viewing conditions: (a) observation of mouth movements, (b) observation of a non-biological motion stimulus (a mechanical aperture opening and shutting), (c) observation of object-directed mouth movements and (d) observation of speech-like mouth movements. Data were analyzed using synthetic aperture magnetometry (SAM) in three frequency bands, beta (15–35 Hz), gamma (35–70 Hz) and alpha/mu (8–15 Hz). Results showed that observations of biological motion resulted in beta desynchronization over lateral sensorimotor areas, while observations of non-biological motion resulted in a more medial desynchronization, an effect that may be related to the processing of a structured event sequence. Observation of linguistic movements resulted in less alpha/beta desynchronization in posterior brain regions in comparison to biological motion stimuli, suggesting that linguistically-relevant stimuli are processed with different neuronal systems than those recruited by normal action observation. We suggest that non-linguistic actions recruit dorsal systems while linguistic actions engage ventral processing systems. Object-directed movements showed the largest sensorimotor activations, suggesting that, as is the case for observations of hand movements, motoric processing is particularly sensitive to the viewing of goal-directed actions. Taken together, the results indicate that the brain utilizes multiple action encoding strategies, tailored to the function of the observed movement.

Action comprehension in aphasia: linguistic and non-linguistic deficits and their lesion correlates

We tested aphasic patients’ comprehension of actions to examine processing deficits in the linguistic and non-linguistic domains and their lesion correlates. Twenty-nine left-hemisphere injured patients and 18 age-matched control subjects matched pictured actions (with the objects missing) or their linguistic equivalents (printed sentences with the object missing) to one of two visually-presented pictures of objects. Aphasic patients performed poorly not only in the linguistic domain but also in the non-linguistic domain. A subset of the patients, largely consisting of severe and non-fluent aphasics, showed a greater deficit in the linguistic domain compared with the non-linguistic domain and across the patient group, deficits in the linguistic and non-linguistic domains were not tightly correlated. Poor performance in pantomime interpretation was associated with lesions in the inferior frontal, premotor and motor cortex, a portion of somatosensory cortex, and the caudate, while poor reading comprehension of actions was associated with lesions around the anterior superior temporal lobe, the anterior insula and the anterior portion of the inferior parietal lobe. Lesion size did not correlate with deficits. The lesion results for pantomime interpretation deficits demonstrate that lesions in the frontal component of the human analog of the “mirror neuron system” are associated with deficits in non-linguistic action understanding. For reading comprehension deficits, the lesion correlates are brain areas known to be involved in linguistic tasks including sentence processing and speech articulation; the parietal lesion site may also correspond to a subpart of the human mirror neuron system. These results indicate that brain areas important for the production of language and action are also recruited in their comprehension. Similar findings have been reported in electrophysiological and neuroimaging studies. Our findings now also lend neuropsychological support to an embodied view of brain organization for action processing.

The origins of grammar: Evidence from early language comprehension by Kathy Hirsh-Pasek and Roberta Michnick Golinkoff (review)

BOOK NOTICES 679 elsewhere. The focus throughout is on reconstruction of phonological and morphological systems rather than on individual roots or inflections. InCh. 1, 'Relationship and reconstruction' (1-18), realism in reconstruction is argued to include consistency with implicational universals, following the uniformitarian assumption that languages have not changed in kind within the time span accessible to reconstruction. This section includes a brief critique of long-range comparison, although no Nostratic reconstructions are considered in the book. Ch. 2, 'Principles of typology' (19-31), reviews the relevant typological background from a diachronic perspective. Ch. 3, 'Typology and reconstruction ' (32-43), addresses the relative value of absolute and statistical universals. Ch. 4, 'Indo-European phonology' (44-64) discusses the PlE vowel system and the laryngeal and glottalic theories, the typological support for which is clearly articulated. Jakobson's critique of traditional reconstructions of the ?G? consonant series may be seen as having launched the field under discussion, and with the development of the glottalic theory, this case remains the clearestapplication oftypology to reconstruction. This seems likely to continue with Nostratic/Eurasiatic , as similar arguments have been used by Allan Bomhard and others in evaluating alternative visions of Nostratic. Ch. 5 on morphology (65-73) discusses the applications of theories of grammaticalization and markedness to the murkier ground of PIE grammar; in Chs. 6 and 7 the approach is applied to nominal and verbal morphology respectively. The focus of Ch. 6 (74-88) is the case system, applying markedness and the case hierarchy to such topics as syncretism in IE case paradigms and the alignment of the PIE case system. Reconstructions of the IE nominative in -s as a former ergative marker and the -m accusative inflection as marking the object of an antipassive construction are found plausible but inconclusive , while the hypothesis of PIE as a stativeactive language appears more speculative. Ch. 7 (89-109) reconsiders the tense-aspect-mood and voice systems, connected as these are by links such as that between passive and stative perfect. The Hittite evidence suggests an alternative proto-system rather simpler than the Sanskrit/Greek-inspired model of earlier reconstructions. Not surprisingly, the discussion of grammatical features proves much less conclusive than that of phonological ones. One reason given is that application of typology in this domain is largely probabilistic , and the statistical strength of many (especially diachronic) universals of grammar has yet to be established . Such problems should not, however, deter historical linguists from pursuing S's line of argument further with respect to ?G? or other proto-languages . [Stephen Matthews, University of Hong Kong.] The origins of grammar: Evidence from early language comprehension. By Kathy Hirsh-Pasek and Roberta Michnick Golinkoff. Cambridge, MA: MIT Press, 1996. Pp. x, 230. The authors have packaged their research material with a comprehensive introductory overview and speculative conclusion. The inclusion of the nonresearch material may provide students with an understanding of the intellectual context in which research is conducted, and allows the book to reach a larger audience of non-linguistically-trained professionals in related fields of child development and psychology . Ch. 1 (1-10) provides a broad overview of the common questions and assumptions about first language acquisition. Ch. 2(11-52) reviews current language acquisition theories. Ch. 3 (53-72) briefly reviews problems in the methodology of previous studies and introduces the procedures which Hirsh-Pasek and Golinkoff use to alleviate the problems discussed. They address the widespread intuition that comprehension precedes production and the likelihood that experiments which claim to prove otherwise have some procedural problems , such as requiring the child to produce language in order to demonstrate comprehension. Some researchers have tried to solve this difficulty by asking children to perform a nonlinguistic action, but this introduces the problem ofdistinguishing noncomprehension from noncompliance. Drawing on research which shows that children are more likely to look at a scene which matches a given linguistic stimulus, H & M use an ingenious arrangement of videotapes and audiotapes which requires only the child's eye movement to signal comprehension, thus allowing them to investigate the comprehension of children who may not yet be speaking at all. The next three chapters present the details of their experiments. Ch. 4 (73...

Hand preference in gestures and signs in the deaf and hearing: Some notes on early evidence and theory

Research has shown that when persons with normal hearing accompany their speech with gestures, right-handers use more right-hand gestures, and left-handers use more left-hand gestures, although to a lesser extent ( D. Kimura, (1973a), (1973b), Neuropsychologia, 11, 45–50, 51–55.). Comparable differences have been found in deaf persons when signing, with the direction of hand dominance for signing in both right- and left-handers corresponding to that for nonlinguistic actions ( J. Vaid, D. Schemenauer, U. Bellugi, & H. Poizner, 1984, Hand dominance in a visual-gesture language, Paper presented at BABBLE, March, Niagara Falls, Ontario, Canada). In this paper, I recount early theories and observational data about hand dominance for gesture and signing, both in the hearing and the deaf. Several of these early theories and observations anticipate current work and also suggest new avenues for investigation.