We analyzed the spontaneous prehensile activity of two infants living with their mothers in social groups, using videotapes taken once weekly from weeks 5 to 24. Prehensile activities were laterally symmetric. Unimanual activity predominated, although bimanual activity appeared at the same ages as unimanual activity. In most bimanual activity the two hands performed the same action, but complem...

Cells in macaque ventral premotor cortex (area F5c) respond to observation or production of specific hand-object interactions. Studies in humans associate the left inferior frontal gyrus, including putative F5 homolog pars opercularis, with observing hand actions. Are these responses related to the realized goal of a prehensile action or to the observation of dynamic hand movements? Rapid, even...

Three studies are reported, investigating changes in body engagement by 5to 6-month-old infants as they reach for ObJects in the environment. Infants are distinguished and compared based on their relative ability to maintain a sitting posture without any external body support. The first study demonstrates that manual reaching by sitter infants is coordinated with forward leamng of the trunk, wh...

The mobility of ray I was analysed in seventy-eight Early Permian to Late Cretaceous specimens of non-mammalian Synapsida and one extant mammal. In all non-mammaliamorph Synapsida investigated, ray I formed a digital arcade. The first phalanx was maximally extendable to the zero position in the metapodiophalangeal joint I. Metapodiale I was the functional equivalent to a basal phalanx of digits...

Using retrograde neuronal tracers, a study of the distribution of hypoglossal motor neurons innervating the tongue musculature was performed in the African pig-nosed frog, Hemisus marmoratum. This species is a radically divergent anuran amphibian with a prehensile tongue that can be aimed in three dimensions relative to the head. The results illustrate a unique rostrocaudal distribution of the ...

Object manipulation techniques in robotics can be categorized in two major groups including manipulation with and without grasp. The aim of this paper is to develop an object manipulation method where in addition to being grasp-less, the manipulation task is done in a passive approach. In this method, linear and angular positions of the object are changed and its manipulation path is controlled...

Ideomotor apraxia (IM) is a disorder of skilled action characterized by spatiotemporal errors in pantomiming object use and in using objects. Recent evidence suggests that at least some patients with IM may exhibit particular deficits in forming hand configurations appropriate for object use. Sirigu et al. [Cortex 31 (1995) 41] reported an apraxic who positioned her hand inappropriately when at...

Abstract The prehensile-tailed skink Corucia zebrata is endemic to the Solomon Islands. It most traded reptile from country. During 2000–2019, CITES reported legal export of 10,567 individuals. Although level this trade well documented, impacts on skink's survival in its native range are comparatively unknown. January–May 2020, we surveyed 146 people 12 islands collect information habitats pref...