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J Kien

Publications and source records attributed to J Kien.

14 recordsLinked to original sources
PubMed1994

Is speech temporally segmented? Comparison with temporal segmentation in behavior.

Phrase durations in spoken German and Korean were examined for temporal segmentation like that in behavior. Lines of poetry, which may be regarded as semantic units equivalent to action units in behavior, were found to be temporally segmented but, unlike behavior, there is a significant effect of language/culture on segment length. The lengths of the pauses made between lines while reading poetry were used to define possible semantic segments in reading prose, retelling a story, free speech, and telephone messages. No temporal segmentation was found, each situation resulting in a different distribution of phrase durations. These results are discussed in terms of a possible evolution of language from the motor system.

Adult↗
PubMed1994

Temporal organisation of action in baboons: comparisons with the temporal segmentation in chimpanzee and human behaviour.

The durations of sequences of functionally related movements, or action units, were analysed in the baboons Papio hamadryas and Papio anubis. Action units are completed within a narrow time span or temporal segment as found previously in pongids and humans. Although the temporal segmentation is generally similar in the three species, baboons show several differences from both chimpanzees and humans. Firstly, their temporal segments are shorter and less variable and the different sorts of action units, such as hand-body contact or interactions with an object, show slight but significant differences in duration. Secondly, those action units that consist of movements occurring twice last almost twice as long as action units without repetitions. In contrast, in chimpanzees and humans, repetition of a set of movements compresses the first set so that the action unit duration does not increase. This is thought to be due to a form of presyntactical motor planning. Its absence in baboons shows that presyntactical motor planning is confined to those primates with language ability and so provides further support for a relationship between motor and language systems.

Animals↗
PubMed1992

Preparation and execution of movement: parallels between insect and mammalian motor systems.

1. The organization of the motor systems underlying locomotion in insects and mammals is surprisingly similar. There are also parallels between the insect motor system and the system underlying reaching and the occulomotor system in primates. 2. The movements generated by all these systems are planned or prepared before their execution and there is a partial separation of circuits for preparation and execution. 3. These circuits consist of multiple descending pathways interconnected to form overlapping loops which work co-operatively to determine the motor output. Thus, both insect and mammalian motor systems can be treated as parallel distributed (PDP) systems. 4. This enables a comparison of functional levels of processing in the different systems and also provides a basis for modelling motor systems with attractor neural networks.

Animals↗
PubMed1990

Neuronal activity during spontaneous walking--I. Starting and stopping.

1. The spontaneous release of walking in the locust is preceded by a preparatory phase consisting of "intentional" movements. This phase is absent when walking is evoked by sensory stimuli. 2. Some brain and suboesophageal (SOG) descending interneurons (DINs) become active before the preparatory phase. 3. During and after the preparatory phase new DINs are recruited predominantly from the SOG. 4. A large variety of activity patterns was recorded during spontaneous starts. These activity patterns are absent when walking is evoked by sensory stimulation. 5. Similarly complex and long lasting patterns were recorded during spontaneous stopping. 6. The data lead to refinement of the consensus model.

Animals↗
PubMed1990

Neuronal activity during spontaneous walking--II. Correlation with stepping.

1. During walking in the locust most active brain descending interneurons (DINs) and some from the suboesophageal ganglion (SOG) fire tonically but most SOG DINs show temporally patterned activity. 2. In over half the neurons the temporally patterned firing does not appear to correlate with the stepping cycle. 3. In the remainder, the coincidences with stepping appear to be with particular parts of the step cycle, that is with movement function, rather than with the movement itself. 4. These coincidences or "motor fields" range from the step functions of one leg to a concurrent set of step functions of 3-4 legs, to more than one such set of functions.

Animals↗
PubMed1984

A comparative study of neck muscle motor neurons in a cricket and a locust.

The gross morphology of the neck muscles of a cricket (Gryllus campestris) and their innervation are described and compared with a locust (Schistocerca gregaria). The motor neurons innervating the neck muscles were stained in crickets and locusts with cobalt chloride introduced via the nerve endings in the muscle. The two species show overall similarities, not only in position of the neck motor neurons in suboesophageal, prothoracic, and mesothoracic ganglia but also in motor neuron morphology. However, muscle 60 in the cricket is innervated by a unique motor neuron with its axon in prothoracic nerve 3, instead of sharing motor neurons in suboesophageal nerve 8 and mesothoracic nerve 1 with muscle 59, as in locust. Muscle 62 has the same attachments and innervation with similar motor neurons in cricket and locust but a different mechanical function in the two species. The findings are discussed with respect to possible segmental homologies and to the origins of the muscles as either dorso-ventral or longitudinal. As several muscles share the same motor neurons, we suggest that neck muscle function be described in terms of "behavioural units of action."

Animals↗
PubMed1979

Suboesophageal neurons involved in head movements and feeding in locusts.

The projections of nerves 6 and 7 of the locust suboesophageal ganglion (SOG) were stained by axonal filling with cobalt chloride. Nerve 6 contains two motoneurons which innervate neck muscles 50 and 51. Sensory neurons innervating hairs on the dorso-occipital region of the head also enter the ganglion through nerve 6 and terminate in a small bilateral plexus. The projections of the head hairs in nerve 6 do not overlap the arborizations of the motoneurons or the neurons of nerve 7, but lie in the same area as descending sensory neurons from wind-sensitive hairs of the front of the head. One branch of nerve 7 (7B) contains two fibres which innervate the salivary gland. These 'salivary' neurons (labelled SN1 and SN2) have their cell bodies in the ganglion. The second branch, 7A, contains sensory neurons from the submentum of the labium, which form four sensory plexuses, two dorsal and two ventral. The sensory plexuses from the submentum have specific regions of overlap with the salivary neurons and with the neck muscle motoneurons. We interpret these as indicating a flow of information from labial receptors signalling head and mouthpart movement to neurons involved in salivation and head movement. We further postulate that the anatomical separation of the various sensory plexuses is indicative of functional localization within the ganglion.

Animals↗