Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 65 (1987), S. 649-657 
    ISSN: 1432-1106
    Keywords: Audio-initiated hand movement ; Cortical field potential ; Cerebellar hemispherectomy ; Monkey
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Monkeys were trained to respond to auditory stimulus by lifting a lever (audio-initiated hand movement), and field potentials were recorded. from various cortical areas with electrodes implanted on the surface and at a depth of 2.0–3.0mm, depending on the area. Tones of 500, 1000 and 2000 Hz were given to the monkey for about 500 or 10 ms, as auditory stimuli. In association with the movement, potentials of different configurations were recorded respectively in the primary auditory, auditory association, prefrontal, premotor, motor and somatosensory cortices. Initial surface-positive (s-P), depthnegative (d-N) potentials appeared in the primary auditory and auditory association cortices about 20 ms after the onset of the auditory stimulus, and they were often followed by s-N, d-P potentials. In the forelimb area of the motor cortex contralateral to the moving hand, s-N, d-P potentials appeared at a latency of about 100 ms. Following cerebellar hemispherectomy ipsilateral to the moving hand, the s-N, d-P potentials in the forelimb motor cortex were eliminated and reaction times prolonged. The same monkeys were also trained to perform a visuoinitiated movement, and results were compared with each other. Primary sensory and sensory association areas activated during such movements were certainly different, and the prefrontal association cortex appeared to participate much less predominantly in the audio- than in the visuo-initiated movement. Reaction times were generally longer and more variable for the audio- than for the visuo-initiated movement. Nevertheless the cerebello-thalamomotor cortical projection was found to be recruited in the same manner prior to both movements.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 70 (1988), S. 43-49 
    ISSN: 1432-1106
    Keywords: Audio-initiated hand movement ; Cortical field potential ; Motor learning ; Monkey
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Field potentials on the surface and at a depth of 2.0–3.0 mm in the cerebral cortex were recorded with chronically implanted electrodes in various areas of a monkey. The potentials associated with movements in response to auditory stimuli (audio-initiated hand movement) were observed during the learning process of the movement. The monkey had to lift a lever by wrist extension within the duration of the stimulus (tone of 1000 Hz) lasting for about 900, 700 or 500 ms depending on the stage of the learning process. On the first training day, potentials appeared in the primary auditory, auditory association, prefrontal and premotor cortices of a naive monkey. The potentials of the auditory association, prefrontal and premotor cortices became less marked on the next and following days. After a few weeks of training, the potential of the auditory association cortex started to increase again, while the monkey still lifted the lever randomly. When the potential of the auditory association cortex grew to a certain extent, the monkey began to respond to the stimulus with the movement, and potentials appeared in the motor cortex in response to the auditory stimulus. After this process, the potentials in the auditory association and motor cortices gradually increased with further training, and the movement became shorter and less variable in reaction time. The potential in the motor cortex was shown to be mediated by the neocerebellum and superficial thalamo-cortical projection. The changes of potentials associated with the learning processes of audio-initiated movements were respectively compared with those of the learning processes of the visuo-initiated movement, reported previously (Sasaki and Gemba 1982), and cortical and subcortical mechanisms related to the learning process were discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...