Unitary Study on Evoked Activity of Callosal Neurons and Its Effect on Pyramidal Tract Cell Activity on Cats

Asanuma, Hiroshi; Okamoto, Kozi

doi:10.2170/jjphysiol.9.473

Cited by 56 publications

(16 citation statements)

References 7 publications

(5 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar kind of prolonged inhibition was also evoked by stimulating a symmetrical area in the contralateral cortex (Fig. 11), presumably by transcallosal activation, as previously shown by Asanuma & Okamoto (1959). Depth of stimulating electrode (mm) Fig.…”

Section: Inhibition In the Cortex 29supporting

confidence: 79%

“…Stronger evidence of true cortical inhibition came from subsequent studies of the effects of direct cortical shocks (Creutzfeldt, Baumgartner & Schoen, 1956), and of transcallosal (Creutzfeldt et al 1956; K. KRNJEVIC AND OTHERS Asanuma & Okamoto, 1959) and peripheral stimulation (Mountcastle, 1957;Mountcastle & Powell, 1959), as well as stimulation of the thalamus (Li, 1956), the caudate nucleus (Spehlmann, Creutzfeldt & Jung, 1960) and the pyramidal tract (Suzuki & Tukahara, 1963;. However, even these observations cannot be considered wholly conclusive, since there was little or no evidence that the inhibitory mechanism was operating directly on the observed cortical cells.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

An inhibitory process in the cerebral cortex

Krnjević¹,

Randić²,

Straughan³

1966

The Journal of Physiology

179

View full text Add to dashboard Cite

SUMMARY1. In cats, rabbits and monkeys, single cortical shocks can reduce the excitability of cortical neurones for 100-300 msec; the inhibitory effect is readily demonstrated, even in previously quiescent cells, against a background of activity evoked with small amounts of L-glutamate, released from an extracellular recording micropipette by iontophoresis.2. Other forms of cortical activity are also inhibited in a similar way by direct or indirect cortical stimulation; they include single unit discharges produced by iontophoretic applications of ACh or by a cathodal current, spontaneous discharges, and slow wave activity, both spontaneous and evoked.3. Most stimuli which elicit cortical activity also evoke some inhibition in the cortex, for instance, transcallosal volleys, and thalamic or peripheral shocks. In each case, a characteristic, prolonged depression is produced by single shocks.4. The most effective stimuli are direct cortical shocks, especially when applied within the cortex, below a depth of 0-6 mm; surface cathodal shocks are more effective than anodal shocks. These stimuli do not first excite the cells which are inhibited and they are not strong enough to cause appreciable local injury.5. Because of its long duration, the inhibition is often readily maintained by repetitive stimulation at frequencies of 5-7/sec. A cumulative effect leads to a further silent period after the end of stimulation; this increases with the strength, frequency and duration of the tetanus, so that after stimulation at 50-100/sec, the silent period may last for over 1 INHIBITION IN THE CORTEX 6. The inhibitory effect is often preceded and followed by phases of increased excitability; these may also show cumulative enhancement during repetitive stimulation, and a high frequency tetanus often leads to a short after-discharge, which is then followed by a long silent period, as above. Comparable changes take place in rabbits during spreading depression.7. The inhibitory effect of a direct shock can spread over an area covering 1 cm of cortical surface, affecting the cells through all cortical layers; but the spread is uneven in different directions, being particularly poor under most sulci.8. This type of inhibition can be elicited in all areas of the neocortex, and it is evident in kittens within a week of birth.9. Antidromic pyramidal stimulation is very much less effective in evoking inhibition of Betz cells, and other cortical neurones, than direct cortical stimulation; the inhibition by direct shocks is therefore not likely to be mediated through pyramidal excitation.

show abstract

Section: Inhibition In the Cortex 29supporting

confidence: 79%

Section: Introductionmentioning

confidence: 99%

An inhibitory process in the cerebral cortex

Krnjević¹,

Randić²,

Straughan³

1966

The Journal of Physiology

179

View full text Add to dashboard Cite

show abstract

“…In this respect, it is worth noting that symmetrical movements occur quite frequently during the first decade of child development, after which they disappear. Some authors have associated the disappearance of these mirror movements at the age of 10 with the progressive myelination of the corpus callosum (Asanuma & Okamoto, 1959;Asanuma & Okuda, 1962;Ferbert et al, 1992;Nass, 1985).…”

Section: Coordination Constraints During the Coordination Of Homologomentioning

confidence: 99%

Egocentric and Allocentric Constraints in the Expression of Patterns of Interlimb Coordination

Swinnen

Jardin

Meulenbroek

et al. 1997

Journal of Cognitive Neuroscience

167

110

View full text Add to dashboard Cite

Tasks that are easy when performed in isolation become difficult when performed simultaneously in the upper and/or lower limbs. This observation points to basic CNS constraints in the organization of patterns of interlimb coordination. The present studies provide evidence for the existence of two basic coordinative constraints whose effects may be additive under certain conditions. On one hand, the egocentric constraint denotes a general preference for moving the limbs toward or away from the longitudinal axis of the body in a symmetrical fashion and is of primary importance during the coordination of homologous limbs. On the other hand, the allocentric constraint refers to a general preference to move the limbs in the same direction in extrinsic space and pertains to the coordination of nonhomologous limbs (eg., various combinations of the upper and lower limbs). In the present context, constraints are considered as expressions of basic features of CNS operation that give way to preferred coordination patterns to which the system is naturally drawn or biased. The identification and description of these constraints is considered of critical importance to obtain a better understanding of the control of coordination patterns.

show abstract

“…From these results it seems that many cholinoceptive units are readily activated by transcallosal stimulation, but the excitation evoked by transcallosal volleys, whether orthodromic or antidromic (cf. Feng & Fan, 1957;Asanuma & Okamoto, 1959;Clare, Landau & Bishop, 1961) is distributed relatively evenly throughout the cortex, though possibly with a certain predilection for superficial as opposed to deep cells; hence there is no ground for believing that the callosal pathway is exclusively or even mainly cholinergic. In fact, it seems more likely that the cholinoceptive neurones received various kinds of relatively unspecific innervations, including transcallosal connexions (see also below).…”

Section: Characteristics Of Response To Achmentioning

confidence: 99%

“…They were usually discharging spontaneously in a fast and irregular manner (Martin & Branch, 1958) similar to projection activity. They often gave the characteristic repetitive responses to thalamic stimulation in the specific nuclei and they could be excited by transcallosal volleys (Feng.& Fan, 1957;Purpura & Girado, 1959;Asanuma & Okamoto, 1959;Patton & Amassian, 1960;Asanuma & Okuda, 1962). A good example of the behaviour of Betz cells is given in Text- fig.…”

Section: Excitation Of Betz Cells By Acetylcholinementioning

confidence: 99%