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 21 (1974), S. 403-418 
    ISSN: 1432-1106
    Keywords: Lateral reticular nucleus ; Antidromic activation ; Field potentials ; Membrane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Antidromically activated intracellular and field potentials in the lateral reticular nucleus (LRN) of cat were recorded with microelectrode following stimulation of the inferior cerebellar peduncle. LRN antidromic field potentials were well synchronized and relatively short duration negative waves. These potentials were observed only when the recording electrode was within the nucleus. No reversal of the negative potentials was detected outside of the nucleus. Intracellular analysis revealed that antidromic firing of the LRN neuron is composed of M-IS-SD spikes. The IS-SD spike duration was short and sometimes followed by an afterpotential sequence of depolarization and hyperpolarization. Effects of depolarizing and hyperpolarizing currents, injected through the recording electrode, on the antidromic spike, membrane resistance and firing pattern were studied. Findings demonstrated that LRN cells are capable of high frequency firing with little accomodation. The membrane also displayed rectification properties. These results imply that LRN neurons are highly sensitive to depolarization signals and possess characteristics for providing background depolarization and tonic activation of their target neurons.
    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 17 (1973), S. 463-476 
    ISSN: 1432-1106
    Keywords: Septum ; Hippocampus ; Function ; Electrophysiology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The septum and dorsal hippocampus were exposed in rats by the ablation of the overlying cortex and corpus callosum. The hippocampal efferent system, fornix and fimbria, were stimulated with either single or paired shocks and field potentials, extra- and intra-cellular unitary potentials were recorded in the lateral septal nucleus. 2. The double-shock pairing within the same hippocampal system resulted in facilitation of the monosynaptic test field response. 3. Pairing across systems resulted in long-term suppressions of the mono-synaptic test field response. 4. IPSPs and lack of convergence of excitatory input are responsible for the long-term suppression. 5. It is suggested that the IPSPs are mediated via interneurons, and that some of which at least are activated recurrently. 6. Hippocampal stimulation suppresses the amygdaloid evoked field response for very long periods, often beyond 1000 msec.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 17 (1973), S. 447-462 
    ISSN: 1432-1106
    Keywords: Septum ; Hippocampus ; Topography ; Fimbria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The hippocampal input to the septal region was studied, in rats, by electrophysiological methods. The major observations were: 1. the hippocampal fibers are excitatory with respect to their target cells in the lateral septal nucleus (LSN); 2. the distribution of the subcallosal fornix is restricted to the dorsomedial regions of the LSN; 3. the fimbria contains fibers terminating throughout the dorsal aspect of the ipsilateral and contralateral septum; 4. there is an extensive overlapping in the distribution of the ipsi-and contra-lateral fimbria components with convergence upon single septal cells frequently seen; 5. the posterior part of hippocampal region CA1 contributes fibers to the fimbria as well as to the fornix.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 21 (1974), S. 419-432 
    ISSN: 1432-1106
    Keywords: LRN ; Synaptic inputs ; Deep cerebellar nuclei ; Red nucleus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intracellular potentials of lateral reticular nucleus (LRN) cells of the cat were recorded following stimulation of the spinal cord (SP), red nucleus (RN), cerebral peduncle (CP), nucleus interpositus (IP) and nucleus fastigius (Fg). Single shock stimulation of all of the above sites induced monosynaptic and polysynaptic EPSPs in the LRN cells. Disynaptic and polysynaptic IPSPs were also observed especially following Sp stimulation. Both Sp induced EPSPs and IPSPS could be reversed by intracellular current injection indicating that they are generated at or near the soma of the LRN cell. Collision experiments between Sp and IP induced EPSPs, and IP-Fg induced EPSPs showed that independent excitatory pathways exist from the Sp and the deep cerebellar nuclei to the LRN. Collision experiments between RN and IP induced EPSPs and their respective time courses showed that disynaptically IP induced EPSPs in LRN cells are mediated through the red nucleus. Findings indicate the existence of 1. a multiple convergence of spinal, suprasegmental and cerebellar synaptic inputs to the LRN and 2. direct (LRN-IP-LRN) or indirect (LRN-IP-RN-LRN) excitatory feed back loops between the cerebellar nuclei and this precerebellar nucleus.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Rats were undernourished postnatally from birth through 20 days of age. They were subsequently tested for susceptibility to motor seizures kindled in hippocampus in adulthood. Compared to littermate control animals the postnatally undernourished rats were more susceptible to the kindling treatment. We conclude that early postnatal undernourishment has a permanent effect on susceptibility of the hippocampus to electrically-induced seizures.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 31 (1975), S. 809-810 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The electrophysiological characteristics of the medical forebrain bundle (MFB) projections to the nucleus of the diagonal band of Broca (nDBB) were studied in acutely prepared cats. MFB stimulation evoked field potentials which consisted of a large negative wave followed by a shallow positivity. Extracellular unitary discharges appeared out of the negativity. In addition, intracellularly recorded EPSPs showed no significant shift in the latency to onset with changes in stimulus intensity. These observations indicate that at least some of the MFB projections to the nDBB are excitatory with respect to their target cells.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1573-6792
    Keywords: Spatial orientation ; Topographic mapping ; Temporal lobe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The results from this spatial orientation, or cue priming, investigation found that targets presented to the contralateral visual fields differentially activated the temporal zones. For instance, stimulation within the right visual field lead to activation of the left temporal zones, as indexed by the relative prominence of the association negativity, N2. The converse was true for left visual field stimulation. For both visual field stimulation, the N2 component also showed an occipital and parietal distribution. The P300 component, which is presumed to be modulated by medial temporal lobe structures, showed the classic centroparietal distribution. Somewhat surprisingly, differences between the primed (e.g.,‘facilitated’) and ‘normal’ conditions for the N2 component appeared restricted to the occipital zones. Here, the significant variable was the N2 peak latency. Hence, the priming cue appears to quicken the maximal development of the N2 processing component, preferentially over the occipital cortex, and this may partially explain the faster reaction times in the ‘facilitated’ conditions for both visual fields.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Brain topography 9 (1997), S. 283-293 
    ISSN: 1573-6792
    Keywords: Brain mapping ; Visual attention ; P150 ; N200 ; P250 ; P450
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This investigation explored developmental changes in passive and effortful components of ERPs associated with a visual attention task in children, adolescents, and adults. The task was a ‘go-go’ version of a continuous performance task, coupled with a passive attending phase in which the subjects merely watched the stimuli of the task. The three age groups featured a constellation of ERP components that shared the same general morphological appearance and distribution, but differences were seen with respect to latencies and amplitudes. Consistent with other studies, there was an inverse relationship with respect to age and peak latencies of the major passive and effortful components. With respect to peak amplitudes, however, the most impressive changes with age were observed in the passive processing components. For example, the P150 and P250 components presented greater amplitudes in children, whereas the N200 component presented its greatest amplitude in adults. While passive in the sense that their appearances were independent of the ‘decision-making’ process, these components were found to be upwardly adjustable by effort. The late positive component was found to be a combination of a passive P350 and an effortful P450.The P350 component was judged to be largely passive in character as it was well developed in subjects of all age groups when passively attending to the visual stimuli. There was no marked amplitude difference between the child and adult P450 components, but the components peaked in amplitude later in the children. Finally, the children's ERPs featured a distinct frontal negativity (FN) that was present in the Passive phase, but greatly enhanced during the Effortful phase. This study, as have many others, showed that there are reliable developmental changes in the components of visual ERPs. Therefore, the characteristics of the various components of cognitive ERPs may be effective markers of neurodevelopmental status, especially of those neuronal systems vital to attentional processing and effort regulation.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Metabolic brain disease 1 (1986), S. 293-293 
    ISSN: 1573-7365
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    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...