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
Filter
  • 1990-1994  (2)
  • 1990  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 79 (1990), S. 83-91 
    ISSN: 1432-1106
    Keywords: Tonotopic organization ; Spatial sensitivity ; Inferior colliculus ; Auditory space representation ; Bat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The tonotopic organization and spatial sensitivity of 217 inferior collicular (IC) neurons of Eptesicus fuscus were studied under free field stimulation conditions. Acoustic stimuli were delivered from a loudspeaker placed 21 cm ahead of the bat to determine the best frequency (BF) and minimum threshold (MT) of isolated IC neurons. A BF stimulus was then delivered as the loudspeaker was moved horizontally across the frontal auditory space of the bat to locate the best azimuthal angle (BAZ) at which the neuron had its lowest MT. The stimulus was then raised 3 dB above the lowest MT to determine the horizontal extent of the auditory space within which a sound could elicit responses from the neuron. This was done by moving the loudspeaker laterally at every 5° or 10° until the neuron failed to respond. These measurements also allowed us to redetermine the BAZ at which the neuron fired maximal number of impulses. Electrodes were placed evenly across the whole IC surface and IC neurons were sampled as many as possible within each electrode penetration. Tonotopic organization and spatial sensitivity were examined among all 217 IC neurons as a whole as well as among IC neurons sequentially sampled within individual electrode penetrations. The whole population of 217 IC neurons is organized tonotopically along the dorsoventral axis of the IC. Thus, low frequency neurons are mostly located dorsally and high frequency neurons ventrally with median frequency neurons intervening in between. The BAZ of these 217 IC neurons tend to shift from lateral to medial portions of the contralateral frontal auditory space with increasing BF. Thus, the auditory space appears to have an orderly representation along the tonotopic axis of the IC. The lateral space is represented dorsally and the medial space ventrally. Nevertheless, tonotopic organization and spatial sensitivitty of sequentially isolated IC neurons within each electrode penetration may vary with the point of electrode penetration. This variation may be explained on the basis of the arrangement and thickness of each frequency lamina within the IC.
    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
    The European physical journal 335 (1990), S. 265-270 
    ISSN: 1434-601X
    Keywords: 21.60.Cs ; 23.20.Lv ; 27.60.+j
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Excited states in97Ag have been identified for the first time following the reactions46Ti(58Ni,α p 2n and64Zn(36Ar,p 2n. The population cross sections were 1.0(5) mb and 0.7(3) mb, respectively. Theγ-decay of the seniorityΝ=3 states below theI π=(17/2−) and (21/2+) isomers was investigated. In a search for short lived isomers half lives oft 1/2=5(2) ns and 2.5(5) ns were found in theN=50 isotones97Ag,I π=(17/2−) and/or (21/2+) and95Rh,I π=(21/2+). A new isomer was identified in97Pd,I π=17/2+ witht 1/2=2.3(5) ns. The implication of the three-proton hole spectrum in100Sn for the empirical residual interaction and shell model predictions is 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...