Abstract：
:Recognition of sound patterns must be largely independent of level and of masking or jamming background sounds. Auditory patterns of relevance in numerous environmental sounds, species-specific vocalizations and speech are frequency modulations (FM). Level-dependent activation of the human auditory cortex (AC) in response to a large set of upward and downward FM tones was studied with low-noise (48 dB) functional magnetic resonance imaging at 3 Tesla. Separate analysis in four territories of AC was performed in each individual brain using a combination of anatomical landmarks and spatial activation criteria for their distinction. Activation of territory T1b (including primary AC) showed the most robust level dependence over the large range of 48-102 dB in terms of activated volume and blood oxygen level dependent contrast (BOLD) signal intensity. The left nonprimary territory T2 also showed a good correlation of level with activated volume but, in contrast to T1b, not with BOLD signal intensity. These findings are compatible with level coding mechanisms observed in animal AC. A systematic increase of activation with level was not observed for T1a (anterior of Heschl's gyrus) and T3 (on the planum temporale). Thus these areas might not be specifically involved in processing of the overall intensity of FM. The rostral territory T1a of the left hemisphere exhibited highest activation when the FM sound level fell 12 dB below scanner noise. This supports the previously suggested special involvement of this territory in foreground-background decomposition tasks. Overall, AC of the left hemisphere showed a stronger level-dependence of signal intensity and activated volume than the right hemisphere. But any side differences of signal intensity at given levels were lateralized to right AC. This might point to an involvement of the right hemisphere in more specific aspects of FM processing than level coding.
journal_name
J Neurophysioljournal_title
Journal of neurophysiologyauthors
Brechmann A,Baumgart F,Scheich Hdoi
10.1152/jn.00187.2001subject
Has Abstractpub_date
2002-01-01 00:00:00pages
423-33issue
1eissn
0022-3077issn
1522-1598journal_volume
87pub_type
临床试验,杂志文章abstract：:Several models exist for explaining primary visual cortex (V1) orientation tuning. The modified feedforward model (MFM) and the recurrent model (RM) are major examples. We have implemented these two models, at the same level of detail, alongside a few newer variations, and thoroughly compared their receptive-field str...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00015.2005
更新日期：2006-07-01 00:00:00
abstract：:The purpose of this study was to examine changes in motor unit activity in the biceps brachii muscle after an initial (Bout 1) and repeated (Bout 2) session of eccentric exercise separated by 1 wk. Eight subjects (aged 22 ± 2 yr) participated in experimental assessments of neuromuscular function obtained before, immed...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00854.2010
更新日期：2011-03-01 00:00:00
abstract：:Paired-pulse transcranial magnetic stimulation (TMS) and peripheral stimulation combined with TMS can be used to study cortical interneuronal circuitry. By combining these procedures with concurrent transcranial alternating current stimulation (tACS), Guerra and colleagues recently showed that different cortical inter...
journal_title：Journal of neurophysiology
pub_type： 杂志文章,评审
doi：10.1152/jn.00060.2017
更新日期：2017-06-01 00:00:00
abstract：:The vestibular system plays a critical role in detection of head movements and is essential for normal postural control. Because of their anatomical proximity to the cochlea, the otolith organs are selectively exposed to sound pressure and are at risk for noise overstimulation. Clinical reports suggest a link between ...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00668.2017
更新日期：2018-02-01 00:00:00
abstract：:We present a cell-based model of the Limulus lateral eye that computes the eye's input to the brain in response to any specified scene. Based on the results of extensive physiological studies, the model simulates the optical sampling of visual space by the array of retinal receptors (ommatidia), the transduction of li...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1998.80.4.1800
更新日期：1998-10-01 00:00:00
abstract：:1. The electrophysiological and pharmacological properties of slow afterpotentials in large layer V neurons from cat sensorimotor cortex were studied in an in vitro slice preparation using intracellular recording and single-microelectrode voltage clamp. These properties were used to assess the role of afterpotential m...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1988.59.2.450
更新日期：1988-02-01 00:00:00
abstract：:1. The responses of single neurons in the primary somatosensory cortex of the cat to brief air-pulse stimuli were quantitatively examined. These controlled natural stimuli activated almost exclusively rapidly adapting hair units which, on systematic movement of the stimulus through the receptive field, gave unit-respo...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1979.42.4.1061
更新日期：1979-07-01 00:00:00
abstract：:Long-term synaptic depression (LTD) of cerebellar parallel fiber-Purkinje cell synapses is a form of use-dependent synaptic plasticity that may be studied in cell culture. One form of LTD is induced postsynaptically through an mGlu1/Ca influx/protein kinase Cα (PKCα) cascade, and its initial expression requires phosph...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00824.2011
更新日期：2012-01-01 00:00:00
abstract：:The ability to adjust the amplitude of gaze shifts in response to persistent visual errors ("gaze adaptation") has been investigated primarily by introducing visual errors at the end of saccades produced by head-restrained primates. Very little is known about the behavior and neural mechanisms underlying gaze adaptati...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.90735.2008
更新日期：2009-01-01 00:00:00
abstract：:Limb movement-related neurons in the cerebellar nuclei (CN) typically produce bursts of discharge in association with movement. Consequently, given the inhibitory nature of the Purkinje cell (PC) projection to CN, it is puzzling that only a minority of movement-related PCs pause; the majority burst. Some of the moveme...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00603.2004
更新日期：2005-01-01 00:00:00
abstract：:1. The inhibitory response of exogenously applied glycine was investigated in freshly dissociated rat nucleus tractus solitarii neurons under whole cell configuration using new perforated patch-clamp technique termed "gramicidin perforated patch technique," which maintains intact intracellular Cl- concentrations. 2. U...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1994.72.3.1103
更新日期：1994-09-01 00:00:00
abstract：:Regularly discharging vestibular-nerve afferents innervating the semicircular canals were recorded extracellularly in anesthetized chinchillas undergoing high-frequency, high-velocity sinusoidal rotations. In the range from 2 to 20 Hz, with peak velocities of 151 degrees/s at 6 Hz and 52 degrees/s at 20 Hz, 67/70 (96%...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1999.82.4.2000
更新日期：1999-10-01 00:00:00
abstract：:Over the past 3 decades, various algorithms used to decompose the electromyographic (EMG) signal into its constituent motor unit action potentials (MUAPs) have been reported. All are limited to decomposing EMG signals from isometric contraction. In this report, we describe a successful approach to decomposing the surf...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00555.2014
更新日期：2015-03-15 00:00:00
abstract：:The purpose of the present study was to determine whether retinal activity can support long-term changes in synaptic strength in the developing dorsal lateral geniculate nucleus (LGN) of thalamus. To test for this we made use of a rodent in vitro explant preparation in which retinal afferents and the intrinsic circuit...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.90618.2008
更新日期：2009-12-01 00:00:00
abstract：:Cellular mechanisms underlying defense reactions induced by noxious heat and acids were studied in frogs (Rana pipiens) by measuring whole cell membrane currents in cultured dorsal root ganglion (DRG) neurons. Seventy-eight of 82 DRG neurons exposed to 3-s ramps of increasing temperature to 48 degrees C exhibited an i...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.2002.88.4.1843
更新日期：2002-10-01 00:00:00
abstract：:Neuron loss, axon sprouting, and the formation of new synaptic circuits have been hypothesized to contribute to seizures in temporal lobe epilepsy (TLE). Using the kainate-treated rat, we examined how alterations in the density of CA1 pyramidal cells and interneurons, and subsequent sprouting of CA1 pyramidal cell axo...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.2001.85.1.1
更新日期：2001-01-01 00:00:00
abstract：:The experiments described in this report were designed to determine the contribution of vestibulospinal neurons (VSNs) in Deiters' nucleus and of reticulospinal neurons (RSNs) in the medullary reticular formation to the modifications of the walking pattern that are associated with locomotion on an inclined plane. Neur...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.2000.84.5.2257
更新日期：2000-11-01 00:00:00
abstract：:The excitatory and inhibitory conductances driving the light-evoked currents (LECs) of cat and ferret ON- and OFF-center X ganglion cells were examined in sliced and isolated retina preparations using center spot stimulation in tetrodotoxin (TTX)-containing Ringer. ON-center X ganglion cells showed an increase in an e...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1998.80.6.2975
更新日期：1998-12-01 00:00:00
abstract：:1. Brain ischemia causes excess release and accumulation of glutamate that binds to postsynaptic receptors. This opens ionotropic channels that mediate neuronal depolarization and ionic fluxes that can lead to neuronal death. 2. The CA1 pyramidal cell region of the hippocampus is particularly susceptible to this neuro...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1996.76.4.2707
更新日期：1996-10-01 00:00:00
abstract：:Behavioral and physiological characteristics of standing were studied in nontrained spinal cats and in spinal cats that received daily stand training of the hindlimbs for 12 wk. Training consisted of assisting the cats to stand with full weight support either on both hindlimbs or on one hindlimb (30 min/day, 5 days/wk...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1998.80.1.83
更新日期：1998-07-01 00:00:00
abstract：:1. We investigated gamma-aminobutyric acid (GABA) receptors using thin slice patch-clamp techniques in the swellings along axons of posterior pituitary nerve terminals. 2. Activation of the nerve terminal GABAA receptor induced a mean conductance change of 1.5 nS. Normalizing to area gave a mean conductance density of...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1995.73.3.1135
更新日期：1995-03-01 00:00:00
abstract：:Support-surface movements are commonly used to examine balance control. Subjects typically receive a series of identical or randomly interspersed multidirectional balance perturbations and the atypical "first trial reaction" (evoked by the first perturbation) is often excluded from further analysis. However, this proc...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.90945.2008
更新日期：2009-06-01 00:00:00
abstract：:Individuals with chronic spinal cord injury (SCI) often demonstrate multijoint reflex activity that is clinically classified as an extensor spasm. These responses are commonly observed in conjunction with an imposed extension movement of the hips, such as movement from a sit to a supine position. Coincidentally, affer...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00677.2003
更新日期：2004-08-01 00:00:00
abstract：:The complementary DNA encoding gustatory cyclic nucleotide--gated ion channel (or gustCNG channel) cloned from rat tongue epithelial tissue was expressed in Xenopus oocytes, and its electrophysiological characteristics were investigated using tight-seal patch-clamp recordings of single and macroscopic channel currents...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.2001.85.6.2335
更新日期：2001-06-01 00:00:00
abstract：:Mechanoelectric transducer (MET) channels, located near stereocilia tips, are opened by deflecting the hair bundle of sensory hair cells. Defects in this process result in deafness. Despite this critical function, the molecular identity of MET channels remains a mystery. Inherent channel properties, particularly those...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.01178.2011
更新日期：2012-05-01 00:00:00
abstract：:Studies on animals have shown that noise-induced hearing loss is followed by an increase of spontaneous firing at several stages of the central auditory system. This central hyperactivity has been suggested to underpin the perception of tinnitus. It was shown that decreasing cochlear activity can abolish the noise-ind...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00580.2014
更新日期：2015-01-01 00:00:00
abstract：:Adaptive processes are crucial in maintaining the accuracy of body movements and rely on error storage and processing mechanisms. Although classically studied with adaptation paradigms, evidence of these ongoing error-correction mechanisms should also be detectable in other movements. Despite this connection, current ...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00779.2013
更新日期：2014-05-01 00:00:00
abstract：:During auditory stimulation with several frequency components, distortion products (DPs) are generated as byproduct of nonlinear cochlear amplification. After generated, DP energy is reemitted into the ear channel where it can be measured as DP otoacoustic emission (DPOAE), and it also induces an excitatory response a...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.90805.2008
更新日期：2009-03-01 00:00:00
abstract：:Cortical activity contributes significantly to the high variability of sensory responses of interconnected pyramidal neurons, which has crucial implications for sensory coding. Yet, largely because of technical limitations of in vivo intracellular recordings, the coupling of a pyramidal neuron's synaptic inputs to the...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00398.2017
更新日期：2017-12-01 00:00:00
abstract：:Transcranial magnetic stimulation (TMS) is increasingly used to modify brain activity noninvasively and to study brain-behavior relations. However, results can be variable and the conditions that affect the functional efficacy of TMS remain unclear. Here we show that on-line TMS can either facilitate or suppress perce...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.01392.2007
更新日期：2008-05-01 00:00:00
