Neuronal response patterns in the cochlear nuclei: effects of vowel position on discharge rate

1974 ◽  
Vol 55 (S1) ◽  
pp. S85-S86 ◽  
Author(s):  
A. L. Rupert ◽  
D. M. Caspary ◽  
G. Moushegian
Keyword(s):  
Discharge Rate ◽  
Neuronal Response ◽  
Response Patterns ◽  
Cochlear Nuclei

BRAIN-STEM NEURONAL RESPONSE PATTERNS TO MONAURAL AND BINAURAL TONES

1964 ◽  
Vol 27 (6) ◽  
pp. 1174-1191 ◽  
Author(s):  
George Moushegian ◽  
Allen Rupert ◽  
Milton A. Whitcomb
Keyword(s):  
Brain Stem ◽  
Neuronal Response ◽  
Response Patterns

Beta-contributions to fusimotor action in triceps surae muscles of decerebrated cats

1987 ◽  
Vol 57 (2) ◽  
pp. 574-595 ◽  
Author(s):  
S. E. Grill ◽  
W. Z. Rymer
Keyword(s):  
Muscle Force ◽  
Discharge Rate ◽  
Muscle Spindles ◽  
Triceps Surae ◽  
Medial Gastrocnemius ◽  
Gamma Activity ◽  
Response Patterns ◽  
Two Measures ◽  
Triceps Surae Muscles ◽  
Stimulation Of

The discharge of spindle afferents from medial gastrocnemius and soleus muscles was recorded in the decerebrated cat preparation, under isometric conditions and during ramp and hold stretches. Motor output was varied systematically by manual stimulation of the contralateral hindlimb. Twenty-six of 34 afferents showed response patterns consistent with enhancement of dynamic and/or static fusimotor input with increasing muscle force. To establish whether force-related fusimotor effects were mediated at least partly by beta-input, beta-innervation to these same spindles was sought, using a ventral root stimulation protocol. Twenty-three of the 34 afferents were shown to receive beta-innervation, which was most often static in type. For two measures of fusimotor action, the slope of the afferent dynamic rate-length relation and the discharge rate measured during the last portion of ramp stretch, significant increases in the measure, which paralleled increases in muscle force, made it statistically more likely that the afferent received beta-innervation. Our measures did not successfully predict the type of beta-input (beta-static or beta-dynamic). Procaine block of gamma-fibers produced substantial reductions in fusimotor effect in seven spindle afferents (although modest residual fusimotor effects were detectable for 3/7 afferents). The severity of these reductions indicates that beta-action probably requires concurrent gamma-input to the spindle in order to be effective. In support of this possibility, the fusimotor effects of electrical stimulation of single beta-fibers were greatly reduced for five out of six afferents during procaine block of gamma-fibers, compared with the beta-effects recorded when modest levels of spontaneous gamma-activity were present. We conclude that beta-innervation to muscle spindles of triceps surae is common and that this innervation exerts significant fusimotor effects. It appears likely that beta-motoneurons are able to produce both static and dynamic effects above extrafusal threshold, but that the actions require on-going gamma-activity in order to be effective.

Response Characteristics of Cochlear Nucleus Neurons to Vowel Sounds

1977 ◽  
Vol 86 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Allen L. Rupert ◽  
Donald M. Caspary ◽  
George Moushegian
Keyword(s):  
Cochlear Nucleus ◽  
Discharge Rate ◽  
Neuronal Responses ◽  
Response Characteristics ◽  
Cochlear Nuclei ◽  
Kangaroo Rat ◽  
Complete Basis ◽  
Pure Tones ◽  
Neural Discharge ◽  
Tonal Stimuli

Most studies in auditory neurophysiology have utilized tonal stimuli to determine the coding properties of neurons in the cochlear nuclei. In this investigation of the kangaroo rat, cochlear nuclei, neuronal responses to vowel sounds, as well as tones, were studied. The vowel sounds, each about 40 msec in duration were: [a], [i], [I], [ε], [o], [u], [Formula: see text] [æ], and [ṛ]. Five were linked together to form a 200 msec stimulus and various combinations of five vowel sounds provided us with 18 different stimuli. The results show that neurons in the cochlear nuclei are remarkably sensitive and selective to vowel sounds. Furthermore, the responses of these neurons to pure tones do not provide a complete basis to predict the types of responses to the vowel sounds. More significant is the finding that the neural discharge rate and pattern of discharge to a particular vowel may depend on where the vowel appears in the stimulus and what other vowel precedes it. This vowel positional effect is not the same for every neuron. We have called this phenomenon a neural “set.”

scholarly journals Delta activity encodes taste information in the human brain

2018 ◽  
Author(s):  
Raphael Wallroth ◽  
Kathrin Ohla
Keyword(s):  
Human Brain ◽  
Neuronal Response ◽  
Pattern Discrimination ◽  
Nutrient Sensing ◽  
Response Patterns ◽  
Gustatory System ◽  
Rapid Responses ◽  
Delta Activity ◽  
Taste Discrimination ◽  
Eeg Recordings

The categorization of food via sensing nutrients or toxins is crucial to the survival of any organism. On ingestion, rapid responses within the gustatory system are required to identify the oral stimulus to guide immediate behaviour (swallowing or expulsion). The way in which the human brain accomplishes this task has so far remained unclear. Using multivariate analysis of 64-channel scalp EEG recordings obtained from 16 volunteers during tasting salty, sweet, sour, or bitter solutions, we found that activity in the delta-frequency range (1-4 Hz; delta power and phase) has information about taste identity in the human brain, with discriminable response patterns at the single-trial level within 130 ms of tasting. Importantly, the latencies of these response patterns predicted the point in time at which participants indicated detection of a taste by pressing a button. Furthermore, taste pattern discrimination was independent of motor-related activation and other taste features such as intensity and valence. On comparison with our previous findings from a passive (delayed) taste-discrimination task (Crouzet et al., 2015), taste-specific neural representations emerged earlier during this active (speeded) taste-detection task, suggesting a goal-dependent flexibility in gustatory response coding. Together, these findings provide the first evidence of a role of delta activity in taste-information coding in humans. Crucially, these neuronal response patterns can be linked to the speed of simple gustatory perceptual decisions, a vital performance index of nutrient sensing.

GABA actions within the caudal cochlear nucleus of developing kittens

1990 ◽  
Vol 64 (3) ◽  
pp. 961-977 ◽  
Author(s):  
E. J. Walsh ◽  
J. McGee ◽  
J. L. Fitzakerley
Keyword(s):  
Cochlear Nucleus ◽  
Discharge Rate ◽  
Neuronal Response ◽  
Acoustic Stimulation ◽  
Spontaneous Discharge ◽  
Maximal Effect ◽  
Dependent Manner ◽  
Response Curves ◽  
Discharge Rates ◽  
Dose Dependent

1. The effects of gamma-aminobutyric acid (GABA), microionophoretically applied onto neurons within the dorsal and posteroventral divisions (i.e., caudal regions) of the cochlear nucleus (CN), were studied during postnatal development in kittens with the use of extracellular recording techniques. Approximately 80% of all neurons encountered within the caudal CN responded to exogenously applied GABA regardless of neuronal response type or postnatal age. 2. GABA reduced acoustically evoked as well as spontaneous discharge rates in a dose-dependent manner at all ages studied, and generally abolished discharge activity at sufficiently high doses (i.e., ejection currents). Dose-response curves generated during acoustic stimulation by varying GABA ejection current were sigmoidal at all ages studied, and the range of slopes relating discharge rate to applied currents increased during the first 10 postnatal days. 3. Neural thresholds to acoustic stimuli were elevated, and slopes of discharge-rate-versus-sound-pressure-level curves were depressed regardless of age when GABA was microionophoresed onto CN neurons. 4. GABA's capacity to reduce spontaneous or acoustically evoked discharge rates was a voltage-dependent phenomenon directly related to control discharge rates (i.e., efficacy was high when discharge rates were high) for neurons recorded from both immature and mature animals. 5. A small set of neurons recorded from animals younger than 2 wk exhibited prolonged GABA "activation" and "deactivation" times (i.e., times required to achieve 90% of the maximal effect evoked by GABA and to recover from that effect, respectively) and may represent a group of actively differentiating units. 6. Bicuculline microionophoresis effectively blocked the actions of exogenously applied GABA and endogenous GABA, which, presumably, was synaptically released as a result of acoustic stimulation. The actions of bicuculline were dose dependent in animals ranging in age from 2 postnatal days to adulthood. These results suggest that recognition sites for GABA and bicuculline and the ionophore associated with the GABA receptor are present and functionally coupled in the caudal CN before the developmental period during which the full complement of inhibitory projections form synaptic contacts with these cells.

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