Whisker Vibration Information Carried by Rat Barrel Cortex Neurons

Arabzadeh, Ehsan; Panzeri, Stefano; Diamond, Mathew E.

doi:10.1523/jneurosci.1389-04.2004

Cited by 137 publications

(143 citation statements)

References 46 publications

Supporting

Mentioning

131

Contrasting

Order By: Relevance

“…In our experiments the duration of the pulse was fixed, so velocity and speed covary with amplitude: Amplitude noise also may be considered noise in velocity (or its absolute value, speed). Because of the robust encoding of stimulus velocity (15,16) and the weaker encoding of pure amplitude (22), our view is that velocity (speed) is the stimulus feature through which noise exerts its effects.…”

Section: Discussionmentioning

confidence: 99%

“…Suppose that neurons in barrel cortex have sigmoidal input-output functions, where input is the strength of the sensory event (amplitude or speed of whisker movement), and output is spiking probability (figure 2b in ref. 16). In a noisy-amplitude train, some deflections would fall above and others below the threshold; the neurons would effectively "skip" some deflections, and the intrinsic resonance of inhibitory neurons would fail to become entrained.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Correlated physiological and perceptual effects of noise in a tactile stimulus

Lak

Arabzadeh²,

Harris³

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

We investigated connections between the physiology of rat barrel cortex neurons and the sensation of vibration in humans. One set of experiments measured neuronal responses in anesthetized rats to trains of whisker deflections, each train characterized either by constant amplitude across all deflections or by variable amplitude ("amplitude noise"). Firing rate and firing synchrony were, on average, boosted by the presence of noise. However, neurons were not uniform in their responses to noise. Barrel cortex neurons have been categorized as regular-spiking units (putative excitatory neurons) and fast-spiking units (putative inhibitory neurons). Among regular-spiking units, amplitude noise caused a higher firing rate and increased cross-neuron synchrony. Among fast-spiking units, noise had the opposite effect: It led to a lower firing rate and decreased cross-neuron synchrony. This finding suggests that amplitude noise affects the interaction between inhibitory and excitatory neurons. From these physiological effects, we expected that noise would lead to an increase in the perceived intensity of a vibration. We tested this notion using psychophysical measurements in humans. As predicted, subjects overestimated the intensity of noisy vibrations. Thus the physiological mechanisms present in barrel cortex also appear to be at work in the human tactile system, where they affect vibration perception.psychophysics | somatosensory cortex | vibration | whisker | finger A n effective approach to uncover how neuronal activity leads to sensation is to vary stimulation parameters while correlating changes in firing with changes in the percept (1-5). In the present work, we measured changes in neuronal activity in rat somatosensory ("barrel") cortex induced by variation in vibration parameters and correlated these changes with perceptual reports from human subjects. The stimuli in the two cases were trains of whisker and skin vibration, respectively.Isolated neurons respond more robustly to unpredictable (noisy) patterns of electrical stimulation than to repeating, periodic patterns (6) or constant inputs (7). Synaptic transmission also can be enhanced by noise (8). In a recent study of the effects of stimulus noise in rat barrel cortex, we found that whisker vibration trains containing temporal noise (irregularity in the sequence of interdeflection intervals) evoked a larger and more synchronous cortical response than did periodic vibration trains (9). In the present work, to verify that response amplification by noise is a general property of the sensory system, we explored another stimulus feature: We compared cortical responses to trains that had constant amplitude vs. trains that had varying amplitude. We then investigated the perceptual impact of noise using psychophysical experiments in humans. We predicted that noise, by enhancing neuronal firing rates and/or firing synchrony in somatosensory cortex, would produce a systematic bias in the perceived intensity of noisy vibrations compared with noise-free vibrations. Resu...

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Correlated physiological and perceptual effects of noise in a tactile stimulus

Lak

Arabzadeh²,

Harris³

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…The first pair of features is inspired by inspection of sampled whisker signals. The other two pairs are inspired by previous neurophysiological [2] and modeling [17], [23] investigations of the rat vibrissal system. In each case we present raw scatter plots of the data classes under the features, and confusion matrices obtained using a standard Gaussian classifier [7].…”

Section: Data Collectionmentioning

confidence: 99%

“…In vivo animal experiments [2] played pure sinusoidal vibration stimulations into whiskers and found cortical cells responded to the product Xω of the amplitude and frequency of these vibrations. Texture experiments [3] generalized this, playing back pre-recorded texture vibrations, and the best found feature responded to by cortical neurons was…”

Section: Biologically Inspired Frequency Features From Cortical Respomentioning

confidence: 99%

Contact type dependency of texture classification in a whiskered mobile robot

et al. 2009

View full text Add to dashboard Cite

Actuated artificial whiskers modeled on rat macrovibrissae can provide effective tactile sensor systems for autonomous robots. This article focuses on texture classification using artificial whiskers and addresses a limitation of previous studies, namely, their use of whisker deflection signals obtained under relatively constrained experimental conditions. Here we consider the classification of signals obtained from a whiskered robot required to explore different surface textures from a range of orientations and distances. This procedure resulted in a variety of deflection signals for any given texture. Using a standard Gaussian classifier we show, using both hand-picked features and ones derived from studies of rat vibrissal processing, that a robust rough-smooth discrimination is achievable without any knowledge of how the whisker interacts with the investigated object. On the other hand, finer discriminations appear to require knowledge of the target's relative position and/or of the manner in which the whisker contact its surface. (146 words)

show abstract

“…To date, the electrophysiological properties and underlying synaptic inputs responsible for creating the temporally selective responses of DTNs have been a major research focus, but a quantitative analysis of the information content and encoding efficiency of any neural system is important for linking neurophysiology to behavior and perception because it can suggest limits on the efficacy of information representation. Information theoretic measurements have previously been used to characterize the spiking responses of visual (Strong et al 1998;Tolhurst et al 2009), auditory (Hsu et al 2004;Montgomery and Wehr 2010;Kayser et al 2010), somatosensory (Arabzadeh 2004;Saal et al 2009;Panzeri and Diamond 2010), olfactory (Rolls et al 1996(Rolls et al , 2009, and electrosensory neurons (Carlson and Kawasaki 2008;Maler 2009;Vonderschen and Chacron 2014). In this study, we used an information theory-based approach to analyze the information available in the responses of auditory DTNs from the mammalian IC.…”

mentioning

confidence: 99%

Decoding stimulus duration from neural responses in the auditory midbrain

Aubie

Sayegh

Fremouw

et al. 2014

Journal of Neurophysiology

View full text Add to dashboard Cite

(DTNs). Temporal specificity in their spiking suggests that one function of DTNs is to encode stimulus duration; however, the efficacy of duration encoding by DTNs has yet to be investigated. Herein, we characterize the information content of individual cells and a population of DTNs from the mammalian inferior colliculus (IC) by measuring the stimulus-specific information (SSI) and estimated Fisher information (FI) of spike count responses. We found that SSI was typically greatest for those stimulus durations that evoked maximum spike counts, defined as best duration (BD) stimuli, and that FI was maximal for stimulus durations off BD where sensitivity to a change in duration was greatest. Using population data, we demonstrate that a maximum likelihood estimator (MLE) can accurately decode stimulus duration from evoked spike counts. We also simulated a two-alternative forced choice task by having MLE models decide whether two durations were the same or different. With this task we measured the just-noticeable difference threshold for stimulus duration and calculated the corresponding Weber fractions across the stimulus domain. Altogether, these results demonstrate that the spiking responses of DTNs from the mammalian IC contain sufficient information for the CNS to encode, decode, and discriminate behaviorally relevant auditory signal durations. big brown bat; Eptesicus fuscus; Fisher information, inferior colliculus; just-noticeable difference; stimulus-specific information, temporal processing; Weber fraction DURATION-TUNED NEURONS (DTNs) are ideal candidates for encoding spectral, intensity, and temporal information about an auditory stimulus because they respond selectively to the frequency, amplitude, and duration of acoustic signals. First reported in the torus semicircularis of frogs and subsequently the inferior colliculus (IC) of bats, DTNs have now been recorded from the auditory midbrain, thalamus, and cortex in a variety of vertebrates, and from the mammalian visual cortex (see Sayegh et al. 2011, for review). To date, the electrophysiological properties and underlying synaptic inputs responsible for creating the temporally selective responses of DTNs have been a major research focus, but a quantitative analysis of the information content and encoding efficiency of any neural system is important for linking neurophysiology to behavior and perception because it can suggest limits on the efficacy of information representation. Information theoretic measurements have previously been used to characterize the spiking responses of visual (Strong et al. 1998;Tolhurst et al. 2009 Sensory neurons in general, and auditory neurons in particular, are often viewed as feature detectors that have a preferred value in stimulus domains such as frequency or amplitude, and they encode the domain with spike counts (or rates) and latencies that vary as a function of the stimulus. We measured spike counts and latencies from auditory DTNs in the mammalian IC to characterize the information content of duration-selective ne...

show abstract

Whisker Vibration Information Carried by Rat Barrel Cortex Neurons

Cited by 137 publications

References 46 publications

Correlated physiological and perceptual effects of noise in a tactile stimulus

Correlated physiological and perceptual effects of noise in a tactile stimulus

Contact type dependency of texture classification in a whiskered mobile robot

Decoding stimulus duration from neural responses in the auditory midbrain

Contact Info

Product

Resources

About