Natural scenes in tactile texture

2014 ◽  
Vol 111 (9) ◽  
pp. 1792-1802 ◽  
Author(s):  
Louise R. Manfredi ◽  
Hannes P. Saal ◽  
Kyler J. Brown ◽  
Mark C. Zielinski ◽  
John F. Dammann ◽  
...  
Keyword(s):  
Sensory System ◽  
Laser Doppler Vibrometer ◽  
Relevant Information ◽  
Biomechanical Properties ◽  
Natural Scenes ◽  
Textured Surfaces ◽  
Neural Responses ◽  
Texture Perception ◽  
Neural Basis ◽  
Surface Microgeometry

Sensory systems are designed to extract behaviorally relevant information from the environment. In seeking to understand a sensory system, it is important to understand the environment within which it operates. In the present study, we seek to characterize the natural scenes of tactile texture perception. During tactile exploration complex high-frequency vibrations are elicited in the fingertip skin, and these vibrations are thought to carry information about the surface texture of manipulated objects. How these texture-elicited vibrations depend on surface microgeometry and on the biomechanical properties of the fingertip skin itself remains to be elucidated. Here we record skin vibrations, using a laser-Doppler vibrometer, as various textured surfaces are scanned across the finger. We find that the frequency composition of elicited vibrations is texture specific and highly repeatable. In fact, textures can be classified with high accuracy on the basis of the vibrations they elicit in the skin. As might be expected, some aspects of surface microgeometry are directly reflected in the skin vibrations. However, texture vibrations are also determined in part by fingerprint geometry. This mechanism enhances textural features that are too small to be resolved spatially, given the limited spatial resolution of the neural signal. We conclude that it is impossible to understand the neural basis of texture perception without first characterizing the skin vibrations that drive neural responses, given the complex dependence of skin vibrations on both surface microgeometry and fingertip biomechanics.

scholarly journals Frequency-Dependent Processing in the Vibrissa Sensory System

2004 ◽  
Vol 91 (6) ◽  
pp. 2390-2399 ◽  
Author(s):  
Christopher I. Moore
Keyword(s):  
High Frequency ◽  
Sensory System ◽  
Low Frequency ◽  
Biomechanical Properties ◽  
Textured Surfaces ◽  
Neural Responses ◽  
Processing Modes ◽  
Stimulus Features ◽  
Active Exploration ◽  
40 Hz

The vibrissa sensory system is a key model for investigating principles of sensory processing. Specific frequency ranges of vibrissa motion, generated by rodent sensory behaviors (e.g., active exploration or resting) and by stimulus features, characterize perception by this system. During active exploration, rats typically sweep their vibrissae at ∼4–12 Hz against and over tactual surfaces, and during rest or quiescence, their vibrissae are typically still (<1 Hz). When a vibrissa is swept over an object, microgeometric surface features (e.g., grains on sandpaper) likely create higher frequency vibrissa vibrations that are greater than or equal to several hundred Hertz. In this article, I first review thalamic and cortical neural responses to vibrissa stimulation at 1–40 Hz. I then propose that neural dynamics optimize the detection of stimuli in low-frequency contexts (e.g., 1 Hz) and the discrimination of stimuli in the whisking frequency range. In the third section, I describe how the intrinsic biomechanical properties of vibrissae, their ability to resonate when stimulated at specific frequencies, may promote detection and discrimination of high-frequency inputs, including textured surfaces. In the final section, I hypothesize that distinct low- and high-frequency processing modes may exist in the somatosensory cortex (SI), such that neural responses to stimuli at 1–40 Hz do not necessarily predict responses to higher frequency inputs. In total, these studies show that several frequency-specific mechanisms impact information transmission in the vibrissa sensory system and suggest that these properties play a crucial role in perception.

scholarly journals Postural Representations of the Hand in Primate Sensorimotor Cortex

2019 ◽  
Author(s):  
James M. Goodman ◽  
Gregg A. Tabot ◽  
Alex S. Lee ◽  
Aneesha K. Suresh ◽  
Alexander T. Rajan ◽  
...  
Keyword(s):  
Motor System ◽  
Sensory System ◽  
Reaching Movements ◽  
Hand Movements ◽  
Time Varying ◽  
Neural Responses ◽  
Neural Basis ◽  
Functional Roles ◽  
Hand Control ◽  
Dexterous Hand

SummaryDexterous hand control requires not only a sophisticated motor system but also a sensory system to provide tactile and proprioceptive feedback. To date, the study of the neural basis of proprioception in cortex has focused primarily on reaching movements, at the expense of hand-specific behaviors such as grasp. To fill this gap, we record both the time-varying hand kinematics and the neural activity evoked in somatosensory and motor cortices as monkeys grasp a variety of different objects. We find that neurons in somatosensory cortex, as well as in motor cortex, preferentially track postures of multi-joint combinations spanning the entire hand. This contrasts with neural responses during reaching movements, which preferentially track movement kinematics of the arm rather than its postural configuration. These results suggest different representations of arm and hand movements likely adapted to suit the different functional roles of these two effectors.

scholarly journals Evidence accumulation relates to perceptual consciousness and monitoring

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Michael Pereira ◽  
Pierre Megevand ◽  
Mi Xue Tan ◽  
Wenwen Chang ◽  
Shuo Wang ◽  
...  
Keyword(s):  
Posterior Parietal Cortex ◽  
Detection Threshold ◽  
Task Demands ◽  
Neuron Activity ◽  
Neural Responses ◽  
Neuronal Responses ◽  
Neural Basis ◽  
Perceptual Consciousness ◽  
Evidence Accumulation ◽  
Posterior Parietal

AbstractA fundamental scientific question concerns the neural basis of perceptual consciousness and perceptual monitoring resulting from the processing of sensory events. Although recent studies identified neurons reflecting stimulus visibility, their functional role remains unknown. Here, we show that perceptual consciousness and monitoring involve evidence accumulation. We recorded single-neuron activity in a participant with a microelectrode in the posterior parietal cortex, while they detected vibrotactile stimuli around detection threshold and provided confidence estimates. We find that detected stimuli elicited neuronal responses resembling evidence accumulation during decision-making, irrespective of motor confounds or task demands. We generalize these findings in healthy volunteers using electroencephalography. Behavioral and neural responses are reproduced with a computational model considering a stimulus as detected if accumulated evidence reaches a bound, and confidence as the distance between maximal evidence and that bound. We conclude that gradual changes in neuronal dynamics during evidence accumulation relates to perceptual consciousness and perceptual monitoring in humans.

scholarly journals Rapid neural representations of personally relevant faces

2019 ◽  
Author(s):  
Mareike Bayer ◽  
Oksana Berhe ◽  
Isabel Dziobek ◽  
Tom Johnstone
Keyword(s):  
Time Course ◽  
Primary Source ◽  
Relevant Information ◽  
Neural Circuitry ◽  
Romantic Partners ◽  
Personal Relevance ◽  
Neural Responses ◽  
Emotional Faces ◽  
Neural Representations ◽  
Processing Network

AbstractThe faces of those most personally relevant to us are our primary source of social information, making their timely perception a priority. Recent research indicates that gender, age and identity of faces can be decoded from EEG/MEG data within 100ms. Yet the time course and neural circuitry involved in representing the personal relevance of faces remain unknown. We applied simultaneous EEG-fMRI to examine neural responses to emotional faces of female participants’ romantic partners, friends, and a stranger. Combining EEG and fMRI in cross-modal representational similarity analyses, we provide evidence that representations of personal relevance start prior to structural encoding at 100ms in visual cortex, but also in prefrontal and midline regions involved in value representation, and monitoring and recall of self-relevant information. Representations related to romantic love emerged after 300ms. Our results add to an emerging body of research that suggests that models of face perception need to be updated to account for rapid detection of personal relevance in cortical circuitry beyond the core face processing network.

scholarly journals Perceptual Content, Not Physiological Signals, Determines Perceived Duration When Viewing Dynamic, Natural Scenes

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Marta Suárez-Pinilla ◽  
Kyriacos Nikiforou ◽  
Zafeirios Fountas ◽  
Anil K. Seth ◽  
Warrick Roseboom
Keyword(s):  
Time Perception ◽  
Physiological Signals ◽  
Perceptual Content ◽  
Natural Scenes ◽  
Neural Basis ◽  
Recent Proposal ◽  
Physiological Factors ◽  
Physiological Processes ◽  
Scene Content ◽  
Perceived Duration

The neural basis of time perception remains unknown. A prominent account is the pacemaker-accumulator model, wherein regular ticks of some physiological or neural pacemaker are read out as time. Putative candidates for the pacemaker have been suggested in physiological processes (heartbeat), or dopaminergic mid-brain neurons, whose activity has been associated with spontaneous blinking. However, such proposals have difficulty accounting for observations that time perception varies systematically with perceptual content. We examined physiological influences on human duration estimates for naturalistic videos between 1–64 seconds using cardiac and eye recordings. Duration estimates were biased by the amount of change in scene content. Contrary to previous claims, heart rate, and blinking were not related to duration estimates. Our results support a recent proposal that tracking change in perceptual classification networks provides a basis for human time perception, and suggest that previous assertions of the importance of physiological factors should be tempered.

scholarly journals Model Constrained by Visual Hierarchy Improves Prediction of Neural Responses to Natural Scenes

2016 ◽  
Vol 12 (6) ◽  
pp. e1004927 ◽  
Author(s):  
Ján Antolík ◽  
Sonja B. Hofer ◽  
James A. Bednar ◽  
Thomas D. Mrsic-Flogel
Keyword(s):  
Natural Scenes ◽  
Neural Responses ◽  
Visual Hierarchy

scholarly journals A reduced somatosensory gating response in individuals with multiple sclerosis is related to walking impairment

2017 ◽  
Vol 118 (4) ◽  
pp. 2052-2058 ◽  
Author(s):  
David J. Arpin ◽  
James E. Gehringer ◽  
Tony W. Wilson ◽  
Max J. Kurz
Keyword(s):  
Multiple Sclerosis ◽  
Sensory Gating ◽  
Healthy Controls ◽  
Neural Responses ◽  
Neural Basis ◽  
Tactile Discrimination ◽  
Mobility Impairments ◽  
Gait Kinematics ◽  
Walking Performance ◽  
Somatosensory Gating

When identical stimuli are presented in rapid temporal succession, neural responses to the second stimulation are often weaker than those observed for the first. This phenomenon is termed sensory gating and is believed to be an adaptive feature that helps prevent higher-order cortical centers from being flooded with unnecessary information. Recently, sensory gating in the somatosensory system has been linked to deficits in tactile discrimination. Additionally, studies have linked poor tactile discrimination with impaired walking and balance in individuals with multiple sclerosis (MS). In this study, we examine the neural basis of somatosensory gating in patients with MS and healthy controls and assess the relationship between somatosensory gating and walking performance. We used magnetoencephalography to record neural responses to paired-pulse electrical stimulation applied to the right posterior tibial nerve. All participants also walked across a digital mat, which recorded their spatiotemporal gait kinematics. Our results showed the amplitude of the response to the second stimulation was sharply reduced only in controls, resulting in a significantly reduced somatosensory gating in the patients with MS. No group differences were observed in the amplitude of the response to the first stimulation nor the latency of the neural response to either the first or second stimulation. Interestingly, the altered somatosensory gating responses were correlated with aberrant spatiotemporal gait kinematics in the patients with MS. These results suggest that inhibitory GABA circuits may be altered in patients with MS, which impacts somatosensory gating and contributes to the motor performance deficits seen in these patients. NEW & NOTEWORTHY We aimed to determine whether somatosensory gating in patients with multiple sclerosis (MS) differed compared with healthy controls and whether a relationship exists between somatosensory gating and walking performance. We found reduced somatosensory gating responses in patients with MS, and these altered somatosensory gating responses were correlated with the mobility impairments. These novel findings show that somatosensory gating is impaired in patients with MS and is related to the mobility impairments seen in these patients.

scholarly journals Intelligence moderates reinforcement learning: a mini-review of the neural evidence

2015 ◽  
Vol 113 (10) ◽  
pp. 3459-3461 ◽  
Author(s):  
Chong Chen
Keyword(s):  
Reinforcement Learning ◽  
Prediction Error ◽  
Dorsolateral Prefrontal Cortex ◽  
Anterior Cingulate ◽  
Neural Responses ◽  
Key Factors ◽  
Neural Basis ◽  
Dorsal Anterior Cingulate Cortex ◽  
Neural Signal ◽  
Dorsolateral Prefrontal

Our understanding of the neural basis of reinforcement learning and intelligence, two key factors contributing to human strivings, has progressed significantly recently. However, the overlap of these two lines of research, namely, how intelligence affects neural responses during reinforcement learning, remains uninvestigated. A mini-review of three existing studies suggests that higher IQ (especially fluid IQ) may enhance the neural signal of positive prediction error in dorsolateral prefrontal cortex, dorsal anterior cingulate cortex, and striatum, several brain substrates of reinforcement learning or intelligence.

scholarly journals Cortical Mechanisms of Cognitive Control for Shifting Attention in Vision and Working Memory

2011 ◽  
Vol 23 (10) ◽  
pp. 2905-2919 ◽  
Author(s):  
Benjamin J. Tamber-Rosenau ◽  
Michael Esterman ◽  
Yu-Chin Chiu ◽  
Steven Yantis
Keyword(s):  
Working Memory ◽  
Cognitive Control ◽  
Relevant Information ◽  
Neural Basis ◽  
Cognitive Domains ◽  
Future Goals ◽  
Spatio Temporal ◽  
Past Experiences ◽  
Selection Of ◽  
Superior Frontal Sulcus

Organisms operate within both a perceptual domain of objects and events, and a mnemonic domain of past experiences and future goals. Each domain requires a deliberate selection of task-relevant information, through deployments of external (perceptual) and internal (mnemonic) attention, respectively. Little is known about the control of attention shifts in working memory, or whether voluntary control of attention in these two domains is subserved by a common or by distinct functional networks. We used human fMRI to examine the neural basis of cognitive control while participants shifted attention in vision and in working memory. We found that these acts of control recruit in common a subset of the dorsal fronto-parietal attentional control network, including the medial superior parietal lobule, intraparietal sulcus, and superior frontal sulcus/gyrus. Event-related multivoxel pattern classification reveals, however, that these regions exhibit distinct spatio-temporal patterns of neural activity during internal and external shifts of attention, respectively. These findings constrain theoretical accounts of selection in working memory and perception by showing that populations of neurons in dorsal fronto-parietal network regions exhibit selective tuning for acts of cognitive control in different cognitive domains.

Sign in / Sign up

Export Citation Format

Share Document