Tactile representation of the head and shoulders assessed by fMRI in the nonhuman primate

In nonhuman primates, tactile representation at the cortical level has mostly been studied using single-cell recordings targeted to specific cortical areas. In this study, we explored the representation of tactile information delivered to the face or the shoulders at the whole brain level, using functional magnetic resonance imaging (fMRI) in the nonhuman primate. We used air puffs delivered to the center of the face, the periphery of the face, or the shoulders. These stimulations elicited activations in numerous cortical areas, encompassing the primary and secondary somatosensory areas, prefrontal and premotor areas, and parietal, temporal, and cingulate areas as well as low-level visual cortex. Importantly, a specific parieto-temporo-prefrontal network responded to the three stimulations but presented a marked preference for air puffs directed to the center of the face. This network corresponds to areas that are also involved in near-space representation, as well as in the multisensory integration of information at the interface between this near space and the skin of the face, and is probably involved in the construction of a peripersonal space representation around the head.

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Cortical networks for encoding near and far space in the non-human primate

10.1101/261677 ◽

2018 ◽

Author(s):

Justine Cléry ◽

Olivier Guipponi ◽

Soline Odouard ◽

Claire Wardak ◽

Suliann Ben Hamed

Keyword(s):

Personal Space ◽

Peripersonal Space ◽

The Body ◽

The Other ◽

Space Representation ◽

List Type ◽

Cortical Networks ◽

Near Space ◽

Space Processing ◽

Human Primate

AbstractWhile extra-personal space is often erroneously considered as a unique entity, early neuropsychological studies report a dissociation between near and far space processing both in humans and in monkeys. Here, we use functional MRI in a naturalistic 3D environment to describe the non-human primate near and far space cortical networks. We describe the co-occurrence of two extended functional networks respectively dedicated to near and far space processing. Specifically, far space processing involves occipital, temporal, parietal, posterior cingulate as well as orbitofrontal regions not activated by near space, possibly subserving the processing of the shape and identity of objects. In contrast, near space processing involves temporal, parietal and prefrontal regions not activated by far space, possibly subserving the preparation of an arm/hand mediated action in this proximal space. Interestingly, this network also involves somatosensory regions, suggesting a cross-modal anticipation of touch by a nearby object. Last, we also describe cortical regions that process both far and near space with a preference for one or the other. This suggests a continuous encoding of relative distance to the body, in the form of a far-to-near gradient. We propose that these cortical gradients in space representation subserve the physically delineable peripersonal spaces described in numerous psychology and psychophysics studies.HighlightsNear space processing involves temporal, parietal and prefrontal regions.Far space activates occipital, temporal, parietal, cingulate & orbitofrontal areas.Most regions process both far & near space, with a preference for one or the other.Far-to-near gradient may subserve behavioral changes in peripersonal space size.

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Parallel processing in rabbit first (SI) and second (SII) somatosensory cortical areas: effects of reversible inactivation by cooling of SI on responses in SII

Journal of Neurophysiology ◽

10.1152/jn.1992.68.3.703 ◽

1992 ◽

Vol 68 (3) ◽

pp. 703-710 ◽

Cited By ~ 26

Author(s):

G. M. Murray ◽

H. Q. Zhang ◽

A. N. Kaye ◽

T. Sinnadurai ◽

D. H. Campbell ◽

...

Keyword(s):

Mammalian Species ◽

Receptive Fields ◽

Activity Levels ◽

Tactile Information ◽

Reversible Inactivation ◽

Cortical Areas ◽

Tactile Stimuli ◽

The Face ◽

Somatosensory Cortical Areas ◽

Hierarchical Scheme

1. Previous observations on the effect of ablation or inactivation of the primary somatosensory cortex (SI) on the responses of neurons within the second somatosensory area (SII) to tactile stimuli point to profound differences between monkeys and certain other mammals in the organization of thalamocortical systems. In the cat, for example, tactile information appears to be conveyed in parallel from the thalamus to both SI and SII, whereas, in macaque and marmoset monkeys, it is conveyed in a serial (or hierarchical) scheme from the thalamus to SI and thence to SII. The present study examined the responses of individual SII neurons during reversible, cooling-induced inactivation of SI in another nonprimate placental mammal, the rabbit, to obtain further evidence on whether the above differences might reflect a fundamental distinction between simian primates and other mammalian species. 2. When the temperature at the face of a silver cooling block over the forepaw and hindpaw regions of SI was lowered to 5–13 degrees C, the SI surface potentials evoked by brief tactile stimuli were abolished (indicative of SI inactivation), whereas SII potentials remained intact. 3. The responses of 25 SII neurons to controlled tactile stimuli (consisting of 1- to 1.5-s trains of vibration or rectangular mechanical pulses) were studied before, during, and after inactivation of SI. The effects on the spontaneous activity of a further three SII neurons that lacked identified receptive fields were also studied. 4. The response or activity levels of 26 of the 28 SII neurons examined (93%) were unaffected by SI inactivation.(ABSTRACT TRUNCATED AT 250 WORDS)

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Density, Experience, and the Other-race Effect: Implications for the Face Space Representation

PsycEXTRA Dataset ◽

10.1037/e413812005-500 ◽

2002 ◽

Author(s):

Heather A. Wild ◽

Thomas A. Busey

Keyword(s):

The Other ◽

Space Representation ◽

Face Space ◽

Race Effect ◽

The Face

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Serial and parallel processing of tactual information in somatosensory cortex of rhesus monkeys

Journal of Neurophysiology ◽

10.1152/jn.1992.68.2.518 ◽

1992 ◽

Vol 68 (2) ◽

pp. 518-527 ◽

Cited By ~ 124

Author(s):

T. P. Pons ◽

P. E. Garraghty ◽

M. Mishkin

Keyword(s):

Substantial Reduction ◽

Receptive Fields ◽

Somatosensory System ◽

Encounter Rate ◽

Specific Information ◽

Tactile Information ◽

Cortical Areas ◽

Area 3A ◽

Area 3B ◽

Made In

1. Selective ablations of the hand representations in postcentral cortical areas 3a, 3b, 1, and 2 were made in different combinations to determine each area's contribution to the responsivity and modality properties of neurons in the hand representation in SII. 2. Ablations that left intact only the postcentral areas that process predominantly cutaneous inputs (i.e., areas 3b and 1) yielded SII recording sites responsive to cutaneous stimulation and none driven exclusively by high-intensity or "deep" stimulation. Conversely, ablations that left intact only the postcentral areas that process predominantly deep receptor inputs (i.e., areas 3a and 2) yielded mostly SII recording sites that responded exclusively to deep stimulation. 3. Ablations that left intact only area 3a or only area 2 yielded substantial and roughly equal reductions in the number of deep receptive fields in SII. By contrast, ablations that left intact only area 3b or only area 1 yielded unequal reductions in the number of cutaneous receptive fields in SII: a small reduction when area 3b alone was intact but a somewhat larger one when only area 1 was intact. 4. Finally, when the hand representation in area 3b was ablated, leaving areas 3a, 1, and 2 fully intact, there was again a substantial reduction in the encounter rate of cutaneous receptive fields. 5. The partial ablations often led to unresponsive sites in the SII hand representation. In SII representations other than of the hand no such unresponsive sites were found and there were no substantial changes in the ratio of cutaneous to deep receptive fields, indicating that the foregoing results were not due to long-lasting postsurgical depression or effects of anesthesia. 6. The findings indicate that modality-specific information is relayed from postcentral cortical areas to SII along parallel channels, with cutaneous inputs transmitted via areas 3b and 1, and deep inputs via areas 3a and 2. Further, area 3b provides the major source of cutaneous input to SII, directly and perhaps also via area 1. 7. The results are in line with accumulating anatomic and electrophysiologic evidence pointing to an evolutionary shift in the organization of the somatosensory system from the general mammalian plan, in which tactile information is processed in parallel in SI and SII, to a new organization in higher primates in which the processing of tactile information proceeds serially from SI to SII. The presumed functional advantages of this evolutionary shift are unknown.

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Representational drift in the mouse visual cortex

10.1101/2020.10.05.327049 ◽

2020 ◽

Cited By ~ 1

Author(s):

Daniel Deitch ◽

Alon Rubin ◽

Yaniv Ziv

Keyword(s):

Large Scale ◽

Activity Patterns ◽

Population Level ◽

Population Activity ◽

Cortical Areas ◽

Electrophysiological Recordings ◽

The Face ◽

Visual Cortical ◽

Mouse Visual Cortex ◽

Over Time

AbstractNeuronal representations in the hippocampus and related structures gradually change over time despite no changes in the environment or behavior. The extent to which such ‘representational drift’ occurs in sensory cortical areas and whether the hierarchy of information flow across areas affects neural-code stability have remained elusive. Here, we address these questions by analyzing large-scale optical and electrophysiological recordings from six visual cortical areas in behaving mice that were repeatedly presented with the same natural movies. We found representational drift over timescales spanning minutes to days across multiple visual areas. The drift was driven mostly by changes in individual cells’ activity rates, while their tuning changed to a lesser extent. Despite these changes, the structure of relationships between the population activity patterns remained stable and stereotypic, allowing robust maintenance of information over time. Such population-level organization may underlie stable visual perception in the face of continuous changes in neuronal responses.

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Capturing the dynamics of peripersonal space by integrating sound propagation properties and expectancy effects

10.1101/756783 ◽

2019 ◽

Author(s):

Lise Hobeika ◽

Marine Taffou ◽

Thibaut Carpentier ◽

Olivier Warusfel ◽

Isabelle Viaud-Delmon

Keyword(s):

Sound Propagation ◽

Current Method ◽

Peripersonal Space ◽

The Body ◽

Logarithmic Scale ◽

List Type ◽

Expectancy Effects ◽

Near Space ◽

Propagation Properties ◽

Tactile Integration

AbstractHighlightsLogarithmically distributed auditory distances provides an apt granularity of PPSMeasuring expectation helps to interpret behavioral impact of audiotactile integrationTactile RTs follows a logarithmic decrease due to audiotactile integrationPeripersonal space is better characterized and quantified with this refinementBackgroundHumans perceive near space and far space differently. Peripersonal space, i.e. the space directly surrounding the body, is often studied using paradigms based on auditory-tactile integration. In these paradigms, reaction time to a tactile stimulus is measured in the presence of a concurrent auditory looming stimulus.New MethodWe propose here to refine the experimental procedure considering sound propagation properties in order to improve granularity and relevance of auditory-tactile integration measures. We used a logarithmic distribution of distances for this purpose. We also want to disentangle behavioral contributions of the targeted audiotactile integration mechanisms from expectancy effects. To this aim, we added to the protocol a baseline with a fixed sound distance.ResultsExpectation contributed significantly to overall behavioral responses. Subtracting it isolated the audiotactile effect due to the stimulus proximity. This revealed that audiotactile integration effects have to be tested on a logarithmic scale of distances, and that they follow a linear variation on this scale.Comparison with Existing Method(s)The granularity of the current method is more relevant, providing higher spatial resolution in the vicinity of the body. Furthermore, most of the existing methods propose a sigmoid fitting, which rests on the intuitive framework that PPS is an in-or-out zone. Our results suggest that behavioral effects follow a logarithmic decrease, thus a response graduated in space.ConclusionsThe proposed protocol design and method of analysis contribute to refine the experimental investigation of the factors influencing and modifying multisensory integration phenomena in the space surrounding the body.

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Visuotactile Representation of Peripersonal Space: A Neural Network Study

Neural Computation ◽

10.1162/neco.2009.01-08-694 ◽

2010 ◽

Vol 22 (1) ◽

pp. 190-243 ◽

Cited By ~ 26

Author(s):

Elisa Magosso ◽

Melissa Zavaglia ◽

Andrea Serino ◽

Giuseppe di Pellegrino ◽

Mauro Ursino

Keyword(s):

Neural Network ◽

Peripersonal Space ◽

Sensitivity Analyses ◽

Neurological Deficits ◽

Inhibitory Synapses ◽

Space Representation ◽

Emergent Properties ◽

Bilateral Stimulation ◽

The Right ◽

Parameter Values

Neurophysiological and behavioral studies suggest that the peripersonal space is represented in a multisensory fashion by integrating stimuli of different modalities. We developed a neural network to simulate the visual-tactile representation of the peripersonal space around the right and left hands. The model is composed of two networks (one per hemisphere), each with three areas of neurons: two are unimodal (visual and tactile) and communicate by synaptic connections with a third downstream multimodal (visual-tactile) area. The hemispheres are interconnected by inhibitory synapses. We applied a combination of analytic and computer simulation techniques. The analytic approach requires some simplifying assumptions and approximations (linearization and a reduced number of neurons) and is used to investigate network stability as a function of parameter values, providing some emergent properties. These are then tested and extended by computer simulations of a more complex nonlinear network that does not rely on the previous simplifications. With basal parameter values, the extended network reproduces several in vivo phenomena: multisensory coding of peripersonal space, reinforcement of unisensory perception by multimodal stimulation, and coexistence of simultaneous right- and left-hand representations in bilateral stimulation. By reducing the strength of the synapses from the right tactile neurons, the network is able to mimic the responses characteristic of right-brain-damaged patients with left tactile extinction: perception of unilateral left tactile stimulation, cross-modal extinction and cross-modal facilitation in bilateral stimulation. Finally, a variety of sensitivity analyses on some key parameters was performed to shed light on the contribution of single-model components in network behaviour. The model may help us understand the neural circuitry underlying peripersonal space representation and identify its alterations explaining neurological deficits. In perspective, it could help in interpreting results of psychophysical and behavioral trials and clarifying the neural correlates of multisensory-based rehabilitation procedures.

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