scholarly journals Tickle contagion in the somatosensory cortex

2021 ◽  
Author(s):  
Lena V Kaufmann ◽  
Michael Brecht ◽  
Shimpei Ishiyama
Keyword(s):  
Somatosensory Cortex ◽  
Mirror Neurons ◽  
Behavioral Responses ◽  
Emotional Contagion ◽  
Cortical Layers ◽  
Cellular Mechanisms ◽  
Specific Manner ◽  
Somatosensory Neurons

The cellular mechanisms of emotional contagion are unknown. We investigated tickle contagion and the underlying neuronal representations in rats. We recorded trunk somatosensory cortex activity of observer rats while they received tickling, audio-visual playback of tickling footage, and while they witnessed tickling of demonstrator rats. Observers vocalized, and showed "Freudenspruenge" ("joy jumps") during witnessing live tickling, while they showed little behavioral responses to playbacks. A fraction of trunk somatosensory neurons responded to both direct and witnessed tickling in action-specific manner. The correlation between direct and witnessed tickling responses increased towards deeper cortical layers. Tickle-mirror neurons but not non-mirror neurons discharged prior to and during vocalizations and hence might drive contagious 'laughter'. We conclude that trunk somatosensory cortex represents mirrored ticklishness.

Transient and prolonged effects of acetylcholine on responsiveness of cat somatosensory cortical neurons

1988 ◽  
Vol 59 (4) ◽  
pp. 1253-1276 ◽  
Author(s):  
R. Metherate ◽  
N. Tremblay ◽  
R. W. Dykes
Keyword(s):  
Receptive Field ◽  
Somatosensory Cortex ◽  
Cortical Neurons ◽  
Receptive Fields ◽  
Fixed Dose ◽  
Cortical Layers ◽  
Afferent Inputs ◽  
Time Periods ◽  
Layer I ◽  
Layer Vi

1. Two-hundred and seven neurons were examined for changes in their responsiveness during the iontophoretic administration of acetylcholine (ACh) in barbiturate-anesthetized cats. 2. The laminar locations of 78 cells were determined. Cholinoceptive neurons were found in all cortical layers and ranged from 50% of the cells tested in layer I to 78% in layer VI. 3. When the responsiveness of a neuron was measured by the magnitude of the discharge generated by a fixed dose of glutamate, 30 of 47 cases (64%) were potentiated, and 4 (8%) were depressed when ACh was administered during glutamate-induced excitation. 4. ACh administered during glutamate excitation was significantly more effective in altering neuronal responsiveness than was ACh administered alone (P less than 0.001). 5. When the responsiveness of a neuron was measured by the magnitude of the discharge generated by a standard somatic stimulus applied to the receptive field, 42 of 52 cases (81%) were potentiated during ACh application. This was again different from ACh treatment alone where only 4 of 27 tests (15%) resulted in subsequent enhancement of the response to somatic stimuli. 6. ACh generally increased the responsiveness of neurons with peripheral receptive fields and caused the appearance of a receptive field in some cells lacking one. 7. In many cases the changes in excitability, as measured by responses either to glutamate or to somatic stimulation, remained for prolonged time periods. When glutamate was used to test excitability, 34% (16 of 47) of the enhancements lasted more than 5 min. When somatic stimuli were used 29% (15 of 52) lasted more than 5 min. With both measures some neurons still displayed enhanced responses more than 1 h after the treatment with ACh. 8. ACh appears to act as a permissive agent that allows modification of the effectiveness with which previously existing afferent inputs drive somatosensory cortical neurons. 9. This mechanism to alter neuronal responsiveness has many of the characteristics necessary to account for the reorganization observed in somatosensory cortex following alterations in its afferent drive and may be related to some forms of learning and memory.

scholarly journals Histochemical localization of potassium-stimulated P-nitrophenylphosphatase activity in the somatosensory cortex of the rat.

1976 ◽  
Vol 24 (6) ◽  
pp. 731-739 ◽  
Author(s):  
W L Stahl ◽  
S H Broderson
Keyword(s):  
Alkaline Phosphatase ◽  
Enzymatic Activity ◽  
Somatosensory Cortex ◽  
Adenosine Triphosphatase ◽  
Large Diameter ◽  
Cortical Layers ◽  
Outer Portion ◽  
Cacodylate Buffer ◽  
Neuronal Processes ◽  
Rat Somatosensory Cortex

Potassium-stimulated p-nitrophenylphosphatase (K+-pNPPase) activity was investigated in rat somatosensory cortex where 64-88% of enzymatic activity survived 5-10 min of fixation with 3% formaldehyde in 0.1 M cacodylate buffer, pH 7.4. Potassium-stimulated activity was inhibited by 1-10 mM ouabain. Levamisole (1.7 mM) inhibited brain alkaline phosphatase activity, facilitating the detection of K+-pNPPase activity. Strontium (10-20 mM) inhibited enzymatic activity by 38-75%. In parallel histochemical studies reaction product was found in strata, with cortical layers 2, 3, 4 and the outer portion of 5 containing the heaviest deposits. Highly reactive, vertically oriented, large diameter fibers were seen as groups between the outer portion of layer 5 and the pail surface. These fibers apparently arborize in the superficial layers. Smaller fibers were also positive and were oriented in various planes. The highest density of smaller, positive fibers occurred in layers 2 through 5. All positive fibers appeared to be axons or dendrites. Reaction product was not heavily concentrated in neuron perikarya or in glial elements. Sections did not contain reaction product when incubated in media lacking K+ or containing ouabain. The convergence of data from parallel histochemical and biochemical approaches supports the conclusion that the reactivity localized in the cerebral cortex represented the site of K+-pNPPase, a known component of the Na+,K+-adenosine triphosphatase complex. Neuronal processes demonstrated the highest enzymatic activity and may be most important in the active transport of Na+ and K+ in somatosensory cortex.

The Influence of Single VB Thalamocortical Impulses on Barrel Columns of Rabbit Somatosensory Cortex

2000 ◽  
Vol 83 (5) ◽  
pp. 2802-2813 ◽  
Author(s):  
Harvey A. Swadlow ◽  
Alexander G. Gusev
Keyword(s):  
Somatosensory Cortex ◽  
Rise Time ◽  
Action Potentials ◽  
Field Potentials ◽  
Cortical Layers ◽  
Axon Terminals ◽  
Inhibitory Mechanisms ◽  
Layer 4 ◽  
Slow Rise ◽  
A Minor

Extracellular recordings were obtained from single neurons in ventrobasal (VB) thalamus of awake rabbits while field potentials were recorded at various depths within topographically aligned and nonaligned barrel columns of somatosensory cortex (S1). Spike-triggered averages of cortical field potentials were obtained following action potentials in thalamic neurons. Action potentials in a VB neuron elicited a cortical response within layer 4 with three distinct components. 1) A biphasic, initially positive response (latency <1 ms) was interpreted to reflect activation of the VB axon terminals (the AxTP). This response was not affected by infusion of an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate receptor antagonist within the barrel. In contrast, later components of the response were completely eliminated and were interpreted to reflect focal synaptic potentials. 2) A negative potential [focal synaptic negativity (FSN)] occurred at a mean latency of 1.65 ms and lasted ∼4 ms. This response had a rapid rise time (∼0.7 ms) and was interpreted to reflect monosynaptic excitation. 3) The third component was a positive potential (the FSP), with a slow rise time and a half-amplitude duration of ∼30 ms. The FSP showed a weak reversal in superficial cortical layers and was interpreted to reflect di/polysynaptic inhibition. The amplitudes of the AxTP, the FSN, and the FSP reached a peak near layer 4 and were highly attenuated in both superficial and deep cortical layers. All components were attenuated or absent when the cortical electrode was missaligned from the thalamic electrode by a single cortical barrel. Deconvolution procedures revealed that the autocorrelogram of the presynaptic VB neuron had very little influence on either the amplitude or duration of the AxTP or the FSN, and only a minor influence (mean, 11%) on the amplitude of the FSP. We conclude that individual VB thalamic impulses entering a cortical barrel engage both monosynaptic excitatory and di/polysynaptic inhibitory mechanisms. Putative inhibitory interneurons of an S1 barrel receive a highly divergent/convergent monosynaptic input from the topographically aligned VB barreloid, and this results in sharp synchrony among these interneurons. We suggest that single-fiber access to disynaptic inhibition is facilitated by this sharp synchrony, and that the FSP reflects a consequent synchronous wave of feed-forward inhibition within the S1 barrel.

Cell dispersion patterns in different cortical regions studied with an X-inactivated transgenic marker

Development ◽  
1995 ◽  
Vol 121 (4) ◽  
pp. 1029-1039 ◽  
Author(s):  
S.S. Tan ◽  
B. Faulkner-Jones ◽  
S.J. Breen ◽  
M. Walsh ◽  
J.F. Bertram ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Somatosensory Cortex ◽  
Cortical Region ◽  
Field Region ◽  
Cortical Layers ◽  
Cell Dispersion ◽  
Dispersion Patterns ◽  
Radial Dispersion ◽  
Sizeable Fraction ◽  
Cortical Regions

Inactivation of the X-linked lacZ transgene provides a novel and powerful way of distinguishing between clonally related cellular populations in X inactivation mosaics. This ability to distinguish between clonal populations of cells in the mature cortex permits inferences to be made about cellular dispersion patterns during cortical development. The present study addresses the extent to which radial and tangential dispersion patterns contribute to different regions of the cerebral cortex by quantifying the extent of cellular mixing between clonally distinct cells in separate domains of the medial, dorsolateral and lateral cortices. We show that stripes running perpendicular to the cortical layers are more likely to be seen in the medial and dorsolateral regions, and that the appearance of a stripe is attributed to about two-thirds of the cells being of the same colour. Both neurons and glia appeared to exhibit the same ratio of cell mixing. In the lateral regions of the cortex, stripes were not apparent, and cell mixing was roughly equal. In the barrel-field region of the somatosensory cortex we looked for a correspondence between cytoarchitectural features and clonal borders but found no correlation. These results demonstrate, first, that although there is widespread radial dispersion, no cortical region is composed of radially arrayed stripes of cells in which all members of a stripe are derived from a single progenitor. Second, they demonstrate that, within regions containing a sizeable fraction of cells that do migrate radially, the boundaries of individual stripes do not always coincide with single anatomical units of cortical specialization, such as individual barrels.

scholarly journals Short- and long-latency somatosensory neuronal responses reveal selective brain injury and effect of hypothermia in global hypoxic ischemia

2012 ◽  
Vol 107 (4) ◽  
pp. 1164-1171 ◽  
Author(s):  
Dan Wu ◽  
Wei Xiong ◽  
Xiaofeng Jia ◽  
Romergryko G. Geocadin ◽  
Nitish V. Thakor
Keyword(s):  
Brain Injury ◽  
Somatosensory Cortex ◽  
Field Potential ◽  
Cortical Activity ◽  
Neuronal Responses ◽  
Early Recovery ◽  
Long Latency Responses ◽  
Long Latency ◽  
Hypoxic Ischemia ◽  
Somatosensory Neurons

Evoked potentials recorded from the somatosensory cortex have been shown to be an electrophysiological marker of brain injury in global hypoxic ischemia (HI). The evoked responses in somatosensory neurons carry information pertaining to signal from the ascending pathway in both the subcortical and cortical areas. In this study, origins of the subcortical and cortical signals are explored by decomposing the evoked neuronal activities into short- and long-latency responses (SLR and LLR), respectively. We evaluated the effect of therapeutic hypothermia on SLR and LLR during early recovery from cardiac arrest (CA)-induced HI in a rodent model. Twelve rats were subjected to CA, after which half of them were treated with hypothermia (32–34°C) and the rest were kept at normal temperature (36–37°C). Evoked neuronal activities from the primary somatosensory cortex, including multiunit activity (MUA) and local field potential (LFP), were continuously recorded during injury and early recovery. Results showed that upon initiation of injury, LLR disappeared first, followed by the disappearance of SLR, and after a period of isoelectric silence SLR reappeared prior to LLR. This suggests that cortical activity, which primarily underlies the LLR, may be more vulnerable to ischemic injury than SLR, which relates to subcortical activity. Hypothermia potentiated the SLR but suppressed the LLR by delaying its recovery after CA (hypothermia: 38.83 ± 5.86 min, normothermia: 23.33 ± 1.15 min; P < 0.05) and attenuating its amplitude, suggesting that hypothermia may selectively downregulate cortical activity as an approach to preserve the cerebral cortex. In summary, our study reveals the vulnerability of the somatosensory neural structures to global HI and the differential effects of hypothermia on these structures.

scholarly journals Encoding prediction signals during appetitive and aversive Pavlovian conditioning in the primate lateral hypothalamus

2019 ◽  
Vol 121 (2) ◽  
pp. 396-417 ◽  
Author(s):  
Atsushi Noritake ◽  
Kae Nakamura
Keyword(s):  
Negative Correlation ◽  
Lateral Hypothalamus ◽  
Environmental Changes ◽  
Behavioral Responses ◽  
Aversive Conditioning ◽  
Inhibitory Response ◽  
Appetite Regulation ◽  
Cynomolgus Monkeys ◽  
Specific Manner

The lateral hypothalamus (LH), which plays a role in homeostatic functions such as appetite regulation, is also linked to arousal and motivational behavior. However, little is known about how these components are encoded in the LH. Thus cynomolgus monkeys were conditioned with two distinct contexts, i.e., an appetitive context with available rewards and an aversive context with predicted air puffs. Different LH neuron groups encoded different degrees of expectation, predictability, and risks of rewards in a specific manner. A nearly equal number of one-third of the recorded LH neurons showed a positive or negative correlation between their response to visual conditioned stimuli (CS) that predicted the probabilistic delivery of rewards (0%, 50%, and 100%) and the associative values. For another one-third of recorded neurons, a nearly equal number showed a positive or negative correlation between their responses to rewards [appetitive unconditioned stimulus (US)] and reward predictability. Some neurons exhibited their highest or lowest trace-period responses in the 50% reward trials. These response modulations were represented independently and overlaid on a consistent excitatory or inhibitory response across the conditioning events. LH neurons also showed consistent responses in the aversive context. However, the responses to aversive conditioning events depending on the air puff value and predictability were less common. The multifaceted modulation of consistent activity related to outcome predictions may reflect motivational and arousal signals. Furthermore, it may underlie the role the LH plays in the integration and relay of signals to cortices for adaptive and goal-directed physiological and behavioral responses to environmental changes. NEW & NOTEWORTHY The lateral hypothalamus (LH) is implicated in motivational and arousal behavior; however, the detailed information carried by single LH neurons remains unclear. We demonstrate that primate LH neurons encode multiple combinations of signals concerning different degrees of expectation, appreciation, and uncertainty of rewards in consistent responses across conditioning events and between different contexts. This multifaceted modulation of activity may underlie the role of the LH as a critical node integrating motivational signals with arousal signals.

scholarly journals Cellular mechanisms for response heterogeneity among L2/3 pyramidal cells in whisker somatosensory cortex

2014 ◽  
Vol 112 (2) ◽  
pp. 233-248 ◽  
Author(s):  
Justin Elstrott ◽  
Kelly B. Clancy ◽  
Haani Jafri ◽  
Igor Akimenko ◽  
Daniel E. Feldman
Keyword(s):  
Somatosensory Cortex ◽  
Pyramidal Cells ◽  
Dendritic Morphology ◽  
Membrane Properties ◽  
Intrinsic Excitability ◽  
High Threshold ◽  
Cellular Mechanisms ◽  
Inhibitory Conductance

Whisker deflection evokes sparse, low-probability spiking among L2/3 pyramidal cells in rodent somatosensory cortex (S1), with spiking distributed nonuniformly between more and less responsive cells. The cellular and local circuit factors that determine whisker responsiveness across neurons are unclear. To identify these factors, we used two-photon calcium imaging and loose-seal recording to identify more and less responsive L2/3 neurons in S1 slices in vitro, during feedforward recruitment of the L2/3 network by L4 stimulation. We observed a broad gradient of spike recruitment thresholds within local L2/3 populations, with low- and high-threshold cells intermixed. This recruitment gradient was significantly correlated across different L4 stimulation sites, and between L4-evoked and whisker-evoked responses in vivo, indicating that a substantial component of responsiveness is independent of tuning to specific feedforward inputs. Low- and high-threshold L2/3 pyramidal cells differed in L4-evoked excitatory synaptic conductance and intrinsic excitability, including spike threshold and the likelihood of doublet spike bursts. A gradient of intrinsic excitability was observed across neurons. Cells that spiked most readily to L4 stimulation received the most synaptic excitation but had the lowest intrinsic excitability. Low- and high-threshold cells did not differ in dendritic morphology, passive membrane properties, or L4-evoked inhibitory conductance. Thus multiple gradients of physiological properties exist across L2/3 pyramidal cells, with excitatory synaptic input strength best predicting overall spiking responsiveness during network recruitment.

scholarly journals Neural Coding of Contact Events in Somatosensory Cortex

2019 ◽  
Vol 29 (11) ◽  
pp. 4613-4627 ◽  
Author(s):  
Thierri Callier ◽  
Aneesha K Suresh ◽  
Sliman J Bensmaia
Keyword(s):  
Somatosensory Cortex ◽  
Neural Coding ◽  
Discrimination Task ◽  
Object Manipulation ◽  
Spatiotemporal Dynamics ◽  
Population Response ◽  
Somatosensory Neurons ◽  
Amplitude Discrimination

Abstract Manual interactions with objects require precise and rapid feedback about contact events. These tactile signals are integrated with motor plans throughout the neuraxis to achieve dexterous object manipulation. To better understand the role of somatosensory cortex in interactions with objects, we measured, using chronically implanted arrays of electrodes, the responses of populations of somatosensory neurons to skin indentations designed to simulate the initiation, maintenance, and termination of contact with an object. First, we find that the responses of somatosensory neurons to contact onset and offset dwarf their responses to maintenance of contact. Second, we show that these responses rapidly and reliably encode features of the simulated contact events—their timing, location, and strength—and can account for the animals’ performance in an amplitude discrimination task. Third, we demonstrate that the spatiotemporal dynamics of the population response in cortex mirror those of the population response in the nerves. We conclude that the responses of populations of somatosensory neurons are well suited to encode contact transients and are consistent with a role of somatosensory cortex in signaling transitions between task subgoals.

scholarly journals The generation and propagation of the human alpha rhythm

2019 ◽  
Vol 116 (47) ◽  
pp. 23772-23782 ◽  
Author(s):  
Milan Halgren ◽  
István Ulbert ◽  
Hélène Bastuji ◽  
Dániel Fabó ◽  
Lorand Erőss ◽  
...  
Keyword(s):  
Somatosensory Cortex ◽  
Lower Order ◽  
Short Range ◽  
Alpha Rhythm ◽  
Higher Order ◽  
Cortical Layers ◽  
Posterior Cortex ◽  
Quiet Wakefulness ◽  
Occipital Pole ◽  
Thalamocortical System

The alpha rhythm is the longest-studied brain oscillation and has been theorized to play a key role in cognition. Still, its physiology is poorly understood. In this study, we used microelectrodes and macroelectrodes in surgical epilepsy patients to measure the intracortical and thalamic generators of the alpha rhythm during quiet wakefulness. We first found that alpha in both visual and somatosensory cortex propagates from higher-order to lower-order areas. In posterior cortex, alpha propagates from higher-order anterosuperior areas toward the occipital pole, whereas alpha in somatosensory cortex propagates from associative regions toward primary cortex. Several analyses suggest that this cortical alpha leads pulvinar alpha, complicating prevailing theories of a thalamic pacemaker. Finally, alpha is dominated by currents and firing in supragranular cortical layers. Together, these results suggest that the alpha rhythm likely reflects short-range supragranular feedback, which propagates from higher- to lower-order cortex and cortex to thalamus. These physiological insights suggest how alpha could mediate feedback throughout the thalamocortical system.

scholarly journals An invasive podosome-like structure promotes fusion pore formation during myoblast fusion

2010 ◽  
Vol 191 (5) ◽  
pp. 1013-1027 ◽  
Author(s):  
Kristin L. Sens ◽  
Shiliang Zhang ◽  
Peng Jin ◽  
Rui Duan ◽  
Guofeng Zhang ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Pore Formation ◽  
Actin Polymerization ◽  
Single Channel ◽  
Myoblast Fusion ◽  
Fusion Pore ◽  
Cellular Mechanisms ◽  
Cytoskeletal Remodeling ◽  
Specific Manner ◽  
Cell Type Specific

Recent studies in Drosophila have implicated actin cytoskeletal remodeling in myoblast fusion, but the cellular mechanisms underlying this process remain poorly understood. Here we show that actin polymerization occurs in an asymmetric and cell type–specific manner between a muscle founder cell and a fusion-competent myoblast (FCM). In the FCM, a dense F-actin–enriched focus forms at the site of fusion, whereas a thin sheath of F-actin is induced along the apposing founder cell membrane. The FCM-specific actin focus invades the apposing founder cell with multiple finger-like protrusions, leading to the formation of a single-channel macro fusion pore between the two muscle cells. Two actin nucleation–promoting factors of the Arp2/3 complex, WASP and Scar, are required for the formation of the F-actin foci, whereas WASP but not Scar promotes efficient foci invasion. Our studies uncover a novel invasive podosome-like structure (PLS) in a developing tissue and reveal a previously unrecognized function of PLSs in facilitating cell membrane juxtaposition and fusion.

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