Publications by authors named "Shimpei Ishiyama"

Ticklishness is an idiosyncratic form of touch observed in multiple animal species, including humans. Although commonly regarded as trivial, it involves complex neurobiological mechanisms and diverse behavioral phenomena observed across species. Two distinct forms exist: knismesis, a mild tingling sensation elicited by gentle touch, and gargalesis, an intense sensation associated with involuntary laughter.

View Article and Find Full Text PDF

Tickling is commonly perceived as juvenile play associated with laughter. However, its potential connection to adult sexual behavior has largely remained unexplored. Our online survey, primarily distributed among individuals interested in tickle fetishism, explored tickling and its association with sexual behavior.

View Article and Find Full Text PDF

Precise signal synchronization is vital for accurate analysis in systems neuroscience. Here, we present a protocol for synchronizing electrophysiology, videography, and audio recordings using a custom-made pulse generator. We describe steps for building the pulse generator, installing software, connecting devices, and running experimental sessions.

View Article and Find Full Text PDF

The cellular mechanisms of emotional contagion are unknown. We investigated tickle contagion and the underlying neuronal representations in playful rats. We recorded trunk somatosensory cortex activity of observer rats while they received tickling and audiovisual playback of tickling footage and while they witnessed tickling of demonstrator rats.

View Article and Find Full Text PDF

A tickle is a complex sensation: it occurs in response to touch but not unequivocally so, and makes us laugh albeit not when we self-tickle. We quantified human ticklishness by means of physiological, visual and acoustic measures alongside subjective reports, and assessed mechanisms of self-tickle suppression. Tickle responses arose faster than previously reported as changes in thoracic circumference and joyous facial expressions co-emerge approximately 300 ms after tickle onset and are followed by vocalizations starting after an additional 200 ms.

View Article and Find Full Text PDF

The relationship between tickling, sensation, and laughter is complex. Tickling or its mere anticipation makes us laugh, but not when we self-tickle. We previously showed rat somatosensory cortex drives tickling-evoked vocalizations and now investigated self-tickle suppression and tickle anticipation.

View Article and Find Full Text PDF

In a variety of cells, secretory processes require the activation of both Rab27a and L-type channels of the Ca(V)1.3 subtype. In the retinal pigment epithelium (RPE), Rab27a and Ca(V)1.

View Article and Find Full Text PDF

Munc13-3 is a presynaptic protein implicated in vesicle priming that is strongly expressed in cerebellar granule cells (GCs). Mice deficient of Munc13-3 (Munc13-3(-/-)) show an increased paired-pulse ratio (PPR), which led to the hypothesis that Munc13-3 increases the release probability (pr) of vesicles. In the present study, we analyzed unitary synaptic connections between GCs and basket cells in acute cerebellar slices from wild-type and Munc13-3(-/-) mice.

View Article and Find Full Text PDF

The coupling distance between presynaptic Ca(2+) influx and the sensor for vesicular transmitter release determines speed and reliability of synaptic transmission. Nanodomain coupling (<100 nm) favors fidelity and is employed by synapses specialized for escape reflexes and by inhibitory synapses involved in synchronizing fast network oscillations. Cortical glutamatergic synapses seem to forgo the benefits of tight coupling, yet quantitative detail is lacking.

View Article and Find Full Text PDF