Sound changes the way rodents sense touch

December 28, 2018

Our eyes, ears and skin are responsible for different senses. Moreover, our brain assigns these senses to different regions: the visual cortex, auditory cortex and somatosensory cortex. However, it is clear that there are anatomical connections between these different cortices such that brain activation to one sense can influence brain activation to another. A new study by the laboratory of Associate Professor Shoji Komai at the Nara Institute of Science and Technology (NAIST), Japan, seen in PLOS ONE, explains how auditory stimulation of the barrel cortex influences responses to tactile stimulation in mice and rats.

The barrel cortex is one of the most highly studied primary somatosensory systems in animals, that is, systems in our brain sensitive to touch, pain, and temperature. It may not immediately be obvious why studying the barrel cortex, which maps sensation to whiskers, is relevant to humans, but it turns out the texture discrimination performed by the whiskers in rodents is quite similar to the same discrimination we do using our finger tips. Therefore, Komai considered the barrel cortex a good model to see how sound can affect the perception of touch.

"We think our senses are distinct, but there are many studies that show multisensory responses, mainly through audio-visual interactions or audio-tactile interactions," explains Komai.

Using patch clamp experiments of single neurons, his group found that mouse and rat neurons in the barrel cortex were unresponsive to light, but that a strong majority responded to sound. These neurons showed electrical responses to sound that could be categorized as regular spiking or fast spiking. Further, the barrel cortex appeared to treat tactile and auditory stimuli separately.

"These responses indicate that tactile and auditory information is processed in parallel in the barrel cortex," says Komai.

Additional analysis showed that the electrophysiological properties of the responses were different, with sound causing longer postsynaptic potentials with long latency, almost priming the animal to sense touch. This would be like the shuddering one does when hearing a loud boom. According to Komai, this reaction would be an evolutionary advantage for nocturnal animals such as rats and mice.

"In a nocturnal environment, sound may act as an alarm to detect prey or predators. The combination of auditory and tactile cues may yield an effective response. It will be interesting to learn how the same system is advantageous in humans," he says.
-end-
Resource

Title: Auditory-induced response in the primary sensory cortex of rodents

Authors: Atsuko T. Maruyama & Shoji Komai

Journal: PLOS ONE, 13, e0209266

DOI: 10.1371/journal.pone.0209266

Nara Institute of Science and Technology

Related Discrimination Articles from Brightsurf:

Muslims, atheists more likely to face religious discrimination in US
A new study led by the University of Washington found that Muslims and atheists in the United States are more likely than those of Christian faiths to experience religious discrimination.

Racial discrimination linked to suicide
New research findings from the University of Houston indicate that racial discrimination is so painful that it is linked to the ability to die by suicide, a presumed prerequisite for being able to take one's own life, and certain mental health tools - like reframing an incident - can help.

Perceived "whiteness" of Middle Eastern Americans correlates with discrimination
The perceived ''whiteness'' of Americans of Middle Eastern and North African descent is indirectly tied to discrimination against them, and may feed a ''negative cycle'' in which public awareness of discrimination leads to more discrimination, according to a Rutgers-led study.

When kids face discrimination, their mothers' health may suffer
A new study is the first to suggest that children's exposure to discrimination can harm their mothers' health.

Racial discrimination in mortgage market persistent over last four decades
A new Northwestern University analysis finds that racial disparities in the mortgage market suggest that discrimination in loan denial and cost has not declined much over the previous 30 to 40 years, yet discrimination in the housing market has decreased during the same time period.

Successful alcohol, drug recovery hampered by discrimination
Even after resolving a problem with alcohol and other drugs, adults in recovery report experiencing both minor or 'micro' forms of discrimination such as personal slights, and major or 'macro' discrimination such as violation of their personal rights.

Sexual minorities continue to face discrimination, despite increasing support
Despite increasing support for the rights of people in the LGBTQ+ community, discrimination remains a critical and ongoing issue for this population, according to researchers.

Fathers may protect their LGB kids from health effects of discrimination
Lesbian, gay, and bisexual individuals who report being discriminated against but who feel close to their fathers have lower levels of C-reactive protein -- a measure of inflammation and cardiovascular risk -- than those without support from their fathers, finds a new study from researchers at NYU College of Global Public Health.

Uncovering the roots of discrimination toward immigrants
Immigrants are often encouraged to assimilate into their new culture as a way of reducing conflict with their host societies, to appear less threatening to the culture and national identity of the host population.

Using artificial intelligence to detect discrimination
A new artificial intelligence (AI) tool for detecting unfair discrimination -- such as on the basis of race or gender -- has been created by researchers at Penn State and Columbia University.

Read More: Discrimination News and Discrimination Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.