Hearing ability

Baby babbling linked to hearing ability

The reason why the amount of vocalisations often differ between hearing and deaf infants is that vocalisations are primarily motivated by their ability to hear their own babbling, the findings showed.

The researchers also found that cochlear implants can help infants with profound hearing loss to correct their hearing. Cochlear implants are small electronic devices embedded into the bone behind the ear that replace some functions of the damaged inner ear.

“Hearing is a critical aspect of infants’ motivation to make early sounds,” said researcher Mary Fagan, an assistant professor at the University of Missouri in the US. This study shows babies are interested in speech-like sounds and that they increase their babbling when they can hear,” said Fagan.

Fagan studied the vocalisations of 27 hearing infants and 16 infants with profound hearing loss who were candidates for cochlear implants. She found that infants with profound hearing loss vocalised significantly less than hearing infants. However, when the infants with profound hearing loss received cochlear implants, the infants’ vocalisations increased to the same levels as their hearing peers within four months of receiving the implants.

“After the infants received their cochlear implants, the significant difference in overall vocalisation quantity was no longer evident,” Fagan said. “These findings support the importance of early hearing screenings and early cochlear implantation,” Fagan noted.

The study was published in the Journal of Experimental Child Psychology.

Source: the health site

Decline of hearing ability: Indian, US experts find gene role

Listening

In a path-breaking research which may have implications for those suffering from a decline of their cognitive and hearing abilities, Indian and American experts have established the role of a specific gene in triggering such conditions.

Experts of Sir Ganga Ram Hospital and University of Louisville School of Medicine stated that the MMP-9 gene plays a major role in causing decline of cognitive and hearing functions and removal of the said gene decreases
Hyperhomocysteinemia-induced cognitive and hearing dysfunctions.

Hyperhomocysteinaemia (HHcy) is a medical condition arising due to an abnormally high level of homocysteine in the blood, experts said.

“There is a role of MMP-9 in decline of cognitive and hearing functions. The ablation of MMP-9 decreases Hyperhomocysteinemia-induced cognition and hearing

dysfunction. This research was carried out on mice but has large implication for humans,” said Dr Seema Bhargava, lead author of the research and Senior Consultant, Department of Biochemistry, Sir Ganga Ram Hospital.

MMP-9 gene is a matrix metallopeptidase which helps in wound healing, cell migration, learning, memory and various other functions.

Currently, 45 per cent of adults in India between 45-92 years of age suffer from hearing impairment. Deficiency of Vitamin B-12 and folate (another form of vitamin) and high homocysteine levels have also been associated with impaired
hearing in women.

“It is important to identify individuals at risk for HHcy (e.g. elderly people)… To reduce homocysteine levels, adequate vitamin supplements should be given. However, if HHcy is already present, vitamins will take several months to reduce the concentration of homocysteine.

“Our study has advocated the role of MMP-9 inhibitors by pharmaceutical companies as a therapeutic option,” Bhargava said.
The research was published in the May edition of Journal of Molecular Biology Reports.

Source: Zee news