PSYC 304 American Military Week 2 Anatomy and Physiology of Hearing Discussion

Upon viewing the video on the Anatomy and Physiology of Hearing (the link can be found in Lessons – Week Two), describe the structure of the ear, focusing on the role that each component plays in transmitting the vibrations that enter the outer ear to the auditory receptors in the inner ear. Then, discuss the basic difference between determining the location of a sound source in the brain and determining the location of the visual object in the brain. Lastly, discuss the somewhat surprising outcome of research on hearing loss in urban versus rural environments, and the physiological explanation behind it. Support your belief and use specific examples.

https://youtube.com/watch?v=NET2xZ5zRXI%3Fwmode%3Dopaque%26rel%3D0

Minimum 300 words answer

Classmate #1:

Hello Class!

There are many structures of the ear that help us to hear. The first structure is the pinna, the outer part of the ear. Sound first passes through to the external auditory canal. The external auditory canal is like a tunnel or passageway that sound travels through to reach the ear drum.

The eardrum has a membrane that sound vibrates on when it reaches it. The vibrations cause the sound to travel to the bones of the middle ear.

There are three bones that make up the middle ear called, the malleus, incus, and stapes. They help to amplify the sound through the oval window into the cochlea.

The cochlea is part of the inner ear that has nerve impulses that respond to vibrations from sound. Inside of the cochlea is peri lymphatic fluid. This fluid turns vibrations into sound waves that causes it to cover the organ of corti. The surface of the organ of corti have hair cells that are neurons that are used to transmit information from sound into the brain

The part of the brain that is receives the sound information is the primary auditory cortex that is located in the temporal lobe. This part of the brain processes auditory language and speech comprehension (Temporal Lobe 2020). The information is then passed on to other parts of the brain such as the middle temporal gyrus that helps to understand, learn, and language.

When determining the source of a sound it is called sound localization, being able to understand what a sound is and where it originated from. The parts of the brain that processes sound localization is the posterior belt area and the anterior belt area.

Vision on the other hand is determined by the occipital lobe of the brain. This area helps process visual information by using neurons to encode incoming visual sensory information.

The difference between visual and sound source is determined by the parts of the brain that helps to identify the source. However, when these processes work together to identify the source and understand the information received it’s called sensory interaction.

In a recent study conducted by the Department of Otolaryngology of the Postgraduate Institute of Medical Education & Research, Chandigarh the comparison of hearing loss between urban and rural children; there were a 6.1% hearing loss in urban group and 32.8% in the rural group. This is explained by rural areas have are typically lower socioeconomical status leading to poorer hygiene and access to medical and health care services.

Hearing impairment has also been linked to mental health. There is an increased risk of developing anxiety, depression, and schizophrenia according to Stoll, McGrath 2017. This is in part due to difficulty hearing, responding appropriately in social situations, and feeling isolated due to hearing loss. Feelings of isolation lead to depression, substance abuse, and suicidal thoughts and actions.

Thank you for reading my post this week!

Joelle

Mann, S. & Sharma, S & Gupta, A & Nagarkar, Anu & Dharamvir,. (1998). Incidence of Hearing Impairment among Rural and Urban School Going Children : A Survey. Indian journal of pediatrics. 65. 141-5. 10.1007/BF02849707.

McGrath, L., Stoll, C. (October 10, 2107) Protecting Your Hearing Means Protecting Your Mental Health. Retrieved

https://hearinghealthfoundation.org/

blogs/protecti…

Temporal Lobe (2020) Science Direct. Retrieved from

https://www.sciencedirect.com/topics/medicine-and-…

Classmate #2:

Hello class,

I really enjoyed learning about the anatomy and physiology of hearing. The ear has many structures involved in hearing but it all starts with vibrations that create movement among air molecules. This creates a wave that is first detected by the outer folds of our ears called the pinna. The pinna catch the waves and amplify the sound, which then travels through the ear canal to the ear drum. The ear drum has a membrane known as the tympanic membrane, which vibrates when the waves of sound hit it. This vibrating causes the ear drum to move back and forth against three tiny bones within the inner ear. These bones are called malleus, incus, and stapes, and they amplify the sound and move it through to the oval window. In the oval window these vibrations become waves again and travel to the cochlea. In the cochlea there is fluid known as perilymphatic fluid. The sound waves create movement in this fluid which then moves across a surface called the organ of corti. The organ of corti contains hair like cells, or cilia, that are actually neurons. These neurons detect the type of sound wave, long slow waves create low frequency sounds and fast short waves create high frequency sounds. The cilia then send the message to the auditory cortex in the temporal lobe. From there it is sent to the middle temporal gyrus for decoding and understanding.

The visual center in the brain includes the thalamus, primary visual cortex, parietal lobe, and temporal lobe. The stimuli first reaches the thalamus where it is then routed to the primary visual cortex. From there it is sent to the parietal and temporal lobes for processing and understanding.

Rural communities have a higher rate of hearing loss than urban communities. Hearing loss is greater among poverty and manual labor careers which are both often seen in rural areas. One reason for this is those in rural communities are less likely to have easy access to hearing specialists and therefore have untreated hearing loss. A physiological explanation for this is the damage done to hearing by loud machinery. According to our book, prolonged exposure to loud sounds can lead to damage to the cilia resulting hearing loss.

Classmate #3:

Hello everyone,

For this week’s forum topic, we were asked to discuss the structures of the ear and focus on the role of components that plays a part in transmitting the vibrations that enter the ear to the auditory receptors within the inner ear. According to our lesson, sound starts as a distal stimulus. As the sound enters our outer ear of (pinnae), it travels through the auditory canal which lead to the tympanic membrane. Sound waves are vibrations which are caused by an object that changes the surrounding pressure of the air, water, or whatever other source that can transmit vibrations. Those vibrations, when meeting the tympanic membrane, cause it to vibrate.

The vibrations from the tympanic membrane are sent to the ossicles or the three inner bones of the middle ear. The ossicles consist of the malleus, the incus, and the stapes. First the vibrations are moved by the malleus and carried to a smaller channel called the incus, and finally, the vibrations are moved on to the stapes. From here, the vibration’s move into the oval window. As the vibrations travel through the semicircular canals, they move into the cochlea. The cochlear ganglion moves the vibration towards the basil membrane and organ of Corti where those same vibrations are turned into electricity. The electrical signal is sent towards the Cochlear nerve where they begin their travel further towards to cochlear nucleus and on into the brain. (

https://www.nidcd.nih.gov/

, 2018).

Secondly, we were asked to discuss the basic difference between determining where the location of a sound source is in the brain as compared to where a visual object source is in the brain.

The areas where the brain is responsible for sound location is the back of the cortex as well as in an area towards the front of the cortex. The “what” auditory pathway is an area that extends from what is called the anterior belt area to the frontal cortex. This is the pathway that is responsible for a person to understand what a sound is. The “where” auditory pathway is in an area called the posterior belt area to the frontal cortex. This pathway is responsible in letting the person know where the sound is coming from. (Goldstein & Brockmole, 2020).

The visual location of the brain is in the primary visual cortex which lies in the occipital lobe of both cerebral hemispheres. As information leaves the retina within the eyeball, it travels to the optic nerve where it becomes what is called the optic tract. This goes into the nucleus of the thalamus. From there, the information travels in what is referred to as the optic radiation that curves around the wall of the lateral ventricle in each hemisphere of the brain. The information finally arrives at occipital lobe where the information is processed. (www. psych.athabascau.ca, 2019).

And finally, were asked to discuss how hearing loss happens occurs in urban areas as compared to rural environments. A study performed by three departments from the University of Alabama in joint efforts with Department of Psychiatry, Rhode Island Hospitalfound that data collected from 71 participants with hearing loss and 45 without, showed that “adults with hearing loss living in rural areas, had poor perceived tangible support”. (

https://www.ncbi.nlm.nih.gov/

, 2018). Another study conducted with 1,670 school going children (urban 1030 and rural 640) all in the age range of 12- 14 years were screened for hearing loss. This survey was conducted by the Department of Otolaryngology of the Postgraduate Institute of Medical Education & Research, Chandigarh. (Mann, Gupta, 1998). This study, like the other, shows that those in rural areas do not have the support, i.e., medical, monetary, and social, which in turn can lead to hearing loss. Psychologically, this effect can be profound as hearing loss can bring the onset of “depression, schizophrenia, and dementia, and can trigger episodes of extreme anger and suicidal ideation”. (https://hearinghealthfoundation.org/, 2017).

Thanks, and hope everyone has a great week!

References

(n.d.). Retrieved January 13, 2020, from https://psych.athabascau.ca/html/Psych402/Biotutorials/24/part1.html.

Goldstein, E. B., Brockmole, J. R., Hooff, J. C. van, Caldara, R., & Richoz Anne-Raphaëlle. (2020). Psychologie cognitive. Andover: Cengage Learning EMEA.

Hay-McCutcheon, M. J., Hyams, A., Yang, X., & Parton, J. (2018, August). Hearing loss and social support in urban and rural communities. Retrieved January 13, 2020, from

https://www.ncbi.nlm.nih.gov/pubmed/29671659

.

Hearing Health Foundation. (2017, October 10). Protecting Your Hearing Means Protecting Your Mental Health. Retrieved January 13, 2020, from https://hearinghealthfoundation.org/blogs/protecting-your-hearing-means-protecting-your-mental-health.

How Do We Hear? (2018, January 3). Retrieved January 13, 2020, from

https://www.nidcd.nih.gov/health/how-do-we-hear

.

Mann, S.B.S., Sharma, S.C., Gupta, A.K. et al. Incidence of hearing impairment among rural and urban school going children: A survey. Indian J Pediatr 65, 141–145 (1998) doi:10.1007/BF02849707

Minimum 200 words answer to each