Abstract
This paper explains that the majority of people will experience hearing loss to greater or lesser extent as they get older because, with aging, the inner ear (cochlea) containing nerve cells, which convert sound into nervous impulses that are sent to the brain, don't work as well and eventually begin to degenerate. The author points out that most people do not go completely deaf and the severity of the hearing loss varies from person to person of the same age. The paper examines some research projects, whose apparent success might provide hope that one day hearing loss will no longer be associated with old age and can be reversed; another study describes the psychosocial consequences of hearing loss, which indicated that the majority of the people with presbyacusis did not report many quality of life distractions besides the inability to listen to the music. Glossary.

From the Paper
"Research was conducted by using senescence-accelerated mice (SAM) that develop progressive hearing loss at an early age. Mice were irradiated with 9Gy and later injected with 4x10 bone marrow cells from 2-month-old mice. After three months, the auditory brainstem response (ABR) was measured in order to evaluate the progress of hearing loss. It was noted that mice showed age-related hearing impairment above 2000Hz. After ABR and splenectomy five mice from experimental and control group were subject to further procedures, involving "intracardiac perfusion with saline followed by periodate-lysin-paraform aldehyde fixation and decalcification at 4 degrees C .in 5% buffered ethylene diaminetetra-acetate for seven days." The results showed that the immune system in mice was reconstituted by the donor cells and the age-related impairment of T-cell function is corrected. The age-related auditory response is also ameliorated after the manipulations."

Tags:brainstem-respone, mice, l-carnitine, assessment, unaware

Abstract
Amyotrophic Lateral Sclerosis (ALS) is a neuro-degenerative disorder producing deterioration of the motor cortex and motoneurons of the brainstem and spinal cord. In particular, patients are affected by the vulnerability of the cranial motoneurons that assist speech and swallowing. The disease usually leads to death in 3 to 5 years due to respiratory complications.

Tags:acoustics, perception speech

Abstract
In this article, the writer provides a discussion of rapid eye movement (REM) sleep, also known as paradoxical sleep. Several theories about the function of REM sleep are provided along with a discussion of the changes in the brain during REM sleep.

From the Paper
"As Wood Wood and Boyd maintain 'Many people who consider the field of psychology conjure up images of mental disorders and abnormal behavior'. Psychologists do study the strange and unusual but they are interested in the normal and commonplace as well. One phenomenon related to human beings that is within the category of the normal and commonplace is rapid eye movement sleep also known as paradoxical sleep. Discovered by Nathaniel Kleitman and Eugene Aserinsky, rapid eye movement sleep is the normal ..."

Tags:REM, dreams, Freud, Jung, memories, neurons, brainstem, waking, conscious, unconscious, mind, psychologists