Hearing is the ability to detect sounds in everyday life and listening is the ability to interpret them – e.g. follow conversations in a noisy environment.
Loudness (intensity+ This is often measured in terms of hearing level (dB HL) – louder sound, higher number) and pitch (frequency+ Frequency is measured in kilohertz (kHz) – higher pitch, higher number) are two basic properties of sound. People with a hearing loss might experience difficulties
Any reduced sensitivity to sound can have a negative impact on quality of life. Click here for an example
Audiometry tests hearing acuity. It measures sensitivity to pitch and loudness under specified conditions. The test produces an audiogram. The audiogram compares an individual’s hearing sensitivity to a reference standard of ‘average hearing’. The audiogram does not define whether an individual will benefit from a specific intervention. A Hearing Care Professional needs to record history and symptoms, perform audiometry and other tests before it is possible to understand an individual’s hearing ability and address their communication needs.
Hearing loss can be
Sensorineural and conductive are the names given to the two main types of hearing loss
People that have a sensorineural and conductive hearing loss are said to have mixed hearing loss.
An audiogram – the results of a test usually performed by a hearing specialist – can be used to classify whether somebody has sensorineural, conductive or mixed hearing loss. The hearing specialist can also assess the ear using other tests – e.g. tympanometry and otoscopy – to help confirm the type and cause of hearing loss, and decide whether a referral to a medical colleague is required.
Disorders of central auditory processing, also known as auditory processing disorder (APD), can result in hearing difficulties. In these cases the audiogram is normal but individuals might complain about not being able to hear clearly. Prevalence data for APD is both variable and scarce*For example the Canadian Interorganizational Steering Group for Speech-Language Pathology and Audiology “Prevalence rates of auditory processing disorder in both children and adults have been difficult to confirm, and reports in the literature are inconsistent. Intuitively, prevalence rates should differ across age of the population; overall, the research suggests that audiometry process disorder is relatively infrequent in children and young adults, but quiet common in adults with brain injuries, (for example, with traumatic brain injury in veterans), and very common in seniors”. Ref: Canadian Interorganizational Steering Group for Speech-Language Pathology and Audiology 2012. Canadian Guidelines on auditory processing disorder in children and adults: assessment and intervention. It is estimated that 0.5% to 1% of the population have APD, with a higher prevalence in children – e.g. some estimates suggest a prevalence of between 2% and 7% in children4. One research project from the UK reported that APD might make up 5.1% of the caseload in children’s audiology, but just 0.9% of the caseload in adult clinics5.