Speech processor

Artificial ear implants capable of processing speech have been developed with electrodes to stimulate cochlear nerve cells. Cochlear implants also have a speech processor that transforms sound waves into electrical impulses that can be conducted through coupled external and internal coils. The electrical impulses can be transmitted directly by means of a percutaneous device. 

Blarney, Rj. and Clark, G.M. 1985. A wearable multiple-electrode electrotactile speech processor for the profoundly deaf. /. Acoust. Soc. Am. 77 1619. 

Cochlear implants can be divided into two components the external speech processor and the implanted electrode array and electronics. A diagram of a cochlear implant is shown in Figure 40.1. Sounds recorded by the microphone are sent to the speech processor, which decomposes the incoming waveform and extracts certain cues that allow the speech signal to be represented as a pulse sequence. The information about the pulse sequence is then transmitted transcutaneously to the implanted electronics through a radio-frequency link, where it is decoded and used to specify stimuli that are delivered via the implanted electrode array. 

FIGURE 40.1 Diagram of cochlear implant showing external speech processor and transmitter and internal receiver/stimulator and electrode array. (From Medical illustrations by NIH, Medical Arts Photography Branch.)... 

Cochlear Implants. The U.S. Food and Drug Administration approved cochlear implants in the mid-1980 s. A cochlear implant differs from a hearing aid in its structure and its function. It consists of a microphone that collects sound, a speech processor that sorts the incoming sound, a transmitter that relays the digital data, a receiver/stimulator that converts the sound into electrical impulses, and an electrode array that sends the impulses from the stimulator... 

Some companies offer patch cords that connect the speech processors of cochlear implants to assistive listening devices for improved effect Such patch cords make it easier to use cell phones and enjoy music on MP3 players. They are available with and without volume controls. 

Cochlear Implants. Cochlear implants (Cl), by fer the most successful sensory neural prostheses to date, have penetrated the mainstream therapeutic arsenal. Their popularity is rivaled only by the cardiac pacemakers and deep brain stimulation (DBS) systems. Implanted in patients with sensorineural deafness, these devices process sounds electronically and transmit stimuli to the cochlea. A Cl includes several components a microphone, a small speech processor that transforms sounds into a signal suitable for auditory neurons, a transmitter to relay the signal to the cochlea, a receiver that picks up the transmitted signal, and an electrode array implanted in the cochlea. Individual results vary, but achieving a high degree of accuracy in speech perception is possible, as is the development of language skills. 

Chapter 76 through Chapter 78 look toward the human and focus on measurement of performance capacities of specific groups of human subsystem and related issues. Due to a combination of the complexity of the human system (even when viewed as a collection of rather high-level subsystems) and limited space available, treatment is not comprehensive. For example, measurement of sensory performance capacities (e.g., tactile, visual, auditory) is not included. Both systems and tasks can be viewed at various hierarchical levels. Chapter 76 and Chapter 77 focus on a rather low systems level and discuss basic functional units such as actuator, processor, and memory systems. Chapter 78 moves to a more intermediate level where speech, postural control, gait, and hand-eye coordination systems could be considered. Measurement of structural parameters, which play important roles in both performance measurement and many analyses, is also not allocated the separate chapter it deserves (as a minimum) due to space limitations. Chapter 79 and Chapter 80 then shift focus to consider the analysis of different types of tasks in a similar, representative fashion. 

Speech emotion estimation module Estimates emotion in speech. This and the previous module examine the estimated emotion by using the emotion processor. 

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