Chapter 4 - Alternative Access

Question 1

Selection Set

Answer 1

• this refers to what symbols you have to choose from and how they are presented

Question 2

Selection Set

A. Components of the Selection Set (3)`

Answer 2

1. Messages
2. Symbols and Codes.
3. Operational or Interactional Commands (e.g. turn the page over, etc.)

Question 3

Selection Set

B. Physical Characteristics of Selection Set Displays

Answer 3

1. Number of items in the selection set - Encoding strategies are used to reduce the number of items in the selection set that are used. The number of items in the selection set depends on the number of codes used. If you combine the items to make a large number of codes, then fewer items are needed in the selection set.
2. Size
3. Spacing and Arrangement of Items
4. Orientation of display

Question 4

Selection Set

B. Physical Characteristics of Selection Set Displays –> Orientation of display

Answer 4

(1) mounting it on a table or wheelchair tray that is horizontal to the floor (see page 91). Advantages are that it provides supports for the persons arm and hand. Works well if there are tremors, like in Parkinson’s disease. But the person has to sit upright to use it. Neck also has to be bent to see.
(2) putting the display at a 30 or 45 ° angle to the floor. Advantage - it is easily seen but you don’t have to bend your neck down to look like with the horizontal display and it still gives some support for the arm. Disadvantage - it does not provide enough support for some people with really weak muscles. Also people with body movements that are uncontrollable have problems with this orientation.
(3) Orient the display at a 45 - 90° angle to the floor. Easier to see by may obstruct vision.

Question 5

Selection Set

C. Types of Displays (4)

Answer 5

1. Fixed displays (e.g. Go Talk, have to manually change picture)
2. Dynamic displays (like dinavox)
3. Hybrid Displays
4. Visual Scene Displays

Question 6

Selection (or access) Techniques –Direct access/selection or Scanning

A. Direct access or selection

Answer 6

1. Using physical pressure to depress a key or pad.
2. Physical contact such as in using a touch screen - no pressure is required.
3. Pointing - no physical contact used - eye pointing (gaze) (head pointer)
4. Voice Recognition - with high tech devices that have been programmed to recognize certain commands or codes.

Question 7

Selection (or access) Techniques –Direct access/selection or Scanning

B. Scanning – Used when direct selection is not an option.

Answer 7

1. Circular scanning technique - acts like a clock with symbols displayed in a circular pattern like numbers on a clock.
2. Linear Scanning Technique - linear means in a line. Page 99.
3. Group Item Scanning - in this type of scanning you are trying to identify the particular group of items.
4. Group row-column scanning is one type.
5. Scanning Time and Speed

Question 8

Selection (or access) Techniques –Direct access/selection or Scanning

B. Scanning – Used when direct selection is not an option.

Circular scanning technique –>

Answer 8

• acts like a clock with symbols displayed in a circular pattern like numbers on a clock.

Question 9

Selection (or access) Techniques –Direct access/selection or Scanning

B. Scanning – Used when direct selection is not an option.

Linear Scanning Technique

Answer 9

• linear means in a line. Page 99.

Question 10

Selection (or access) Techniques –Direct access/selection or Scanning

B. Scanning – Used when direct selection is not an option.

Group Item Scanning

Answer 10

• in this type of scanning you are trying to identify the particular group of items.

Question 11

Selection (or access) Techniques –Direct access/selection or Scanning

B. Scanning – Used when direct selection is not an option.

Group row

Answer 11

-column scanning is one type.

Question 12

Message output and input:

Output–>

Answer 12

Message Output - information that is sent by the AAC user. It can be synthetic speech, gestures, vocalizations, etc.

Question 13

Message output and input:

Input–>

Answer 13

Message Input - Information we give to the user, usually it is normal speech but it can be in written form, gestures, manual signs and vocalizations too.

Question 14

Types of Synthesized Speech (3):

Answer 14

1. Text to speech – already recorded into the device
2. Digitized speech - you record the human voice and store it, then reproduce it. It is usually faster to program. But it requires a lot of memory –> voice banking
3. Combination

Question 15

Types of Synthesized Speech:

Text to speech types (5)

Answer 15

1) DecTalk
2) VeriVox
3) AT&T
4) DynaVox
5) Vanguard

Question 16

Types of Synthesized Speech:

Digitized speech types (2):

Answer 16

1) MessageMate

2) AlphaTalker

Question 17

Intelligibility and Comprehensibility of Synthesized Speech

Factors Affecting Intelligibility of Speech in AAC devices:

Answer 17

1) Rate of speech - Slower than normal rate of synthesized speech aids understanding
2) Output methods - Word method is most easily understood.
3) Noise - has a worse effect on DECtalk than on natural speech.
4) Nonnative speakers of English - in noise, nonnative English speakers had more trouble transcribing sentences made with DECtalk.
5) Older adults with hearing loss have trouble with synthetic speech.
6) Practice - practice helps listeners to understand synthetic speech.
7) Synthetic speech via telephone - hard to understand sometimes

Question 18

Advantages of Synthesized Speech (5):

Answer 18

1) May reduce the partner’s burden in the interaction because all he has to do is understand spoken language, not signs, etc.
2) Gives information in a way that is familiar
3) Allows communication if a partner can’t read or has visual impairments
4) Allows the user to send message without first getting the partner’s attention
5) Allows communication to occur at a distance

Question 19

Disadvantages of Synthesized Speech (4):

Answer 19

1) even when synthesized speech is good it may be hard to understand in noise
2) difficult for nonnative speakers
3) difficult for those with hearing problems
4) difficult for perceptual problems such as aphasia