Methods and apparatus for modifying a user interface as a function of the
detected emotional state of a system user are described. In one
embodiment, stress analysis is performed on received speech to generate
an emotional state indicator value, e.g., a stress level indicator value.
The stress level indicator value is compared to one or more thresholds.
If a first threshold is exceeded the user interface is modified, e.g.,
the presentation rate of speech is slowed. If a second threshold is not
exceeded, another modification to the user interface is made, e.g., the
speech presentation rate is accelerated. If the stress level indicator
value is between first and second thresholds, user interface operation
continues unchanged. The user interface modification techniques of the
present invention may be used in combination with known knowledge or
expertise based user interface adaptation features.