Information Technology Reference
In-Depth Information
-
For diagnosing stress we use finger temperature sensor signals. By analyzing
this biomedical signal we identified large individual variations which make it
difficult to define in a model or use a set of rules. Other AI systems such as,
rule-based reasoning or model based reasoning is not appropriate in this con-
text. CBR can be used when there are no sets of rules or a model [14].
-
To implement a CBR system in this domain we need to identify features from
the finger temperature sensor signal which would allow a clinician to identify
features for the success or failure of a case. This would help to reduce the repe-
tition of mistakes in the future.
-
The knowledge in the domain is growing with time so it is important that the
system can adapt and learn new knowledge. Many of the AI systems failed to
continue because of the lack of this type of maintenance. CBR system can
learn by adding new cases into the case base.
-
The cases in the case base can be used for the follow up of treatment and also
for training less experienced clinicians.
2 Background and Methods
2.1 Stress
The term 'stress' was first introduced by Hans Selye in the 1950s who noticed that
patients suffer physically not only as a result of a disease or medical condition. He
defined stress as a "non-specific response of the body to any demand" [15]. Stress is
our body's response to any threat to defend it from potential harm. Another definition
of stress by Lazarus is "stress occurs when an individual perceives that the demands
of an external situation are beyond his or her perceived ability to cope with them"
[16]. An individual's response to a situation/thing can be varied and depends on one's
coping capability. For example, a person might take a huge workload without being
worried and the same amount of work could make another person worried thinking
how to cope with that situation. So, an individual's mental state and ability to appraise
the stimulus determines whether stress occurs or not. In our everyday life we react to
certain events or facts that may produce stress. Our body's nervous system activates
and stress hormones are released to protect us. This is called the “fight-or-flight”
reaction, or the stress response.
The human nervous system is divided into two main parts, the voluntary system
and autonomic system. The automatic nervous system is divided into two parts: sym-
pathetic and the parasympathetic nervous system. The sympathetic nervous system
(SNS) works to protect our body against threats by stimulating the necessary glands
(i.e. thyroid and adrenal glands) and organs. It decreases the blood flow to the diges-
tive and eliminative organs (i.e. the intestine, liver, kidney etc.) and enhances the flow
of blood to the brain and muscles. The thyroid and adrenal glands also supply extra
energy. As a result it speeds up the heart rate, increases blood pressure, decreases
digestion and constricts the blood vessels i.e. vasoconstriction which slows down the
flow of blood etc. The SNS thus activates the body for the fight-or-flight response to
stress. The parasympathetic nervous system counteracts the fight-or-flight response to
Search WWH ::
Custom Search