Polygraph tests, also known as lie detector tests, rely on the precise measurement of physiological responses such as heart rate, breathing patterns, and skin conductivity to determine whether an individual is being truthful. However, the accuracy of these measurements can be significantly influenced by an individual’s physical condition at the time of the test. Temporary illnesses, such as colds, the flu, or respiratory infections, can lead to abnormal physiological responses, potentially skewing the test results.
In this article, we’ll explore how temporary illness can affect the accuracy of polygraph tests and why it’s essential for examiners to consider these conditions before proceeding with an examination.
Table of Contents
The Effects of Illness on Physiological Responses
When someone is ill, their body is under stress, and this stress can manifest in various physiological changes. These changes can interfere with the body’s normal responses, which are the key indicators used in polygraph testing to assess truthfulness or deception. Below are some ways in which temporary illness can affect the physiological markers measured during a polygraph exam:
- Elevated Heart Rate and Blood Pressure Common illnesses, such as colds or the flu, often cause elevated heart rates and higher blood pressure due to fever, dehydration, or general bodily discomfort. In a polygraph test, elevated heart rate is one of the primary physiological responses measured. A higher-than-usual heart rate caused by illness can lead to false readings, suggesting stress or deception when it may simply be a result of the individual’s physical condition.
- Irregular Breathing Patterns Respiratory infections or congestion from a cold can affect an individual’s breathing. Polygraph tests rely on stable, regular breathing patterns as a baseline. When an examinee is sick, their breathing may become irregular due to coughing, congestion, or difficulty breathing, which can result in unreliable test results. Irregular breathing, even when caused by illness, may be mistakenly interpreted as a sign of anxiety or deception during questioning.
- Fatigue and Physical Discomfort Illness often brings with it fatigue, muscle aches, and overall physical discomfort. These factors can make it difficult for an individual to focus during the polygraph test or remain seated and still for extended periods, both of which are essential for accurate results. Fatigue can also affect cognitive function, making it harder for the examinee to respond to questions with the same level of clarity and mental sharpness as they would when healthy. This physical and mental strain may alter their physiological responses in ways that could compromise the test’s validity.
- Fever and Dehydration A fever can cause fluctuations in the body’s core temperature, which can lead to increased sweating and rapid heart rate—both of which are physiological responses measured by a polygraph. Dehydration, often a side effect of fever or illness, can further affect the body’s systems by lowering blood pressure or causing dizziness. These changes can skew the baseline readings the polygraph examiner uses to determine an individual’s normal physiological state. Consequently, the test results may suggest deception when, in fact, the individual’s responses are simply reactions to their illness.
Why Accurate Baselines Are Essential in Polygraph Testing
A polygraph test begins with the establishment of a baseline—a set of physiological measurements taken while the individual answers basic, non-threatening questions. This baseline is used to compare against their physiological responses during the more critical parts of the test, such as when asked questions related to the matter being investigated.
When an individual is suffering from a temporary illness, their baseline readings may not reflect their normal physiological state. As a result, the examiner’s ability to identify deviations from the baseline—which are used to detect deception—becomes compromised. For instance, a higher heart rate or irregular breathing patterns caused by illness may be incorrectly interpreted as stress or anxiety, leading to false positive results.
The Role of Examiners in Identifying Illness-Related Issues
It is the responsibility of the polygraph examiner to assess whether an individual is physically fit to undergo the test. This includes evaluating whether the person is experiencing any temporary health conditions that could interfere with the accuracy of the examination. A skilled examiner will inquire about the examinee’s health before the test begins and may postpone the test if there is evidence of illness that could distort the results.
While the polygraph test is a valuable tool for assessing truthfulness, its accuracy depends on the examinee being in a stable physical and mental condition. Administering the test to someone who is temporarily ill may not yield reliable data and could lead to erroneous conclusions.
Temporary Illness: A Reason for Caution, Not Disqualification
It’s important to note that temporary illnesses do not permanently disqualify someone from taking a polygraph test. Once the individual has recovered from their illness, the test can be rescheduled to ensure that their physiological responses are not being affected by health-related factors. By waiting until the examinee is healthy, the polygraph examiner can establish an accurate baseline and more reliably assess the individual’s truthfulness.
In cases where the illness is short-term, such as a cold or flu, rescheduling the test for a later date after the person has fully recovered is often the most prudent course of action. This ensures that the results are accurate and based on the individual’s true physiological responses, free from the confounding effects of illness.
Conclusion
Temporary illness can significantly affect the accuracy of polygraph tests by altering the physiological responses measured during the examination. Illness-related symptoms like fever, fatigue, irregular breathing, and elevated heart rate can distort baseline readings, leading to false results. For this reason, it is essential for polygraph examiners to assess an individual’s health before proceeding with the test and, when necessary, reschedule the examination until the examinee has fully recovered.
By ensuring that polygraph tests are conducted when individuals are in a stable, healthy condition, examiners can uphold the accuracy and integrity of the testing process, ultimately delivering more reliable results.