Lie detectors are also called polygraphs because they graphically record several bodily reactions simultaneously which measure the bodily arousal of the individual. Typically a lie detector measures changes in blood pressure, heart-rate, breathing-rate and depth, and the Galvanic Skin Response (GSR) which indicates variations in the electrical conductivity of the skin.

The individual being tested is first asked a series of neutral (control) questions to establish the baseline. Simple questions are followed by specific questions that are designed to evoke responses from a guilty knowledge supposedly indicating the individual’s involvement in the crime being investigated. The lie detector or the polygraph records the changes in neurophysiological activities that occur while the suspected individual answers these questions.

Though the polygraph makes several objective recordings, the interpretation of these records relies heavily on the subjective judgement by the examiner. It is also probable that several unrelated factors like fear, pain or anxiety being felt by the individual during the test may affect her/his level of arousal. It is possible for the individual to lie with it. The validity of polygraph results in doubtful; however these are still used by law-enforcing agencies for lie detection.

Emotional intelligence: Expressions of emotion depend on regulation of emotion for self or others. Persons who are capable of having awareness of emotions for self or others and regulate accordingly are called emotionally intelligent. Persons who fail to do so, deviate and thereby develop abreaction of emotion, resulting in psychopathology of certain kinds.

By emotional intelligence we understand the ability of monitor one’s own and other’s emotions, to discriminate among them and to use the information to guide one’s thinking and actions (Mayer and Solovey, 1999). The concept of emotional intelligence subsumes intrapersonal and interpersonal elements. The intrapersonal element includes factors like self-awareness (ability to keep negative emotions and impulses under control), and self-motivation (the drive to achieve despite setbacks, developing skills to attain targets and taking initiative to act on opportunities). The interpersonal elements of emotional intelligence include two components: social awareness (the awareness and the tendency to appreciate other’s feelings) and social competence (social skills that help to adjust with others, such as team buildings, conflict management, skills of communicating, etc.)

Physiology of emotion: The nervous system, central as well as peripheral, plays a vital role in the regulation of emotion.

(i) Thalamus: It is composed of a group of nerve cells and act as a relay centre of sensory nerves. Stimulation of thalamus produces fear, anxiety, and autonomic reactions. A theory of emotion given by Cannon and Bard (1931) emphasises the role of thalamus in mediating and initiating all emotional experiences.

(ii) Hypothalamus: It is considered the primary center for regulation of emotion. It also regulates the homoeostatic balance, controls autonomic activity and secretion of endocrine glands, and organises the somatic pattern of emotional behaviour.

(iii) Limbic System: Along with thalamus and hypothalamus the limbic system plays a vital role in regulation of emotion. Amygdala is a part of limbic system, responsible for emotional control and involves formation of emotional memories.

(iv) Cortex: Cortex is intimately involved in emotions. However, its hemispheres have a contrasting role to play. The left frontal cortex is associated with positive feelings whereas the right frontal cortex with negative feelings.

Learning plays an important role in emotions. This happens in two ways. First, cultural learning influences the expression of emotions more than what is experienced.

For example, some cultures encourage free emotional expression, whereas other cultures teach people, through modeling and reinforcement, to reveal little of their emotions in public.

Second, learning has a great deal to do with the stimuli that produce emotional reactions. It has been shown that individuals with excessive fears (phobia) of elevators, automobiles, and the like learnt these fears through modeling, classical conditioning or avoidance conditioning.

A.

behaviour