The Nature Of Emotions In Humans

“Man is the only creature whose emotions are entangled with his memory”- Marjorie Holmes

Emotion is an overlap of three related responses: conscious feelings, overt behaviour and physiological responses. Overt behaviour includes posture and tone, whereas physiological responses include excessive perspiration and an increase in heart rate. Ekman (1992) highlighted that in humans, six basic emotional states are believed to exist: happiness, anger, disgust, fear, surprise and sadness. Each emotion is thought to have its own unique characteristics, allowing their expression in various circumstances. Emotion is a universal construct which is not only biologically determined but is also influenced by the environment. Cultural differences in emotion differ greatly, particularly in the area of emotional arousal. In western culture, high arousal emotions i. e. happiness are valued and encouraged more so than low arousal emotions i. e. sadness. Moreover, western culture experiences high arousal emotions at a superior degree than low arousal emotions. The opposite is true in eastern culture with a larger emphasis placed on low arousal emotion than high arousal emotion. Conversely individuals in the east prefer to experience low arousal emotion more than high arousal emotions. Gender differences in emotion also exist, with men far less likely to exhibit emotional states deemed as “feminine” such as sensitivity. Outward affectionate emotional display in public is also exhibited less in males. In essence emotion is a complex mixture of subconscious thoughts, outward displays and physiological responses.

Physiological adaptions to emotion are numerous. Most notable changes are tachycardia/bradycardia, piloerection, gastrointestinal motility, increased respiration and perspiration depending on the emotional state one finds themselves in. Emotion triggers the activation of all three components of the autonomic nervous system (ANS): sympathetic, parasympathetic and enteric nervous system. The ANS functions without voluntary control and innervates the activity of most tissues and organ systems within the body, making an essential contribution to homeostasis. In the case of sweating central thermosensitive neurons are situated in numerous structures in the brain, including the raphe nucleus, reticular formation and spinal cord. The hypothalamus maintains thermoregulation ensuring the body remains at 37 degrees Celsius. Sweat glands are innervated sympathetically by postganglionic nerve fibres, specifically sympathetic C fibres. Sweat production occurs following stimulation of postsynaptic M3 muscarinic receptors by acetylcholine. In cases of emotional sweating, possibly caused by emotionally affecting sensory information i. e. anxiety, regulation is at the level of the amygdala, insular cortex, prefrontal cortex and cingulum.

Stressful stimuli mainly effect sweat glands in the palms, the sole of the feet and the face and induces vasoconstriction in the vasomotor. Memory is the process by which knowledge is encoded, stored and later retrieved. Qualitatively various subcategories of memory exist mainly declarative and non-declarative memories. Declarative memories are long-term memories that involves conscious recollection, expressed through language which can be further divided into episodic memories-associated with time e. g. first day of school and semantic memories- involving factual knowledge, e. g. The capital of Ireland is Dublin. Episodic memory can be acquired in a single exposure, whereas semantic memory is strengthened by repetition but may also be acquired in a single exposure if sufficiently interesting. Declarative memory formation requires the hippocampus, adjacent cortex and of course conscious awareness. Non-declarative memories are not available to conscious recall and are linked with perceptual and motor skills. They are robust and formed along simple reflex pathwaysEmotion has a pivotal effect on memory.

Emotional states such as anger and disgust makes it easier for our subconscious to recall memories with the associated emotions generally due to the fact individuals rehearse these memories frequently as well as converse these vivid emotional memories with others. Remembrance of dramatic events are also easier recalled and encoded perhaps due to the interest and attention shown by the individuals when the event was ongoing e. g. 9/11. Evidently emotional arousal increases the strength of the memory and allows for far easier recall.