25th October 2023

Emotion, Stress and Arousal

Emotion

The emotional response

The common-sense view of emotion sees it as something internal, distinct, and recognisable that occurs as an automatic response to specific ‘triggers’. An event occurs, and this causes a rapid emotional experience, which in turn triggers a physical response. The common-sense theory of emotion describes each emotional response as having three distinct parts:

• Subjective experience of emotion.
• Physiological changes in response to emotion.
• Associated skeletal muscle actions such as smiling, crying, running, etc…

Many psychologists believe that emotions have common elements across cultures and can be observed objectively and labelled via associated bodily reactions. Evolutionary psychologists were some of the earliest people attempting to describe emotion, and they stated that emotion helped fulfil biological needs and could be described as involuntary, fast-onset physiological phenomena linked to the automatic appraisal of a situation. Classical, evolutionary, and common-sense views of emotion have many common elements, whilst the most oppositional stance of emotion to these models was the James-Lange theory of emotion.

James-Lange and Cannon-Bard theories

The James-Lange theory of emotion says, ‘Emotion is not directly caused by the perception of an event, but rather by the bodily response caused by the event.’

For example – Running from a bear produces the emotion of fear secondary to the act of running away. The theory implies altering behaviour (specifically skeletal muscle behaviour) alters emotions. However, Walter Cannon, another psychologist (who developed the Cannon-Bard theory of emotion that says we experience physiological arousal and emotion simultaneously), criticised the James Lange theory of emotion by pointing out:

• Physiological arousal is often experienced without associated emotion, i.e., running causes physiological arousal but does not produce subsequent changes in emotion. 
• Physiological reactions happen too slowly to cause experiences of emotion. For example, intense fear can immediately follow hearing screams, but heart rate / skeletal muscle responses can be shown to lag behind the emotional response.

Human studies where subjects were injected with adrenaline and did not experience emotional response corresponding to arousal were able to discredit the James-Lange theory and provide evidence to support the Cannon-Bard position that the experience of an emotion does not depend on input from the body but that emotions and the physiological response to emotions are simultaneous and independent of each other.

Cognitive appraisal and primary emotions

Stanley Schachter and Jerome Singer are associated with the cognitive appraisal theory of emotion that says people’s experience of emotion depends on both the physiological arousal and subsequent cognitive interpretation of the arousal. They acknowledged that the emotional response is influenced by physiological responses but believed that interpretation of a person’s current context (environmental factors) and cognitive appraisal of a physical response was crucial to deciding what emotion was experienced. 

This theory incorporated aspects of the James-Lange theory (people infer emotions when they experience physiological arousal) and the Cannon-Bard theory (the same pattern of physiological arousal causes different emotions). The cognitive appraisal theory stresses the importance of conscious interpretation prior to determining the emotional response.

Richard Lazarus added to cognitive appraisal theories of emotion by looking at how emotions result via interactions between the person and their environment. Lazarus described two distinct aspects of cognitive appraisal.

Primary appraisal – Is an event benign or harmful to personal well-being?

Secondary appraisal – Does a person have the resources necessary to cope with the event?

The main function of the secondary appraisal is to determine an appropriate response or coping strategy by evaluating one’s available resources. For example, coping strategies help regulate emotions or help by changing the situation causing the emotion. Lazarus’ ideas were prescient of more modern concepts of ‘emotional regulation.’

Paul Ekman theorised that emotions were developed cross-culturally and universally. He undertook research in Papua New Guinea that supported his theory that certain emotions were ‘universal’ or ‘basic’ and distinguishable by facial expressions. These were:

• Anger.
• Disgust.
• Happiness.
• Sadness.
• Fear.
• Surprise.

Ekman theorised that the above were innate to humans as a species and played an essential role in survival.

Robert Plutchik also attempted to specify a list of universally experienced emotions. He developed eight basic emotions that he synthesised into the Plutchik Model, pictorially representing emotions on a wheel.

Plutchik theorised there were eight basic emotions, with some acting as ‘opposites’:

• Joy & Sadness.
• Anticipation & Surprise.
• Disgust & Trust.
• Fear & Anger.

Robert Plutchik also developed two categories of emotions: fundamental & non-fundamental.

He classified fundamental emotions as the eight basic emotions above and said that many non-fundamental emotions combined with the basic emotions could create individual/unique experiences of emotion.

Emotions and performance

Psychologists have long studied emotions and their impact on sporting and cognitive tasks. The specific effect of an emotional response depends on the context, the nature of the task, and the emotional response in question.

‘Positive’ emotions and emotional arousal can increase performance when appropriate to the situation and at an optimal level. However, high emotional arousal can impair performance if associated with excessive autonomic arousal. Negative emotions can impair cognition, executive function, and attention, and physical symptoms of anxiety can impair performance in even simple manual tasks.

Understanding emotional responses and taking steps to modulate them can help people perform better and understand how to optimise their emotional response for any given task.

Stress

Hans Selye defined stress as the ‘Non-specific response of the body to any demand placed upon it.’ 

Stress can be considered as both the psychological and physiological response to any actual or imagined life challenge. Stress can be positive or negative in its consequences for a person, and the terms ‘eustress‘, or positive stress and ‘distress’, or negative stress, were used by Selye to express this concept.

Eustress is the type of stress seen as manageable, productive, or even pleasurable. Distress is associated with overwhelming demands and can degrade mental and physical health. Gastrointestinal problems, cardiovascular disease, respiratory and a wide range of autoimmune conditions can all be evidenced as exacerbated by distress. Stress can cause uncomfortable physical symptoms itself, such as the fight or flight response mediated by the amygdala, hypothalamus, and adrenal glands. Stress can induce psychological reactions such as anxiety, anger, depression, and cognitive impairment. Shelley Taylor described four different routes by which stress can affect health:

• Direct route.
• Interactive route (also known as the stress-vulnerability model).
• Health behaviour route.
• Illness behaviour route.

Feeling that a stressful event is predictable or within control has been shown to decrease the level of distress caused. However, even if a stressor is well within a person’s resources to manage, if it challenges our core beliefs, it can cause significant distress. Objective external physical dangers can cause stress, or stress can be entirely internal and mental and generate negative emotions via an internal psychological conflict. In psychological terms, conflict is when two or more strong conscious or unconscious motives cannot be solved together.

Resilience and vulnerability

Vulnerability and lack of resilience are terms that are often used interchangeably; however, in psychological terms, these can be defined more precisely: 

Resilience – The psychological process developed in response to life stressors that facilitates healthy functioning.

Vulnerability – Inability to withstand the effects of a hostile environment.

Vulnerability is a negative predictor of mental and physical health conditions and is correlated with a negative effect and low life satisfaction, whilst the opposite is true for resilience or psychological invulnerability.

The most interesting example of the above can be illustrated by the studies of Norman Garmezy, who published studies looking at the prognosis of patients diagnosed with schizophrenia. Garmezy noted that some patients with schizophrenia suffered remarkably poor long-term function following a psychotic episode, whilst others ‘recovered’ well and went on to re-establish previous employment and relationships. Garmezy wrote that those patients who recovered well had ‘A pattern of competency across different aspects of life and function.’

Further studies into children from high-risk socioeconomic classes who experienced early years trauma showed that many children demonstrated competence in relationship maintenance, academic achievement, and healthy life progression. He named these children ‘invulnerable.’ By analysing these children’s outcomes, ideas about protective factors enabling resilience were developed.

Factors proposed to enhance resilience:

• Autonomy.
• High self-esteem.
• Intelligence.
• Social skills.
• Social support outside the family.
• Warmth of family relationships.

Type A theory

The Type A theory, although largely considered to pertain to aspects of personality, has great significance with regard to stress and its impact on health. Originating from observations of patients by two cardiologists, Friedman and Rosenman. Type A theory describes type A people as high-achieving individuals who are easily aroused, prone to hostility, have exaggerated time urgency and impatience, and are highly organised and ambitious. Individuals who lacked these prominent characteristics were Type B people. Type A people were initially proposed to be at greater risk of heart disease as their need for control over their environment made them less resilient to external and internal stress. Although this idea has since been disputed, the rough consensus is that Type A people, whilst generally predisposed to high achievement, are also generally predisposed to be psychologically vulnerable to adverse impacts of stress.

Coping mechanisms

Coping strategies are behaviours or thought patterns people engage in to mitigate or relieve stress. Several types of coping mechanisms have been defined, such as:

• Appraisal-focused.
• Emotion-focused.
• Problem-focused.

These can further be subdivided into adaptive and maladaptive coping mechanisms.

Lazarus identified cognitive appraisal as a way of determining whether a stressor was such that an individual’s resources could adequately deal with it or it would overwhelm them. Appraisal-based coping techniques use this model to help individuals reframe their appraisal of their ability to cope with a stressor more positively. Positive appraisal style, or the tendency to appraise potentially threatening situations positively, is a vital resilience tool used in positive cognitive reappraisal-based therapies. 

Emotion-focused strategies diminish negative feelings generated by stress, while problem-focused techniques diminish stress by working to correct or eliminate the source of the stressor.

Adaptive coping mechanisms help a person develop resilience to stress, while maladaptive coping strategies are unhealthy, unproductive, and harmful. Maladaptive coping mechanisms such as rumination, isolation or overeating may provide temporary relief, but the longer term can exacerbate stress.

Locus of control and learned helplessness

The locus of control can be considered part of personality and is a person’s perception of where control lies and what the causes of their life experiences are. An internal locus of control is when people view their actions as controlling their fate. An external locus of control is when someone attributes their fate to outside influences. Generally, maintaining an internal locus of control is considered a more psychologically protective process, although most people switch between different loci of control at different times.

Martin Seligman developed the concept of learned helplessness via experimentation on dogs. A group of dogs were given a series of electric shocks that they could not escape and, in turn, developed a conditioned feeling of helplessness. When the dogs were put in a new environment where they could escape electric shocks, they did not attempt to, as they had accepted their situation and ‘learned helplessness’. When a person or animal learns to endure adverse events and does not try to avoid these, even when able to, they are said to demonstrate learned helplessness. 

Arousal

Awareness and consciousness

Consciousness and awareness are often erroneously used as synonyms, partly due to both having varying levels. Awareness is a relative concept often described as a state of cognisance of oneself and one’s environment. Consciousness is an objectively measured state in which one is awake and aware. 

Full consciousness is a state of optimal waking awareness, and reduced consciousness can be produced by physiological or pathological processes, i.e. sleep or a head injury. Full consciousness is when a person can perceive and interact with the external world appropriately; altered states of consciousness are when a person’s sense perceptions or ability to respond to external stimuli are diminished. Consciousness can be measured via the Glasgow coma scale, which scores motor, verbal, and eye responsiveness to stimulus. Consciousness is only a small part of neural and psychological activity. Many brain activities are unconscious, i.e. visual analysis of depth perception or reflex motor activity, or regulation of hormones and biorhythms.

Unconscious processes are now understood to underlie many cognitive functions previously thought to be fully conscious processes. The unconscious processing of emotional information has long been a critical part of psychoanalytic psychology but is now a concept also endorsed by cognitive neuroscience, as functional imaging studies have established that the right hemisphere subcortical pathway is implicated in emotional processing. 

Arousal, attention, and alertness

Arousal, attention, and alertness are overlapping constructs.

Arousal in psychology is defined as the sensation of being alert and awake. Arousal can be mental, emotional, or physical. The reticular activating system (RAS) regulates arousal and is within the brain stem. Arousal theory states that many factors influence arousal, including food, neurotransmitter levels, emotions, and the physical environment. Optimal levels of arousal aid human behaviour, but less than optimal levels (too much or too little) hinder us. Yerkes-Dodson law encapsulates this by stating that an optimal level of stress corresponds to an optimal level of performance.

Attention can be defined as a state of consciousness in which a person can attend to a stimulus and varies in its timespan or breadth. Attention is a vital part of memory, cognitive health and learning knowledge. Some key terms when describing attention are:

• Selective attention – Being able to attend to a specific stimulus despite distractions.
• Divided attention – Attending to different stimuli at the same time. 
• Executive attention – Being able to regulate oneself to focus on the task.
• Sustained attention (Attention span) – Being able to attend to an individual stimulus over a prolonged period. 

Sleep

Sleep is vitally important to physical and mental health. Although some aspects of how and why we sleep are still poorly understood, there is an understanding that sleep occurs in a cyclical phase, and there are two main types of sleep. REM (Rapid eye movement) sleep and NREM (Non-rapid eye movement) sleep. NREM sleep can be further divided into four distinct stages lasting for roughly 90 to 120 minutes, each with different EEG patterns described below.

REM sleep is characterised by skeletal muscle paralysis, increased neural activity and blood flow, rapid eye movements with closed eyelids, and dreaming. REM sleep typically starts 90 minutes after you fall asleep, with each REM cycle getting longer and longer, initially lasting 10 minutes, with the final REM of a night lasting an hour. The brain is highly active throughout REM sleep, with increased demands for glucose and blood flow.

ECG recording in NREM sleep stages

Hypnagogic stage or W stage – Initially, beta waves are seen, but as individuals become more drowsy, alpha waves start to predominate.

Stage 1 – Light sleep – Starts with a reduction of alpha waves being replaced by theta waves.

Stage 2 – Moderately deep sleep – Sleep spindles seen on EEG. Sleep spindles play an essential role in memory consolidation.

Stage 3 – Deep sleep – Delta waves replace sleep spindles: blood pressure, heart rate, and body temperature drop. Profoundly deep sleep in which the body repairs and strengthens the immune system, also the stage when sleepwalking happens.

Dreams

The phenomenon of dreaming and understanding the purpose of dreams is an area of ongoing psychological and neuroscientific enquiry. Sigmund Freud made a name for himself by proposing ideas around dreams being caused by unconscious thoughts or repressed desires and that they are a valuable way of connecting the conscious and unconscious mind. Freud called the apparent content of dreams ‘manifest content’ and the repressed desires ‘latent content’. Many modern psychotherapeutic theories build on early psychoanalyst’s work by endorsing the notion that dreams carry meaningful content linked to emotional processing and touch on unresolved conflicts of waking life.

Francis Crick argued that dreams constitute ‘reverse learning’ or a period of debugging of neural networks wherein extraneous information was evaluated and then consolidated or forgotten.

Jonathan Winson argued that biological and psychological explanations for dreaming could be combined by considering dreams as part of the memory or information processing that constitutes the unconscious mind. He also stated that dreams could be regarded as a type of ‘overnight therapy’ whereby upsetting memories or emotions were processed, and resultantly, the brain could be in better neurochemical balance by diminishing neurotransmitters associated with the stress of unresolved psychological conflicts.

Parasomnias and other sleep-wake disorders

Parasomnias are a group of sleep disorders characterised by abnormal motor or behavioural events that occur during sleep transitions. Parasomnias can occur during NREM or REM sleep and are more common in children than adults. Parasomnias are associated with neurological or neurodevelopmental disorders but can also be idiopathic or associated with psychiatric illness. In children, NREM parasomnias occur more frequently than REM parasomnias. 

Sleepwalking is an example of parasomnia that causes ambulatory behaviour during stage three sleep. Most childhood parasomnias are benign and remit with age. However, adult parasomnias tend to be more challenging to manage.

Some key parasomnias with regards to the Paper A exam are:

• Somnambulance – Also known as sleepwalking, this can occur during stage 3 sleep. The affected person may mobilise independently whilst remaining in NREM sleep. Whilst not inherently dangerous, a risk can be presented from accidental injury.
• Night terrors – Abrupt terror and partial arousal from NREM sleep. High levels of autonomic arousal, e.g., racing heart, excessive sweating, gasping shallow breaths. Often difficult to reassure in the moment and may not remember the event in the morning.

Other sleep-wake disorders

• Nightmare disorder – Recurrent unpleasant dreams that result in abrupt waking from REM sleep with associated anxiety. However, the affected person is rapidly orientated to and reassured by their surroundings and will often remember the event in the morning.
• Insomnia – Perceived difficulty in initiating or maintaining sleep despite adequate opportunity. It can be short-term (Several times a week for less than three months) or chronic (Several times a week for more than three months.)

Narcolepsy – Complex condition increasingly managed by specialist neurology services, but defined for our purposes as daily periods of irrepressible need to sleep. Often associated with abnormal REM sleep architecture on monitoring, as well as a frequent correlation with hypothalamic dysfunction.

Biorhythms and sleep deprivation

The most well-known biological rhythm is the circadian rhythm. The pineal gland regulates the circadian rhythm. Melatonin is secreted by the pineal gland in a biological rhythm, which runs as a feedback loop dependent on how much light stimulation the retinal cells receive (daytime release is low, peak is the middle of the night). Artificial light at night can diminish melatonin secretion, as can supplementation with synthetic melatonin, and this can disrupt the circadian rhythm and produce sleep deprivation and consequent ill health.

Sleep is critical for the proper function of a multitude of bodily systems. Therefore, deficiencies in sleep quality or adequate duration of sleep are termed sleep deprivation. Sleep deprivation can occur due to extrinsic reasons (shift work), psychiatric illness (PTSD nightmares), or physical illness (sleep apnoea).

Sleep deprivation is known to increase vulnerability to physical and psychological distress and has been evidenced to cause abnormal:

• Hormone secretion.
• Metabolic activity.
• Sympathetic nervous system functioning.
• Memory and cognition problems.

Sleep deprivation has been evidenced to exacerbate illnesses such as hypertension, coronary artery disease, metabolic syndrome, IBD, peptic ulceration, depression, anxiety and T2DM, as well as ongoing research linking sleep deprivation with carcinogenesis. Although the evidence between poor physical health and poor sleep is emerging, the relationship is undoubtedly felt to be bi-directional.

Hypnosis and suggestibility

Freud used hypnotherapy in his clinical practice and, similarly to Milton Erickson, believed hypnotherapy was a means to communicate with the unconscious mind. Later, psychologists like Nicholas Spanos thought patients could receive hypnotic prompts via the conscious mind. Hypnotherapy still has some clinical use in disorders such as anxiety, smoking cessation and trauma. It involves the induction of an altered state of consciousness whereby people detach from solely external attention to look inside themselves. Hypnotic states are felt to increase susceptibility to suggestion, and this suggestibility is what is used to treat illness.

Ernest Hilgard wrote about the ‘domain of suggestion’ in his article ‘The Domain of Hypnosis’ and identified that the propensity of a patient to be hypnotised and respond to hypnotic commands correlated with how likely a person is to respond to placebo treatments, be misled by false information (including memories), and experience illusionary phenomena.

Hypnotic ‘suggestibility’ or ‘susceptibility’ refers to the degree to which a person readily responds to hypnotism. 

The role theory states that hypnotised people are fulfilling a sociopsychological role and respond to external expectations when they demonstrate behavioural responses rather than any true communication with the unconscious mind.

Meditation

Reaching an altered state of consciousness through meditation is an ancient ritual which is amassing a growing body of evidence as a psychotherapeutic technique. Meditation has been shown to affect neural pathways between the prefrontal cortex and amygdala, serving to improve the processing of emotional responses.

Meditation has been shown to increase alpha and theta waveforms on EEG testing and is increasingly demonstrating quantifiable results as a treatment for PTSD. 

Meditation uses introspection to create a sense of control/calm. For example, mindfulness meditation can focus on the sense of self, or in PTSD, the focus can be on accessing and ultimately addressing painful memories. Meditation emphasises being in the present moment and can strengthen a patient’s ability to avoid ruminating about anxieties (a disease of the future) or distressing experiences of grief (a disease of the past.)

References

• Agid, O., Kohn, Y. and Lerer, B., 2000. Environmental stress and psychiatric illness. Biomedicine & pharmacotherapy, 54(3), pp.135-141.
• Richard Gross Hachette 2020. Psychology: The Science of Mind and Behaviour 8th Edition.
• Tryon Warren. 2014. Cognitive Neuroscience and Psychotherapy :Network Principles for a Unified Theory. Elsevier.
• Bandy, C, Dillbeck, M., Sezibera, V., Taljaard, L., de Reuck, J., Wilks, M., Shapiro, D., Peycke, R. 2019. Psychological Reports. Reduction of PTSD in South African University Students Using Transcendental Meditation Practice.
• Kang SS, Erbes CR, Lamberty GJ, Thuras P, Sponheim SR, Polusny MA, Moran AC, Van Voorhis AC, Lim KO. 2018. Transcendental meditation for veterans with post-traumatic stress disorder. Psychol Trauma. Nov;10(6):675-680. 
• Selye H. 1956. The Stress of Life. New York: McGraw-Hill Book Company.
• Luthar SS, Cicchetti D, Becker B. 2000. The construct of resilience: a critical evaluation and guidelines for future work. Child Dev; 71(3):543-62.