Psychopathology: disturbances of emotions, volition, and drives – characteristics and clinical conditions

At a glance

1. Mood is the sustained emotional state, the climate; affect is its moment-to-moment expression, the weather. The mental state examination records mood in the patient's words and as observed, and the range, reactivity and congruence of affect.
2. Depressed mood with anhedonia is the core of depression; elevated, expansive or irritable mood the core of mania. Depressed mood always leads to questions about hopelessness and suicide.
3. Blunted and flat affect are negative symptoms of schizophrenia; incongruous affect points to schizophrenia; labile affect to mania, organic states and personality disorder; emotional incontinence to brain damage (stroke, multiple sclerosis, dementia).
4. Volition can be weakened (hypobulia, abulia, the avolition of schizophrenia), increased (hyperbulia in mania), split (ambitendency) or surrendered (automatic obedience, negativism) in catatonia.
5. The drives (appetite, sleep, sexual drive) change in predictable ways: the somatic syndrome of depression, the reduced need for sleep that heralds mania, the increased appetite and sleep of atypical depression.
6. Impulse-control disorders are acts preceded by mounting tension and followed by relief or pleasure; compulsions are resisted and give no pleasure.
7. Aggression is linked most strongly with intoxication, past violence, antisocial personality and some psychotic symptoms, but most people with mental illness are never violent, and they are more often victims than perpetrators.

01Disturbances of emotion

Mood and affect

Emotion is a feeling with its bodily changes and its expression. Mood is the prevailing emotional state over days or weeks; affect is the emotion shown at a given moment and in response to events. In the mental state examination the patient's own description is the subjective mood and the doctor's observation the objective mood, and the two can differ, as in the smiling patient who is severely depressed. Affect is described by its range, its reactivity (does it brighten when the conversation does?), its intensity and its congruence with what is said.

Disturbances of mood

In mania the mood can be irritable rather than elated, and in mixed states depressive and manic features come together, with a high risk of suicide. In depression the "biological" symptoms follow the mood (see Drives below), and mood-congruent delusions of guilt, poverty or illness appear in its psychotic form.

Disturbances of affect

02Disturbances of volition

Volition, the will, is the capacity to choose a goal and carry it through: a motive, the weighing of competing motives, a decision and its execution, sustained against obstacles. It depends on the frontal lobes, the anterior cingulate and the basal ganglia, and on dopamine signalling of reward.

The five negative symptoms of schizophrenia, by a widely used consensus, are blunted affect, alogia, anhedonia, asociality and avolition; they predict poor function more than the positive symptoms do and respond poorly to drugs. Before calling them primary, the doctor looks for their mimics: depression, the sedation and parkinsonism of antipsychotics, and an understimulating environment.

03Disturbances of drives

The drives are the basic biological urges: hunger and thirst, sleep, sex, self-preservation, care of the young, and aggression. They are organised by the hypothalamus and the limbic system (simplified: hunger and satiety in hypothalamic nuclei with leptin and ghrelin, the sleep-wake rhythm in the suprachiasmatic nucleus and the orexin neurons, reward in the dopamine pathways), and they are among the first things a mental illness changes.

Appetite and eating

Psychogenic polydipsia can cause water intoxication: dilutional hyponatraemia with confusion, seizures and coma, worsened by the inappropriate antidiuretic hormone secretion that antipsychotics, smoking and the illness itself can cause, and by a diet low in salt and protein, which limits how much water the kidneys can clear.

Sleep

Sexual drive

Loss of libido is seldom mentioned unless asked about, and asking matters because drug-induced sexual dysfunction is a common, hidden reason for stopping treatment. Disorders of sexual preference (F65) concern the direction of sexual interest rather than its strength.

Impulses

In the habit and impulse disorders of ICD-10 (F63) the person fails to resist an urge to an act that harms them or others, with mounting tension before it and pleasure, gratification or relief during it; afterwards there may be regret. This sets them apart from compulsions, which give no pleasure and are resisted.

Dopamine agonists given for Parkinson's disease or restless legs can cause new pathological gambling, shopping, eating and hypersexuality, which improve when the dose is reduced (see antiparkinsonian drugs).

Aggression

Aggression ranges from irritability and hostility through threats to violence against people or property. It is more likely with:

• alcohol and stimulant intoxication, the strongest and commonest link;
• past violence, the best single predictor, and antisocial or emotionally unstable personality disorder;
• psychosis with persecutory delusions, command hallucinations or a sense of being controlled, especially when the patient feels threatened, and mania;
• delirium, dementia, intellectual disability and frontal lobe lesions;
• akathisia, frustration, and settings that feel coercive or crowded.

Management starts with de-escalation and a safe environment, and medication is used only when that fails (see aggressive behaviour).

Self-preservation and care

The drive to stay alive is lost in suicidal states, and the drive to care for oneself in self-neglect, from depressive and psychotic neglect to the squalor of severe self-neglect in old age (Diogenes syndrome). The drive to care for a newborn can be disturbed in severe postnatal depression and puerperal psychosis, in which thoughts of harming the baby that come from delusions are an emergency, unlike the unwanted, resisted intrusive thoughts of harm that many anxious new mothers have.

Check yourselfAnswer, then say how sure you were: a lucky guess still counts as a weak point.

1A 23-year-old man with a two-year history of withdrawal and odd beliefs smiles and laughs while telling you that his mother died last month, and says he is sad about it. What is this called?

Labile affectIncongruous affectEmotional incontinenceEuphoria

2A 72-year-old woman who has had several strokes bursts into tears many times a day at trivial things, such as a nurse saying good morning. Each episode stops as suddenly as it starts, and she says she does not feel sad. What is the most likely explanation?

Emotional incontinence, pathological crying from damage to the pathways that control emotional expressionA severe depressive episodeThe labile mood of a mixed affective stateAlexithymia

3A 55-year-old man has been depressed for six weeks. He wakes at 4 am instead of 7, feels worst in the morning, has lost 6 kg in the past month, takes no pleasure in anything and has lost interest in sex. Which ICD-10 specifier describes this pattern?

With psychotic symptomsWith atypical featuresWith seasonal patternWith somatic syndrome

4A 60-year-old man, after surgery for a ruptured anterior communicating artery aneurysm, sits in a chair all day unless prompted. He answers questions briefly and correctly when spoken to, does not seem sad, and starts nothing on his own. What is the best description?

Depressive psychomotor retardationCatatonic stuporAbulia, from damage to the medial frontal lobesNegativism

5A 45-year-old man with chronic schizophrenia drinks more than 10 litres of water a day. He is brought in confused after a seizure, and his plasma sodium is 118 mmol/L. What is the most likely cause?

Diabetes mellitusPsychogenic polydipsia, with water intoxicationNephrogenic diabetes insipidus from lithiumA primary brain tumour