Mental State Examination – Part 2

Introduction

In most branches of medicine, history taking is followed by physical examination, with each sub-specialty having its own unique method. In psychiatry, the mental state examination begins as soon as you see the patient and continues while you are painstakingly going through all the sub-headings of history taking. Sometimes only a few minutes are needed to complete the MSE formally, after most of the available time has been spent on history taking.

The Mental State Examination is, at its core, the keen observation of the patient's appearance, behaviour, and mood — followed by questions about their beliefs, any perceptual abnormalities, and then cognition, insight, and interpretation of findings.

An important distinction from physical examination is that in psychiatry, we also record what the patient thinks, feels, and believes about their own appearance, behaviour, and thought processes — and what they believe the underlying cause of their condition to be, and what treatment might help. In medicine, a patient may have no opinion about their pallor or raised JVP; in psychiatry, almost all patients have some personal interpretation of their signs and symptoms, and this often provides important diagnostic clues.

The key diagnostic challenge is the disparity or incongruity between the patient's complaints and their observed behaviour. A patient with dementia will often confidently deny any memory problems — yet moments later cannot recall the day of the week. A patient with anorexia nervosa will deny any concern about their weight — despite being markedly emaciated. These incongruities are themselves significant clinical findings.

When presenting a mental state, describe findings in plain, precise English. Avoid vague or pejorative terms such as "hysterical" or "bizarre." Quote the patient's own words verbatim where a key sign or symptom is being described. Mention both what is present and what is notably absent in support of your primary diagnosis.

Appearance and Behaviour

The patient's appearance and general behaviour may give important diagnostic clues. Observe and describe:

• General appearance: estimated age (do they look older or younger than their stated age?), build, dress, and level of self-care and hygiene
• Eye contact: maintained, intermittent, avoided, or intense
• Psychomotor activity: agitation (inability to sit still, hand-wringing, pacing) or retardation (slowed movement and speech, long delays before answering); catatonic features (rigidity, waxy flexibility, posturing, negativism, echopraxia)
• Rapport: the quality of the interpersonal connection — was it easy to establish rapport, or was the patient guarded, suspicious, dismissive, or hostile?
• Behaviour: any unusual, stereotyped, or disorganised behaviour; evidence of responding to hallucinations (e.g. apparently listening to or talking to unseen others)

From hypomanic excitement to withdrawn depression; from paranoid guardedness to confused, unkempt self-neglect — the clinician's first observations often point strongly towards the diagnosis. The relatives' appearance and behaviour can also be informative: in hypomania, the patient often appears the most energetic in the room while the family appear exhausted; in dementia, the patient's "head-turning sign" — glancing repeatedly towards an anxious spouse for reassurance when answering questions — is a characteristic finding.

During home visits, the state of the home environment provides further valuable information: the tidiness of the living space, the state of the kitchen and refrigerator, whether pets are being adequately cared for, and how the patient greets you at the door.

Speech

In the MSE, the focus is on the form and quality of speech — not its content (which is addressed under Thought). Describe:

• Rate: fast (pressure of speech, as in mania), slow (as in depression, sedation), or normal
• Volume: loud, quiet, or normal
• Tone and prosody: monotonous and flat (as in depression or negative symptoms of schizophrenia) or varied and expressive
• Spontaneity: does the patient volunteer information spontaneously or give only minimal answers when directly questioned?
• Fluency and articulation: any dysarthria (slurred speech, suggesting neurological cause or intoxication), dysphagia, or dysphonia
• Neologisms: new words constructed by the patient, or existing words used with a private meaning (a feature of schizophrenia)
• Poverty of speech: reduced amount of spontaneous speech (seen in depression, negative symptoms)

Speech abnormalities are commonly seen in neurological disorders, depression, mania, schizophrenia, and learning disability.

Affect and Mood

These terms are often confused. It is important to describe both:

• Mood (subjective): the patient's own description of their prevailing emotional state — "I have felt low and hopeless for the last three months." Mood is a sustained emotional tone.
• Affect (objective): the clinician's observation of the patient's immediate emotional responsiveness during the interview. A normal affect is warm and reactive, with appropriate facial expressions. Affect can be: blunted (reduced range and intensity of emotional expression), flat (absence of emotional expression), labile (rapidly shifting between states), or incongruent (not matching the stated mood or thought content — e.g. smiling while describing being suicidal, which may suggest psychosis or severe dissociation).
• Euthymia refers to a normal, stable mood state.

Note: a patient may smile or laugh during the interview while their overall mood is deeply depressed — this is a brief fluctuation in affect, not an indication of mood. Brief fluctuations in affect are normal. It is only when a mood state is pervasive and correlates with significant functional impairment (at home, socially, and at work) that it is considered pathological.

Thought Process

Thought is examined across three dimensions:

Thought Form (How Thoughts Are Connected)

Disorders of thought form describe how thoughts are linked and communicated:

• Flight of ideas: rapid movement from one topic to another, with discernible — but tenuous — connections (typically mania)
• Loosening of associations (derailment): thoughts shift in an unpredictable, non-goal-directed way, with no logical connection between successive ideas (typical of schizophrenia)
• Tangentiality: the patient begins to answer a question but drifts off-topic and never returns to the original point
• Circumstantiality: the patient eventually reaches the goal of a thought, but via an excessive number of irrelevant details
• Thought blocking: sudden interruption in the train of thought, with the patient unable to continue — they may describe the thought as being "removed from their mind" (passivity phenomenon; seen in schizophrenia)
• Over-inclusive thinking: inability to exclude irrelevant material, leading to broadening and blurring of conceptual boundaries
• Poverty of thought (alogia): markedly reduced quantity of thinking and speech, as seen in negative symptoms of schizophrenia or severe depression

Thought Content (What the Patient Is Thinking)

Disorders of thought content describe the abnormal ideas the patient holds:

• Delusions: fixed false beliefs, firmly held with absolute conviction, out of keeping with the patient's cultural and educational background, and not amenable to reasoned argument. Types include: persecutory (most common), grandiose, referential (ideas of reference — the belief that ordinary events have special personal significance, e.g. a TV announcer is speaking directly to the patient), nihilistic (Cotard's delusion — the belief that one's body or world does not exist), somatic, erotomanic, jealous (Othello syndrome), and delusional perception (a normal perception is followed by an abnormal delusional interpretation). First-rank (Schneiderian) delusions — passivity of thought, thought insertion, thought withdrawal, thought broadcasting — are strongly associated with schizophrenia.
• Overvalued ideas: an isolated, strongly held idea — not of delusional intensity — that dominates the patient's life (e.g. in anorexia nervosa or dysmorphophobia)
• Obsessions: recurrent, intrusive, unwanted thoughts, images, or impulses that the patient recognises as their own but cannot dismiss, and which are experienced as distressing. Typically accompanied by compulsions in OCD.
• Suicidal and homicidal ideation: always actively enquire about these and document the response clearly

Goal-Directedness of Thought

Whether the patient's thinking is goal-directed — able to reach a conclusion in a coherent, logical manner — reflects their capacity for attention, concentration, and executive function.

Perception

Perceptual abnormalities require systematic evaluation across each sensory modality. Key phenomena include:

Hallucinations

A hallucination is a perception in the absence of an external stimulus — experienced as real, arising in external space, and occurring in clear consciousness (not in the hypnagogic/hypnopompic state on falling asleep or waking). Types:

• Auditory hallucinations — the most common type in schizophrenia. May be elementary (bangs, whispers) or complex (voices). Voices may speak to the patient (second person) or about the patient (third person — commenting or discussing). Command hallucinations (voices instructing the patient to act) carry significant risk. Specifically enquire: Is the voice clear and audible? Does it seem to come from outside the head? Does the patient recognise the voice? Is it one voice or several? Do the voices talk directly to the patient or about the patient? Does the patient feel compelled to obey?
• Visual hallucinations — more strongly associated with organic causes (delirium, substance intoxication or withdrawal, dementia, epilepsy) than functional psychosis, though they can occur in schizophrenia
• Olfactory hallucinations — smelling things others cannot; may suggest temporal lobe epilepsy or schizophrenia
• Gustatory hallucinations — abnormal tastes
• Tactile (somatic) hallucinations — sensations of being touched, or of insects crawling under the skin (formication — classically associated with cocaine and alcohol withdrawal)

Pseudohallucinations

Pseudohallucinations are experienced within internal or subjective space (e.g. "inside my head"), and the patient retains insight that they are not real perceptions. They are less diagnostically specific than true hallucinations.

Illusions

An illusion is a misinterpretation of a real external stimulus (e.g. seeing a shadow and believing it to be a person). Illusions may occur normally under conditions of fatigue, fear, or reduced sensory input, but persistent illusions may indicate delirium or intoxication.

Depersonalisation and Derealisation

Depersonalisation is the distressing experience of feeling detached from one's own thoughts, feelings, or body — as if an observer of oneself. Derealisation is the experience that the external world feels unreal, dreamlike, or remote. Both can occur as isolated phenomena (e.g. with fatigue, anxiety, cannabis use) or as features of depressive disorder, dissociative disorder, or complex PTSD.

Cognition

By the time you reach this point in the assessment, you will usually have formed a working impression of the patient's cognitive state from their performance throughout the interview. If the patient has had difficulty giving simple personal details or following the thread of the conversation, shift to a more detailed cognitive assessment early in the process rather than leaving it until the end.

The Mini Mental State Examination (MMSE, Folstein 1975) is the most widely used brief screening tool and covers orientation, registration, attention and calculation, recall, and language. Maximum score is 30; scores below 24 suggest cognitive impairment. The Montreal Cognitive Assessment (MoCA) is more sensitive for mild cognitive impairment and includes executive function and visuospatial tasks.

Document orientation (time, place, person), attention (serial 7s, months of the year backwards), concentration, short-term and long-term memory, and — if indicated — language, praxis, and executive function. If cognitive impairment is detected, a full specialist dementia assessment should be arranged.

Insight and Judgement

Evaluation of the patient's insight is an important and often underappreciated aspect of the psychiatric examination. Insight is not a binary — present or absent — but a spectrum. It has several dimensions: does the patient recognise they are unwell? Do they attribute their experiences to a mental illness? Do they accept the need for treatment? Do they understand the effects of their illness on others?

Insight is significant for prognosis (those with better insight generally have better outcomes), for medication adherence, and for medicolegal decisions about capacity and the need for compulsory treatment.

Questions to elicit insight and judgement include:

• What do you think is the problem here?
• Do you feel that you may have some emotional or mental health issues that require help?
• What do you think may be the underlying cause of your problem?
• What investigations do you think might be helpful?
• What are your views on the best treatment options?
• Who else do you think should be involved in managing your care?

The patient's responses to these questions will also help you decide whether they can be treated as an outpatient or may require hospital treatment, and whether they can be treated informally or whether compulsory treatment under the Mental Health Act may need to be considered.