Symptoms and signs: Cognition, perception, emotional state and behaviour

A paracusia, or auditory hallucination, is a form of hallucination that involves perceiving sounds without auditory stimulus.

Alice in Wonderland Syndrome (also known as Todd's syndrome, or lilliputian hallucinations) is a disorienting neurological condition that affects human perception.

Disorders of consciousness are organic mental disorders in which there is impairment of the ability to maintain awareness of self and environment and to respond to environmental stimuli.

A hallucination is a perception in the absence of external stimulus that has qualities of real perception.

An aura is a perceptual disturbance experienced by some with migraines or seizures before either the headache or seizure begins.

Anosognosia (/æˌnɒsɒɡˈnoʊziə/, /æˌnɒsɒɡˈnoʊʒə/; from Ancient Greek ἀ- a-, "without", νόσος nosos, "disease" and γνῶσις gnōsis, "knowledge") is a deficit of self-awareness, a condition in which a person who suffers some disability seems unaware of the existence of his or her disability.

Hysteria, in the colloquial use of the term, means ungovernable emotional excess.

An out-of-body experience (OBE or sometimes OOBE) is an experience that typically involves a feeling of floating outside one's body and, in some cases, the feeling of perceiving one's physical body as if from a place outside one's body (autoscopy).

Visual release hallucinations, also known as Charles Bonnet syndrome (CBS), is the experience of complex visual hallucinations in a person with partial or severe blindness.

Anhedonia (/ˌænhiˈdoʊniə/ AN-hee-DOH-nee-ə; Greek: ἀν- an-, "without" and ἡδονή hēdonē, "pleasure") is the inability to experience pleasure from activities usually found enjoyable, e.

Alcohol withdrawal syndrome is a set of symptoms that can occur when an individual reduces or stops alcohol consumption after long periods of use.

Splitting (also called black-and-white thinking or all-or-nothing thinking) is the failure in a person's thinking to bring together the dichotomy of both positive and negative qualities of the self and others into a cohesive, realistic whole.

Passive-aggressive behavior is the indirect expression of hostility, such as through procrastination, stubbornness, sullen behavior, or deliberate or repeated failure to accomplish requested tasks for which one is (often explicitly) responsible.

Delusional parasitosis, also known as delusional infestation or Ekbom's syndrome, is a delusional disorder in which individuals incorrectly believe they are infested with parasites, insects, or bugs, whereas in reality no such infestation is present.

Dissociative fugue, formerly fugue state or psychogenic fugue, is a DSM-5 dissociative disorder.

A minimally conscious state (MCS) is a disorder of consciousness distinct from persistent vegetative state and locked-in syndrome.

Unconsciousness is a state which occurs when the ability to maintain an awareness of self and environment is lost.

Allodynia (Ancient Greek άλλος állos "other" and οδύνη odúnē "pain") refers to central pain sensitization (increased response of neurons) following painful, often repetitive, stimulation.

A stereotypy (/ˈstɛriəˌtaɪpi, ˈstɪər-, -ioʊ-/, STAIR-ee-oh-TEYE-pee or STEER-ee-oh-TEYE-pee) is a repetitive or ritualistic movement, posture, or utterance.

Autophony or tympanophony is the unusually loud hearing of a person's own voice.

Formication is the medical term for a sensation that exactly resembles that of small insects crawling on (or under) the skin.

Emotional detachment, in psychology, can mean two different things.

A fixed fantasy — also known as a "dysfunctional schema" — is a belief or system of beliefs held by a single individual to be genuine, but that cannot be verified in reality.

Syncope, also known as fainting, is defined as a short loss of consciousness and muscle strength, characterized by a fast onset, short duration, and spontaneous recovery.

An intrusive thought is an unwelcome involuntary thought, image, or unpleasant idea that may become an obsession, is upsetting or distressing, and can feel difficult to manage or eliminate.

Suicidal ideation, also known as suicidal thoughts, concerns thoughts about or an unusual preoccupation with suicide.

Presyncope is a state consisting of lightheadedness, muscular weakness, blurred vision, and feeling faint (as opposed to a syncope, which is actually fainting).

Obtundation refers to less than full alertness (altered level of consciousness), typically as a result of a medical condition or trauma.

Clouding of consciousness, also known as brain fog or mental fog, is a term used in medicine denoting an abnormality in the regulation of the overall level of consciousness that is mild and less severe than a delirium.

Somnolence (alternatively "sleepiness" or "drowsiness") is a state of strong desire for sleep, or sleeping for unusually long periods (compare hypersomnia).

A vagal episode or vasovagal response or vasovagal attack (also called neurocardiogenic syncope) is a malaise mediated by the vagus nerve.

Anosodiaphoria is a condition in which a person who suffers disability due to brain injury seems indifferent to the existence of their handicap.

Vegetative symptoms are disturbances of a person's functions necessary to maintain life (vegetative functions).

Waxy flexibility is a psychomotor symptom of catatonic schizophrenia which leads to a decreased response to stimuli and a tendency to remain in an immobile posture.