Reduced speech, or alogia, involves speaking less spontaneously or providing unusually brief answers. It concerns the amount and elaboration of communication, rather than necessarily involving incoherent speech. A person may understand a conversation but contribute…Continue Reading
Incoherent speech is communication whose meaning becomes very difficult to understand because words, phrases or sentences do not connect in an intelligible way. Severe examples are sometimes called word salad, although that expression can sound…Continue Reading
Thought blocking is a sudden interruption in the flow of thought or speech. A person may stop mid-sentence and report that the idea has disappeared, even though they intended to continue. The pause can be…Continue Reading
Scientists investigate hallucinations as changes in the processes that construct perception. The brain combines sensory input with expectations, memories and attention. One hypothesis proposes that expectations receive too much weight when external information is uncertain.…Continue Reading
The impact of hallucinations depends on their content, frequency, meaning and the person’s sense of control. A quiet but threatening voice may be more distressing than a loud neutral one. Fear, exhaustion and isolation can…Continue Reading
Persecutory delusions involve the conviction that someone intends to harm, monitor, deceive or unfairly target the person. The perceived threat may involve strangers, neighbours, organisations or people close to them. Ordinary events, such as a…Continue Reading
Grandiose delusions involve beliefs about exceptional identity, importance, power, ability or relationships. A person may believe they possess extraordinary knowledge, have a special mission or maintain a close connection with a famous individual. The belief…Continue Reading
Auditory hallucinations involve hearing sounds without an external source. Voices are a common form in schizophrenia, although people may also hear music, footsteps or other noises. A voice may seem to come from outside the…Continue Reading
Visual hallucinations involve seeing something without a matching external stimulus. They can be simple, such as flashes or shapes, or complex, such as people, animals or complete scenes. They differ from illusions, in which a…Continue Reading
Hallucinations can involve touch, smell, taste or bodily sensations as well as hearing and vision. Tactile hallucinations may feel like crawling, touching or pressure on the skin. Olfactory hallucinations involve smells without an external source…Continue Reading