Source (slide): 1. APA 2013, Pages 99–102; 2. APA 2000, Page 299; 3. Wilk et al. Neuropsychology 2005; 19 (6): 778–786, Page 778; 4. NICE clinical guideline 178, Page 4.
Source (notes): APA 2013, Pages 99–102; APA 2000, Page 299–302; Wilk et al. Neuropsychology 2005; 19 (6): 778–786, Page 778; NICE clinical guideline 178, Page 4; Tandon et al. Schizophr Res 2009; 110: 1–23, Table 1; Jones & Buckley. Schizophrenia 2006, Page 7.
Patients with schizophrenia experience a broad range of symptoms including positive, negative, and cognitive symptoms.[APA, 2013; APA, 2000] Mood symptoms, such as, depression, anxiety, anger, hostility, and aggression, may also be present.[APA, 2013].
Positive symptoms appear to reflect an excess or distortion of normal functions, and include distortions in:[APA, 2013; APA, 2000].
- thought content (delusions)
- perception (hallucinations)
- language and thought process (disorganised thought/speech)
- self-monitoring of behaviour (grossly disorganised or catatonic behaviour).
Negative symptoms reflect a decline in, or loss of, normal functions, and include:[APA, 2013; APA, 2000].
- diminished emotional expression and a decrease in motivated self-initiated, purposeful activities (avolition)
- alogia (diminished speech output)
- anhedonia (decreased ability to experience pleasure from positive stimuli)
- asociality (apparent lack of interest in social interactions).
Cognitive symptoms are considered to be a key component of schizophrenia,[Wilk et al. Neuropsychology 2005] and include impairments in:[APA, 2013].
- episodic memory
- executive functions (including language function)
- working memory
- processing speed
- inhibitory capacity.
Clinical manifestations of patients with schizophrenia are very variable.[NICE, 2014] Individuals with schizophrenia experience their own distinct combination of symptoms with a degree of severity that varies between patients and throughout the course of the illness, such that no two cases of schizophrenia are ever exactly the same.[Tandon et al. Schizophr Res 2009; Jones & Buckley. Schizophrenia 2006]