People with schizophrenia often find it hard to do many of the day-to-day things that everyone else takes for granted. Simple tasks like eating healthily and washing can be challenging and more complex needs like developing relationships with other people and finding and holding down a job can seem like mountains to climb.
Researchers refer to these difficulties as ‘functional impairments’ and often investigate the likely causes of these problems. It seems logical that there is a link between the ability to recognise emotions and this kind of social functioning, but it’s always nice when a systematic review comes along to confirm or refute what we instinctively think.
Researchers from the University of Pennsylvania School of Medicine have conducted a meta-analysis of observational studies that investigate correlations between emotional perception and function in schizophrenia. They searched PubMed and PsychInfo up to September 2010 and found 25 cross-sectional studies (including 1,306 patients, mean age 36.7 years, 64% men, 63% Caucasian) that met their inclusion criteria.
Emotional perception was assessed in two main ways:
- Tasks that involved identifying emotions like happiness/sadness and attaching them to facial expressions or voices
- Tasks that assessed the ability to identify differences between intensities of emotional expressions
Social functioning was assessed in four main ways:
- Social behaviour assessed by staff
- Social skills measured through role-play looking at specific skills such as eye contact
- The ability to solve everyday social problems
- The ability to function independently in the community, i.e. socially and at work
The researchers found no evidence of publication bias in the trials they included, but they did find significant heterogeneity (p<0.001, I2=54.55) and so used both random effects and fixed effects models in their analysis. A meta-regression analysis was also carried out to find out if other variables were having a major influence, e.g. gender, age, ethnicity, education, age of onset, duration of illness, symptoms and current treatment.
Here’s what they found:
- There was a significant relationship between emotional perception and social functioning (effect size 0.31, 95% CI 0.13 to 0.49, p=0.001)
- The ability to identify emotions was positively associated with social functioning (24 studies; effect size 0.36, 95% CI 0.14 to 0.57; I2=60.63, p for heterogeneity <0.001)
- The strength of this association was significantly affected by gender, race and positive/negative symptoms
The authors concluded:
Emotion identification deficits are associated with functional impairments in schizophrenia and moderated by sex, race and symptoms. This has implications for treatment efforts to improve outcomes.
Irani F, Seligman S, Kamath V, et al. A meta-analysis of emotion perception and functional outcomes in schizophrenia. Schizophr Res 2012; 137: 203– 11. [PubMed abstract]