Making sense of exercise in schizophrenia - No sweat!

Improving cognitive performance in psychotic disorders through physical exercise (PE) is an exciting area of cognitive rehabilitation research.¹ This is because cognitive performance is a strong predictor of social functioning in those with psychotic disorders, making it an important intervention target.¹

High ‘dose’ exercise improves cognition

A meta-analysis of PE in schizophrenia supports exercise improving cognitive functioning, particularly when administered at higher ‘doses’.² Small to medium effects in global cognition (g=0.33) and working memory (g=0.39) and medium effects for social cognition (g=0.71) and attention (g=0.66) were noted in the study.

Exercise improves cognitive functioning, particularly when administered at higher ‘doses’

Clinicians are well aware that cardiorespiratory fitness and cognition in schizophrenia are related, but what underlies this phenomenon? Is something else going on other than patients merely becoming fitter?

Cardiorespiratory fitness-cognition relationship is derived early, regardless of fitness level

A recent study suggests that this cardiorespiratory fitness-cognition relationship is derived early in the lives of people experiencing psychosis regardless of level of fitness.³ While sought, no correlations between brain-derived neurotrophic factor (BDNF), proBDNF or current levels of physical activity with cognition were apparent in this study.

Cardiorespiratory fitness-cognition relationship is derived early in the lives of people experiencing psychosis

Aerobic improvement – from the sofa?

It appears exercise per se may not even be needed to elicit a beneficial effect. Fascinatingly, active-play video games appeared to enhance aerobic fitness in those with schizophrenia as demonstrated in a small study of 16 patients.⁴ Such ‘treatment regimens’ were both acceptable and enjoyable to patients, with high adherence levels, suggesting the potential feasibility of improving or supplementing aerobic fitness from patients’ sofas.

But what exactly is going on here?

It’s not rocket science – it’s fMRI!

In a proof of concept study, researchers used functional MRI (fMRI) to provide real-time analysis of brain activity based on changes in brain blood flow.⁵ The fMRI was linked to a computer game that involved landing a rocket.

Study participants who experienced auditory hallucinations (AH) had to devise a way to land the rocket – they were given no instruction. Not all patients succeeded but in those who did, reduced activity in the temporal gyrus (TG) – an area associated with speech - was noted. Psychotic Rating Scale (PsyRats), assessment scale, ratings also improved and a reduction in AH was reported.

A single 21-minute session of real-time-fMRI neurofeedback was sufficient to elicit an effect in one study

Subsequently, others have also reported that real-time fMRI neurofeedback (rt fMRI NFB) techniques (a functional task and meditation) have both successfully reduced the frequency of AH.^6,7 In one study, a single 21-minute session of rt-fMRI NFB was sufficient to elicit an effect.⁶

Brain-training can reduce the frequency of positive symptoms

Thus, it appears that training – not only physical but also mental training – can help ameliorate some of the positive symptoms of schizophrenia.