Key Studies: The effects of mindfulness and meditation on the brain (Desbordes et al. 2012, and Lazar et al. 2005)

Travis DixonBiological Psychology, Criminology, Post-Traumatic Stress Disorder

Mindfulness is growing in popularity and it's an interesting field of study. There are multiple ways this can be incorporated in the course.

These two studies can be used to discuss:

  • The use of technological techniques
  • Neuroplasticity
  • Experimental methods (quasi and true experiments) to study:
    • The brain
    • cognitive processes

Lazar et al. (2005)

 

There have been numerous studies that have compared the brains of Tibetan monks who have thousands of hours of practice in meditation with normal controls. These studies regularly show that the monks’ brains are significantly different to people who have no (or less) meditation experience. But one critique of these studies is that there are numerous extraneous variables that are difficult to control for, since the two groups have numerous other differences besides just meditation experience that could be affecting the results.

So in their study, Lazar et al. (2005) used a matched pairs design to compare the brains of 20 meditation expert practitioners with a control group that had no yoga or meditation practice. The experts were not monks, but were “…typical Western meditation practitioners who incorporate their practice into a daily routine involving career, family, friends and outside interests.” The participants were matched for sex, age, education and race.

Using an MRI, the researchers compared the brain structures of the two groups and the results showed that there were significant differences in cortical thickness between the meditators and the controls in particular areas of the brain, including the prefrontal cortex. The differences between the groups was largest with the older participants.

This study has numerous applications, including showing:

  • That meditation can change the brain (neuroplasticity)
  • How and why technology is used to study the brain (technological techniques)
  • How and why quasi-experimentation is used to study the brain (research methods on the brain and behaviour, as well as research methods on cognitive processes)

Link for original study.

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Both of these studies are useful for explaining how and why technology is used to study the brain and behaviour.

Desbordes et al. (2012)

Previous studies on mindfulness had shown that this practice can have an effect of reducing the activation of the amygdala during the perception of emotional stimuli. This is measured using the common experimental paradigm of having participants in an fMRI viewing images of different types of emotional stimuli (e.g. emotional faces or other types of images) and their brain activity is measured. The earlier research has shown that when people are exposed to angry or other emotional stimuli, mindfulness can reduce their amygdala activation. Desbordes et al. wanted to see if this same effect could happen after mindfulness training even when people were in a resting state in the fMRI.

In this study, fMRIs were used to measure the effects of cognitive practices across three groups who had received different types of cognitive training:

  • Mindfulness Attention Training (MAT)
  • Cognitively-Based Compassion Training (CBCT)
  • No training, but participating in a health discussion group (CTRL)

The researchers used fMRI to measure the function of their brain while they were perceiving emotional stimuli on a screen (positive, negative or neutral stimuli). The results showed that the mindfulness training group had reduced activity in their amygdala when perceiving the negative emotional stimuli.

This study has numerous applications, including showing:

  • How mindfulness might be an effective psychological treatment for people with PTSD (treatments of PTSD)
  • That meditation can change the brain (neuroplasticity)
  • How and why technology is used to study the brain (technological techniques)
  • How and why quasi-experimentation is used to study the brain (research methods on the brain and behaviour, as well as research methods on cognitive processes

Link for original study.

References

Desbordes, G, Lobsang T. Negi, Thaddeus W. W. et al. “Effects of Mindful-attention and Compassion Meditation Training on Amygdala Response to Emotional Stimuli in an Ordinary, Non-meditative State.” Frontiers in Human Neuroscience 6 (2012).

Lazar, Sara W., Catherine E. Kerr, Rachel H. Wasserman, et al. “Meditation Experience Is Associated with Increased Cortical Thickness.” NeuroReport 16.17 (2005): 1893-897.