HÖzel et Al. (2011)

• Neuroplasticity – This is a foundational concept in the study. Neuroplasticity refers to the brain’s ability to reorganize itself by forming new neural connections throughout life
• Stress Reduction and Psychological Well-being – The study explores how mindfulness-based interventions, like MBSR, can reduce stress and improve overall psychological health. This is based on the theory that mindfulness can alter one’s relationship to stressful events, thereby reducing the psychological impact of stress.
•  The focus on specific brain areas (like the hippocampus, PCC, TPJ, and cerebellum) is based on their known roles in functions such as memory, learning, emotional regulation, and self-referential processing. 
• Aims

  • Investigate whether participation in an 8-week Mindfulness-Based Stress Reduction course (MBSR) could lead to changes in gray matter concentration in the brain.
  • Identify brain regions that changed in association with participation in the MBSR course.ç
• Procedure

  The researchers used a method called voxel-based morphometry to measure changes in gray matter concentration in the brains of participants who completed an eight-week mindfulness-based stress reduction (MBSR) program. 
• Study participants

  • 18 healthy, right-handed individuals
  • Enrolled in the MBSR program
  • Recruited from four MBSR courses held at the Center for Mindfulness at the University of Massachusetts Medical School
  • Physician- and self-referred individuals from across New England who were seeking stress reduction
• Participants were included in the study if they self-reported as physically and psychologically healthy and not taking any medications
• Inclusion criteria

  • No meditation classes in the past 6 months
  • No more than four classes in the past 5 years, or 10 classes in their lifetime
  • 25 to 55 years old
  • No contraindications for MRI scanning (i.e., metallic implants, claustrophobia)
  • Commitment to attend all eight classes and perform the prescribed daily homework
• Pre-post design


  Researchers measured gray matter concentration in participants' brains before and after they completed the MBSR program
• Control group

  • 17 individuals who did not complete the MBSR program
• Controls used by researchers

  1. Ensured participants had no metallic implants or claustrophobia

  2. Ensured participants had no other meditation experience in past 6 months, no more than 4 classes in past 5 years, or 10 classes in lifetime
• Data collection

  • MRI scans to measure gray matter concentration in participants' brains
  • Demographic information including age, gender, ethnicity, and education level
• Results

  1. Increase in Gray Matter Concentration in the Left Hippocampus: The MBSR group showed a significant increase in gray matter concentration in the left hippocampus compared to the control group.
• Results

  1. Whole Brain Analysis: Exploratory whole brain analysis revealed four clusters with significantly greater gray matter concentration at the post time-point compared to the pre time-point in the MBSR group. These regions include:

  • Posterior Cingulate Cortex (PCC)
  • Left Temporo-Parietal Junction (TPJ)
  • Two clusters in the cerebellum (one in the cerebellar vermis and brainstem, and the other in the lateral parts of the posterior and flocculonodular lobe)
• results

  1. Control Group Analysis: No significant changes in gray matter concentration were observed in the control group for these regions, except for a decrease in the PCC cluster.
• 1. MBSR Group

  • There were significant increases in gray matter concentration in all measured brain regions, including the left hippocampus, posterior cingulate cortex (PCC), left temporo-parietal junction (TPJ), cerebellar vermis/brainstem, and lateral cerebellum.
• 1. Control Group

  • No significant changes were observed in most regions, except for a decrease in gray matter concentration in the PCC.
• Use of a control group


  • Allowed researchers to compare changes in gray matter concentration between the MBSR group and the control group
  • Strengthened the internal validity of the study by ruling out alternative explanations for the observed changes in gray matter concentration
• Use of voxel-based morphometry (VBM)


  • Well-established method for measuring changes in gray matter concentration
  • Strengthened the validity of the study's findings by providing a reliable and objective measure of changes in gray matter concentration
• Use of a standardized mindfulness program (MBSR)


  • Well-established and widely used mindfulness program
  • Strengthened the external validity of the study by increasing the generalizability of the findings to other populations and settings
  • Allowed for replication of the study's findings by other researchers
• Small sample size

  • Reduces the generalizability of the study's findings
  • Increases the risk of Type II errors (i.e., failing to detect a true effect)
  • A larger sample size would increase the statistical power of the study and improve the generalizability of the findings
• Lack of randomisation

  • Increases the risk of selection bias, which occurs when participants in one group differ systematically from participants in another group
  • A randomized design would have reduced the risk of selection bias and increased the internal validity of the study
• Lack of blinding


  • Increases the risk of experimenter bias, which occurs when the researchers' expectations or beliefs influence the outcome of the study
  • Blinding the researchers to the group assignment of the participants would have reduced the risk of experimenter bias and increased the internal validity of the study