American Mindfulness Research Association EEG Archives - American Mindfulness Research Association

Two weeks of mindfulness training changes brain waves of depression

Posted 11.28.2017 | by AMRA

Are there biological markers for depression that continue to exist even when the depressive symptoms go away? One possible candidate for such a marker is an electroencephalographic (EEG) waveform called error related negativity (ERN).

ERN is a sharp negative wave that occurs whenever people make a mistake while performing a task. The waveform begins at the start of the error and peaks shortly thereafter. ERNs occur even when people are not consciously aware of having made a mistake.

In healthy individuals, larger ERNs are associated with better executive and attentional control and enhanced self-regulation. People with depression, however, typically have smaller ERNs. When their depressive symptoms improve with treatment, their ERNs continue to be smaller than those of healthy individuals. This raises the possibility that smaller ERNs reflect an underlying biological vulnerability to depression.

Fissler et al. [Cognitive and Affective Behavioral Neuroscience] sought to discover whether brief mindfulness training could help improve ERNs in people with chronic depression.

The researchers recruited a sample of 68 patients (average age = 39 years; 61% female) with histories of chronic or recurring major depression who were currently depressed. They also recruited a comparison sample of 25 healthy controls.

Participants had their EEGs recorded while performing a sustained attention task. A series of digits were displayed individually on a computer screen and participants were told to push the keyboard space bar whenever they saw the digits “0” through “2” and “4” through “9,” but to withhold responding whenever they saw a “3.” The researchers then recorded the total number of errors made to the number “3” and the average ERN magnitude when those errors were made.

Following the initial assessment, members of […]

November 28th, 2017|News|

Emotional reactivity lessens with mindfulness, brain study shows

Posted 06.17.2016 | by AMRA

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One advantage of being mindful is that it allows one to respond to situations with equanimity rather than reacting emotionally in a “knee-jerk” fashion. How does mindfulness help us to do this? According to one theory, mindfulness helps to extinguish our negative emotional reactions. It does this by increasing our exposure to the stimuli that provoke these reactions while helping us to maintain an open, nonjudgmental stance.

Uusberg et al. [Biological Psychology] tested this theory using an electroencephalogram (EEG) to measure the effects of repeatedly viewing negative and neutral images under both mindful and control conditions. They hypothesized that repeated viewing of emotionally-charged images while maintaining mindful awareness would cause a greater reduction in emotional reactions to the images than viewing them without mindfulness.

The researchers recruited 37 meditation-naive volunteers (84% female, average age=27). The participants were shown a series of 30 neutral and 30 negative images while an EEG recorded their late positive potentials (LPPs) in response to those images. LPPs are electrical brain waves that occur 260-1500 milliseconds after viewing a stimulus. They reflect ongoing emotional processing, with larger LPPs reflecting greater degrees of emotional processing. The mean difference in LPP amplitude between negative and neutral images served as a measure of emotional reactivity.

The negative stimuli featured images such as car accidents and brutal attacks, while the neutral stimuli were images of everyday scenes and objects such as hairdryers. Participants viewed subsets of these neutral and negative images under three different conditions: an “attentiveness” condition in which they focused on the visual details of the images; an open-monitoring “mindfulness” condition in which they viewed the images while also attending nonjudgmentally to thoughts, […]

June 17th, 2016|News|

Older adult cognitive decline improves after mindfulness program

Posted 05.19.2016 | by AMRA

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Older adults who complain of subjective cognitive decline (SCD) often appear normal in day-to-day functioning and on clinical assessment, but 60% of them eventually develop either mild cognitive impairment or Alzheimer’s Disease. This makes older adults with SCD a prime target for interventions aimed at preventing or slowing cognitive decline.

Smart et al. [Journal of Alzheimer’s Disease] conducted a randomized controlled pilot study to test the effects of mindfulness training versus a psycho-educational control on measures of attention, brain structure and function, and self-reported cognitive complaints, mood, and mindfulness in adults with SCD.

A sample of 23 healthy older adults and 15 older adults with SCD (predominantly Caucasian men and women, average age = 70) were randomly assigned to either an 8-week mindfulness training based on MBSR that was tailored for older adults, or a 5-week program that provided education on memory and aging, situational factors that affect memory, and strategies to compensate for memory difficulties. Participants completed self-report measures of memory complaints, depression, and mindfulness (the Five Facet Mindfulness Questionnaire, or FFMQ).

They also completed an attentional capacity task that required them to be vigilant and respond or withhold responding to letters presented on a computer screen. An electroencephalogram (EEG) recorded the magnitude of their brain’s P3 evoked response potentials (ERPs) while performing this task. Higher P3 ERPs reflect increased attentional capacity and are known to decrease in amplitude with SCD. All these measures were obtained both before and after intervention. Structural magnetic resonance imaging (MRI) was also included to detect changes in total brain volume from pre- to post- intervention.

Adults with SCD reported a greater number of subjective memory complaints and had a […]

May 19th, 2016|News|

Meditation aids attention of older adults, brain regions identified

Posted 02.24.2016 | by AMRA

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As we mature into old age, our ability to remain focused and quickly choose the correct response from a set of competing responses tends to diminish. Can mindfulness training help us retain our attention, executive control and emotional regulation as we age? Malinowski, et al [Mindfulness] randomly assigned mature adults to either mindfulness training or an active comparison group, and assessed the changes in their ability to perform a task that demanded focused attention, executive control, and emotional regulation while their brain activity was measured.

The researchers assigned a predominantly female cohort of 56 British older adults (average age = 64) to either mindfulness training or a “brain training” comparison condition. Mindfulness training entailed four 90-minute group-training sessions in breath-focused concentration meditation with instructions for maintaining a non-judgmental, non-elaborative attitude. Mindfulness trainees practiced meditation at home at least 10 minutes a day, five days a week, over 8 weeks.

The comparison condition met as a group for an equivalent amount of time. Both groups entailed psychoeducation, group discussion, and skills practice, but the “brain training” group practiced mental arithmetic instead of meditation, both in the groups and at home.

All participants completed the Five Facet Mindfulness Questionnaire (FFMQ) and a Stroop task, before and after training. The Stroop task required participants to count the number of words they saw that were presented on a computer screen. Sometimes the words’ meanings interfered with their counting (e.g., when the word “two” appeared three times) or had emotional connotations that could slow their processing speed. Participants needed to ignore the meanings and stay focused on the task.

Electroencephalography (EEG) concurrently measured the participants’ evoked response potentials (ERPs), which are […]

February 24th, 2016|News|

Wearable brain feedback technology to support mindfulness practice

Posted 10.30.2015 | by AMRA

The basic mindfulness instruction to “attend to the present moment without judgment” seems straightforward, but novices are often unsure whether they are practicing mindfulness “correctly.” There are no existing objective behavioral markers of mindfulness, and descriptions of what mindfulness “feels like” are often metaphorical (e.g., “spacious” or “intimate”) and hard to interpret.

This lends a hit-or-miss quality to training, and has led some to wonder whether neurofeedback (a form of biofeedback that uses electro-encephalogram (EEG) data to alter brain rhythms) might be a useful way to support mindfulness practice. Previous research has identified a group of EEG parameters (e.g., the appearance of alpha frequencies, increasing alpha amplitude, and a gradual shift towards lower alpha and theta frequencies) that accompany the meditative state. Neuro-feedback devices that help meditators achieve these EEG patterns may help assist in cultivating mindfulness.

Sas & Chopra [Personal and Ubiquitous Computing] developed a wearable mindfulness neurofeedback device (MeditAid) and tested it with novice and experienced meditators. The MeditAid prototype includes a wearable, wireless headset to record scalp EEGs and software to translate EEG patterns into auditory feedback. The auditory feedback is delivered as either monaural beats (sounds of differing frequencies presented to both ears simultaneously) or binaural beats (sounds of differing frequencies presented to each ear separately) through headphones. Each method produces a rhythmic pattern of beats that corresponds to the user’s EEG frequency.

The difference between monaural and binaural beats is that monaural beat perception is a function of the mechanics of the inner ear, whereas binaural beat perception is a function of the integrative activity of the brain. Listeners hear lower monaural and binaural beat frequencies as having a […]

October 30th, 2015|News|

Mothers’ mindfulness and infant brain development

Posted: 07.11.2014 | by AMRA

Previous studies have shown that expectant mothers’ anxiety and stress can adversely affect their children’s brain development. If this is so, is it possible that expectant mothers’ levels of mindfulness can have a positive, protective effect on their children’s brain development?

van den Heuvel et al. [Social Cognitive and Affective Neuroscience] tested this possibility by assessing mindfulness (using a short form of the Freiburg Mindfulness Inventory) and anxiety (using a symptom checklist) in 78 expectant mothers during the second trimester of pregnancy. Nine months after their infants were born, the research team assessed the infants’ auditory processing by measuring their brain’s electrical responsiveness to sounds, or “auditory evoked event related potentials” (ERPs) using an electroencephalogram (EEG) to measure this responsiveness.

The infants were presented with series of sounds: a frequently presented tone with a base frequency of 500 vibrations per second interspersed with less frequently presented sounds such as the sound of a door slamming or a dog barking. The researchers analyzed two waveform components of the infants’ brain responses to sounds: a “P150” component (an electrically positive component of an EEG wave occurring at approximately 150 milliseconds after the presentation of a sound) reflecting selective attention to a particular stimulus together with suppression of attention to other stimuli, and an “N250” component (an electrically negative component of an EEG wave occurring at approximately 250 milliseconds after the presentation of a sound) tied to turning one’s attention to a novel stimulus.

Mothers’ mindfulness during pregnancy was associated with significantly larger infant P150 wave amplitudes and significantly smaller infant N250 wave amplitudes. Maternal anxiety during pregnancy was associated with significantly larger infant N250 wave amplitudes. […]

July 11th, 2014|News|

MBCT and Emotional Processing in Bipolar

Posted: 01.12.2014 | by AMRA

Patients with bipolar disorder display irregularities in their emotional processing even when they appear overtly asymptomatic. Howells et al. [Metabolic Brain Disease] explored the impact of MBCT on biological markers of emotional processing irregularities in a cohort of stably remitted bipolar patients. Prior to receiving MBCT, 12 bipolar patients in remission were compared with 9 healthy controls. Both groups underwent a monitoring process of electrical activity of the brain (electroencephalography; EEG) and heart (electrocardiography; ECG) while completing tasks involving  matching  inanimate  objects,  matching facial  expressions, and  labeling emotions.

The bipolar patients showed exaggerated negative event-related potentials (ERPs) on their EEGs at approximately 170 milliseconds after stimulus exposure (ERP N170) and higher heart rate variability high frequency (HRV-HF) peaks on their ECGs. Both differences were especially significant during the facial expression matching task, which may reflect impaired communication between the cerebral cortex and the amygdala during emotional processing. This functional impairment may limit the ability of bipolar patients to control their affective reactivity, rendering them vulnerable to relapse.

The bipolar patients were then retested after completing an 8-week MBCT program, and they showed significant reduction in their exaggerated ERP N170 responses and their elevated HRV-HF peaks compared to their initial baseline measures. There was no change in bipolar symptoms observed after MBCT, probably reflecting the fact that participants were in stable remission. While these results are supportive of MBCT’s promise in treating the emotional processing deficits of bipolar patients, caution is needed in interpreting results due to limitations in this pilot study, including its small sample size, lack of repeated measures for the control group, and the unknown effects of patient medication on the physiological […]

January 27th, 2014|News|

Brief Meditation Shifts Frontal Brain Asymmetry to Promote Mood Regulation

Posted from archive: 03.26.2013 | by AMRA

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Keune et al. [Biological Psychology] studied the effects of mindfulness meditation on frontal EEG alpha wave asymmetry. It is generally held that relatively higher left frontal alpha power is associated with depression and avoidance motivation, whereas relatively higher right frontal alpha power is associated with approach motivation. While studies agree that mindfulness enhances relative right frontal alpha in healthy adults, the data for depressed adults is contradictory.

To clarify this, the authors measured frontal alpha asymmetry in 57 women with a history of recurrent depressive disorder. They recorded EEGs at baseline, after the induction of a sad mood, and after twenty minutes of either mindfulness meditation or a rumination challenge. In both the conditions, participants were told to focus on their breath, but one group received additional mindfulness instructions, while the other heard distracting instructions to ruminate, which they were told to try to ignore. Participants received no prior training in meditation.

In accord with previous studies, greater baseline left alpha power correlated with depressive symptoms, and greater baseline right alpha power correlated with positive mood. More importantly, mindfulness meditation shifted alpha activation toward the right and reduced negative affect, while there was no similar effect for the rumination challenge. The results support the theory that mindfulness shifts frontal asymmetry, promoting approach motivation and thereby facilitating mood regulation. The study was limited by nonrandom assignment to conditions.

Reference:

Keune, P. M., Bostanov, V., Hautzinger, M., & Kotchoubey, B. (2013). Approaching dysphoric mood: State-effects of mindfulness meditation on frontal brain asymmetry. Biological Psychology, 93(1),105-13. [PMID: 23410762]

[Link to abstract]

December 29th, 2013|News|

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