Table 3: Details of event related studies.

S. numberCitationParticipantsNature of the ERP taskDesignInterventionFindings

1Neuroscience. 2014, 281C: 195–201 [31]Healthy experienced meditators and nonmeditators Affective picture viewingTwo-group studyNo intervention was given but this study compared between long-term experienced Sahaja yoga meditators and nonmeditatorsMid latency (140–400 ms)
ERPs were attenuated for both positive and negative pictures and a stronger ERP negativity in the time window 200–300 ms was found in meditators regardless of picture valence. We assume that long-term meditation practice enhances frontal top-down control over fast automatic salience detection, based on amygdala functions.

2Int J Psychophysiol. 2013, 90 (2): 207–214 [32]Healthy experienced meditators aged 20–61 yearsAuditory oddball task with two tones (standard and target)One group was assessed in two separate conditions (self as control)Vipassana meditation and random thinkingThe Vipassana experts showed greater P3b amplitudes to the target tone after meditation than they did both before meditation and after the no-meditation session. These results suggest that expert Vipassana meditators showed increased attentional engagement after meditation.

3Soc Cogn Affect Neurosci. 2013, 8 (1): 100–111 [34]Healthy Vipassana meditators Exp. = 2.5–40 yearsThree-stimulus auditory oddball taskOne group was assessed in two separate conditions (self as control)Vipassana meditation and instructed mind wanderingMeditation compared to control condition had decreased evoked delta (2–4 Hz) power to distracter stimuli concomitantly with a greater event-related reduction of late (500–900 ms) alpha-1 (8–10 Hz) activity, which indexed altered dynamics of attentional engagement to distracters. Additionally, standard stimuli were associated with increased early event-related alpha phase synchrony (intertrial coherence) and evoked theta (4–8 Hz) phase synchrony, suggesting enhanced processing of the habituated standard background stimuli. Finally, during meditation, there was a greater differential early-evoked gamma power to the different stimulus classes. Correlation analysis indicated that this effect stemmed from a meditation state-related increase in early distracter-evoked gamma power and phase synchrony specific to longer-term expert practitioners. The findings suggest that Vipassana meditation evokes a brain state of enhanced perceptual clarity and decreased automated reactivity.

4Front Hum Neurosci. 2012, 6: 133 [38]Healthy meditators and nonmeditatorsGlobal-to-local target taskStudy conducted in two phases
Phase 1: cross sectional study
Phase 2: longitudinal study
Open monitoring meditationMeditators showed an enhanced processing of target level information. In contrast with control group, which showed a local target selection effect only in the P1 and a global target selection effect in the P3 component, meditators showed effects of local information processing in the P1, N2, and P3 and of global processing for the N1, N2, and P3. Thus, meditators seem to display enhanced depth of processing.
In the longitudinal experiment, meditation modulates attention already after a 4-day meditation retreat. Together, these results suggest that practicing meditation enhances the speed with which attention can be allocated and relocated, thus increasing the depth of information processing and reducing response latency

5Soc Cogn Affect Neurosci. 2013, 8 (1): 85–92 [45]Healthy meditators and nonmeditatorsStroop taskTwo-group studyComparison between meditators and nonmeditators, meditators are from various traditions Meditators showed greater executive control (i.e., fewer errors), a higher error related negativity (ERN), and more emotional acceptance than controls.

6BMC Psychiatry. 2012, 12: 15 [44]Patients with bipolar disorder and normal healthy participantsA visual A-X continuous performance taskTwo-group studyMindfulness based cognitive therapy (MBCT)MBCT in bipolar disorder improved attentional readiness and attenuated activation of nonrelevant information processing during attentional processes

7J Neural Eng. 2011, 8 (2): 025019 [42]Healthy individualsRow/column speller taskTwo-group studyMeditative Mindfulness Induction (MMI) and non-MMI control groupMMI subjects were significantly more accurate than control subjects and they produced significantly larger P300 amplitudes than control subjects at Cz and PO7

8Neurosci Res. 2011, 71 (1): 44–48 [46]Healthy meditators and nonmeditatorsEmotional load of stimuli (IAPS pictures)Two-group studyNo intervention was given but this study compared with experienced meditators and nonmeditatorsThe result showed different emotional processing in meditation practitioners: at high levels of processing meditators are less affected by stimuli with adverse emotional load, while processing of positive stimuli remains unaltered

9Pain. 2010, 150 (3): 428–438 [47]Healthy meditators and nonmeditatorsAnticipatory and pain-evoked ERPsTwo-group studyNo intervention was given but this study compared with experienced meditators and nonmeditators; meditators were from different traditionsMeditation reduces the anticipation and negative appraisal of pain

10J Neurosci. 2009, 29 (42): 13418–13427 [37]Healthy meditators and nonmeditatorsAttention blink task and attention auditory taskTwo-group studyVipassana and loving kindness meditationThree months of intensive meditation training reduced variability in attentional processing of target tones and reduced reaction time variability. Those individuals with greatest increase in neural response consistency had largest decrease in behavioral response variability. Reduced variability in neural processing was observed regardless of whether the deviant tone was attended or unattended. significantly affect attention and brain function.

11Conf Proc IEEE Eng Med Biol Soc. 2008, 2008: 662–665. [48] Meditators and nonmeditatorsDiscrimination of the imaginative hand movement and the idle stateTwo-group study Type of meditation not specifiedThe meditation practice can improve the classification accuracy of EEG patterns. The average classification accuracy was 88.73% in the meditation group, while it was 70.28% in the control group. An accuracy as high as 98.0% was achieved in the meditation group.

12Int J Psychophysiol. 2009, 72 (1): 51–60. [33]Healthy experienced meditatorsAuditory oddball task with two tones (standard and target)One group was assessed in two separate conditions (self as control)Vipassana meditation and random thinkingDuring meditation N1 amplitude from the distracter was reduced frontally; P2 amplitudes from both the distracter and oddball stimuli were somewhat reduced; P3a amplitude from the distracter was reduced. The meditation-induced reduction in P3a amplitude had a positive correlation with the quality and experience of meditation

13J Cogn Neurosci. 2009, 21 (8): 1536–1549. [36]Healthy meditators and nonmeditatorsThe attentional blink taskTwo-group studyVipassana
Meditation
Theta phase locking in conscious target perception and suggest that after mental training the cognitive system is more rapidly available to process new target information. Mental training was not associated with changes in the amplitude of T2-induced responses or oscillatory activity before task onset

14Neuroreport. 2007, 18 (16): 1709–1712. [39]Healthy meditators and nonmeditatorsThe mismatch negativity (MMN) paradigm Two-group studySudarshan kriya yoga meditationMeditators were found to have larger MMN amplitudes than nonmeditators. The meditators also exhibited significantly increased MMN amplitudes immediately after meditation suggesting transient state changes owing to meditation.

15PLoS Biol. 2007, 5 (6): e138. [35]Healthy meditators and nonmeditatorsThe attentional blink taskTwo-group studyVipassana Three months of intensive mental training resulted in a smaller attentional blink and reduced brain-resource allocation to the first target, as reflected by a smaller T1-elicited P3b, a brain-potential index of resource allocation. Those individuals that showed the largest decrease in brain-resource allocation to T1 generally showed the greatest reduction in attentional blink size. These observations provide novel support for the view that the ability to accurately identify T2 depends upon the efficient deployment of resources to T1. The results also demonstrate that mental training can result in increased control over the distribution of limited brain resources.

16Int J Neurosci. 2006, 116 (12): 1419–1430. [43]Healthy individuals Auditory oddball task with two tones (standard and target)One group was assessed in two separate conditions (self as control)Cyclic meditationThere was reduction in the peak latencies of P300 after cyclic meditation at Fz, Cz, and Pz compared to the “pre” values. The P300 peak amplitudes after CM were higher at Fz, Cz, and Pz sites compared to the “pre” values.

17Chin Med Sci J. 1999, 4 (2): 75–79. [40]Healthy meditators and nonmeditatorsThe auditory mismatch negativity (MMN) and P300Two-group studyMusical meditationMMN amplitudes in the trained children were larger than those in the control group. In addition, the MMN amplitudes were identical in attend and ignore conditions for both groups.