Table 4.
Summary of the studies which included P300 component
| Study | Study Groups | Paradigm | Findings |
|---|---|---|---|
| [17] | 20 Israeli combat veterans with PTSD 20 without PTSD |
Modified target detection visual oddball paradigm, trauma related non-related neutral stimuli |
Accentuated P300 amplitudes to target stimuli in both controls and PTSD patients Enhanced P300 amplitude in response to non-target combat related pictures in PTSD group Prolonged P300 latencies and reaction times to target stimuli were prolonged in PTSD subjects Increased latency in response to trauma-related stimuli in PTSD subjects |
| [50] | 20 Israeli veterans with PTSD 20 without PTSD |
Modified target detection visual oddball paradigm, trauma related, unrelated, neutral pictures |
Smaller response to non-target images in the control, but equal responses to both target and non-target stimuli in the PTSD group No group difference for the target stimuli, but larger response to the non-target in the PTSD group. P300 could correctly classify 90% of PTSD and 90% of non-PTSD subjects. Increased latency of P300 response to combat-related images in relation with the severity of intrusive symptoms. This relation was negative between the P300 latency and severity of avoidance. |
| [58] | 20 PTSD combat veterans 20 non-PTSD combat veterans |
Target detection oddball, traumatic/neutral stimuli | Larger P300 amplitude in the PTSD group No difference inP300 amplitude between the target and non-target in the PTSD group; higher amplitude in response to the target stimuli in the control group. Earlier and 5 times greater P300 response to combat related pictures in PTSD patients. Repeated combat related pictures resulted in a rapid P300 amplitude reduction and latency prolongation. This effect was not observed for the target stimuli. |
| [59] | 19 civil PTSD 17 subjects with numerous life events 18 without life events |
Auditory oddball | Longer reaction times and lower amplitude P300 response |
| [60] | 8 PTSD 8 non-PTSD combat veterans |
Visual presentation of a sequence of trauma related and unrelated words | Newly identified P300tr component was suppressed to all stimuli in PTSD subjects |
| [43] | 34 PTSD [25 male veterans/9 female victims of rape] 18 non-PTSD [10/8 from the same groups] |
Auditory three-tone oddball | Smaller P300 response to the target tone. For women group, it was also smaller in response to the distracter tones. |
| [41] | 9 PTSD [assault, rape, MVA, combat] 10 healthy controls |
Modified stroop paradigm, visual presentation of neutral, positive and negative words | Smaller P300 amplitude to neutral, positive, and negative words in PTSD patients. Smaller response to neutral words as compared to positive and negative words. |
| [56] | 16 medicated PTSD 9 un-medicated PTSD 10 healthy veterans |
Auditory three-tone oddball | Significant decrease in P300 at Pz electrode in un-medicated PTSD group compared to the medicated PTSD and healthy subjects. Subjects with co-morbid panic disorder had the largest P300 amplitudes. |
| [39] | 11 survivors of a ship fire with PTSD or near PTSD 9 controls with other psychiatric illnesses from the same ship |
Auditory word and non-word oddball | Reduced P300 amplitude to non-words and negative words |
| [61] | 25 combat veterans with PTSD/14 without PTSD | Auditory three-tone oddball | Reduced P300 amplitude to the target stimuli. Significant P300 amplitude enhancements at frontal sites to distracting stimuli during the novelty but not during the three-tone oddball tasks. |
| [62] | 10 Vietnam war veterans with PTSD 10 without PTSD |
Two oddball tasks of visual trauma-relevant and trauma-irrelevant threat (combat, social-threat, household, and neutral words) | Attenuated P300 response to neutral target stimuli Increased P300 amplitude in response to trauma-relevant combat stimuli but not to trauma-irrelevant social-threat stimuli at frontal electrode sites. |
| [28] | 17 civil PTSD 17 healthy controls |
Auditory oddball | Smaller P300 in PTSD, later at Pz |
| [32] | 29 PTSD nurse veterans 38 non-PTSD |
Three-tone oddball | Larger target P300 amplitudes in PTSD subjects |
| [38] | 15 civil PTSD 15 controls |
20 angry and 20 neutral faces | Slower P270 in the PTSD at occipital electrodes |
| [63] | 25 combat PTSD 15 combat-exposed healthy controls |
Three conditioned novelty visual and auditory oddball | No significant differences in P300 amplitude or latency regardless of stimulus type (target, novel) or modality (auditory, visual). |
| [35] | 10 civil PTSD 10 controls |
Auditory oddball | Same P3a amplitude in both groups, but there was a significant post-treatment attenuation of P3a in the PTSD group. |
| [64] | 8 PTSD victims of Tokyo sarin attack 13 healthy controls |
Auditory oddball | No difference in P300 latency. Significantly smaller P300 amplitudes in subjects with PTSD. |
| [65] | 33 civil PTSD 33 matched controls |
Auditory standard two-tone oddball | Delayed reduced P300 target amplitude, coupled with slower and less accurate target detection |
| [12] | 10 male police/veteran PTSD 10 healthy controls |
Auditory oddball | Smaller P550; More false negatives and positives; The higher the anxiety and depression level, the lower the amplitude; Reverse relationship between the P550 amplitude and intrusions. |
| [42] | 19 PTSD 99 Alcohol dependence 16 personality disorder 25 anxiety or mood disorder |
Visual presentation of happy, sad, and neutral faces | Longer P300 latency to happy stimuli in midline, central, and right frontal leads; Reduced P300 amplitude in response to neutral faces. |
| [40] | 16 civil PTSD 15 trauma-exposed without PTSD 16 healthy controls |
Modified auditory S1-S2 paradigm | Increased P300 and late positive complex amplitudes to trauma-specific questions; Only the PTSD group showed a differentiation between trauma-specific and neutral questions with respect to P300. |
| [66] | 14 PTSD survivors of an air show disaster 15 trauma-exposed subjects without PTSD 15 healthy controls |
Visual differential conditioning paradigm with traumatic/neutral pictures | Trauma-exposed subjects with and without PTSD showed successful differential conditioning to the trauma-relevant cue indicative of second-order conditioning |
| [57] | 16 civil PTSD 16 schizophrenia 16 control subjects |
Auditory oddball | Reduced amplitude of target and non-target P300 responses. Larger reduction in target P300 amplitude in left posterior parietal leads in PTSD group. |
| [49] | 37 combat exposed veterans with PTSD and 47 without PTSD and their twins | Auditory oddball | No difference in P300 amplitude; When assessed the un-medicated nonsmoker group separately, P300 amplitude was smaller in the PTSD group |
| [1] | 20 un-medicated and 14 medicated PTSD [mixed etiology] 136 controls |
1-back working memory task | Reduced P300 working memory amplitude and delayed target P300 in PTSD. Amplitude reduction and delay of target P300 in medicated PTSD subjects. Little difference between the non-medicated PTSD subgroup and the controls. |
| [34] | 12 PTSD and 12 control survivors of earthquake | Subliminal visual presentation of earthquake-related/unrelated words | Increased P2 and P3 amplitude in the PTSD group in response to the trauma-related stimuli |