Page 152 - Migraine, the heart and the brain

Chapter 8
of the three migraineurs with aura actually had an attack with aura preceding the study. Mean duration between the end of the attack and rst testing was 17 hours (SD 6.9, range 5–27). The second test session took place 23.3 hours (SD 2.1, range 21–30) after the rst, and the third session 12 days (SD 14, range 3–70) after the second. Two participants suffered another migraine attack before the third visit, causing the third visit to be postponed.
Perceptual organization (global-local) task
Mean reaction times for the global-local task are shown in Table 3. Reaction times decreased with each session in both migraineurs and controls [F(2,27) =16.94, p < 0.0001] and congruence between the letters at the two levels (global and local) yielded faster responses than incongruence [F(1,28)= 81.56, p < 0.0001]. Neither Migraine group vs. controls nor global vs. local produced a main effect [F(1,28) < 1]. There was a migraine vs. controls-by-global vs. local interaction [F(1,28)4.99, p= 0.034]. The source of this interaction is shown in Figure 1: controls showed faster reaction time when responding to global than to local stimuli [t(1,15)= 3.86, p= 0.035 (one-tailed)], a replication of the standard global-precedence effect (14). Migraineurs actually showed a trend towards the opposite pattern with longer reaction times to global than to local stimuli, but this difference did not reach signi cance (p= 0.12). In other words, the standard globalprecedence effect was eliminated in migraine patients. Even though the gure suggests a modulation by session, there was no three-way interaction (p= 0.26) of global vs. local, migraine vs. controls, and session, suggesting that the difference between migraineurs and controls was statistically comparable across sessions. Interestingly, the interaction of group and level approached signi cance if only the prophylaxis-using migraineurs were considered (p=0.055) but was far from signi cance if non-prophylaxis users were compared with controls (p=0.2).
The one participant not using triptans did not perform differently compared to triptan users on the global-local test.
Table 1. Characteristics of participants
Female gender
Age (years)
Education moderate/high History of depression Current antidepressive use Migraine without aura
Migraine patients (n=16)
15 (94) 58 ± 9.1 9 (56) 4 (25) 2 (13) 13 (81)
Controls (n=18) p-value
15 (83) 0.6 59 ± 7.4 0.7 11 (61) 0.8 2 (11) 0.4 2 (11) 1.0 - NA
Values are n (%) or mean ± standard deviation. NA, not applicable.
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