Frutas deshidratadas

Cued Uncued

* *

43

FIGURE 3B. Reaction Times as measured across strong endogenous-weak exogenous condition and weak endogenous-strong exogenous condition (exogenous attention plotted on the x-axis). 520 530 540 550 560 570 580 590 600 Cued Uncued R e ac tion Ti m e s (m s)

Reaction Times across conditions

Valid Invalid

* *

44

FIGURE 4. Topographies of amplitudes for the P1 peak for right and left targets at 125 ms at contra-lateral electrodes.

Topography of peak P1 amplitude to right targets

Topography of peak P1 amplitude to left targets

A20/P07

45 FIGURE 5. P1 component mean amplitudes

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Valid Cued Valid Uncued Invalid Cued Invalid Uncued

A m p litu d e s (µ V) Condition Types

P1 component (110 - 140 ms)

46

FIGURE 6A. ERPs of exogenously cued and uncued targets at the endogenously valid

location at the contralateral electrode (amplitudes combined across P07 and P08 electrodes). The ERP waveforms shown are collapsed across strong endogenous-weak exogenous condition and weak endogenous-strong exogenous condition.

Onset of target N1 P1  Valid Cued  ValidUncued Uncued

47

FIGURE 6B. ERPs of exogenously cued and uncued targets at the endogenously invalid

location at the contralateral electrode (amplitudes combined across P07 and P08 electrodes). The ERP waveforms shown are collapsed across strong endogenous-weak exogenous condition and weak endogenous-strong exogenous condition.

 Invalid Cued

 Invalid Uncued

48

FIGURE 6C. ERPs of endogenously valid and invalid targets at the exogenously cued

location at the contralateral electrode (amplitudes combined across P07 and P08 electrodes). The ERP waveforms shown are collapsed across strong endogenous-weak exogenous condition and weak endogenous-strong exogenous condition.

Onset of target

 Valid Cued  Invalid Cued

49

FIGURE 6D. ERPs of endogenously valid and invalid targets at the exogenously uncued

location at the contralateral electrode (amplitudes combined across P07 and P08 electrodes). The ERP waveforms shown are collapsed across strong endogenous-weak exogenous condition and weak endogenous-strong exogenous condition.

 Valid Uncued  Invalid Uncued

50

Figure 7. ERP waveforms at the central-posterior electrode CPz showing the P300 component (380-440 ms). The ERPs shown are collapsed across strong endogenous-weak exogenous condition and weak endogenous-strong exogenous condition.

Onset of target  Valid Cued  Valid Uncued  Invalid Cued  Invalid Uncued A32/CPz

51

TABLE 1. Means and Standard Errors of the mean of behavioral reaction times collapsed across conditions. Endogenous Attention Valid Invalid Exogenous Cued 544.25± 10.74 560.05±12.05 552.15±11.14 Attention Uncued 558.00±11.15 585.29±12.96 571.64±11.94 551.12±10.90 572.67±12.43

52

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