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Explicit behavioral detection of visual changes develops without their implicit neurophysiological detectability.

Lyyra P, Wikgren J, Ruusuvirta T, Astikainen P - Front Hum Neurosci (2012)

Bottom Line: The participants attempted to explicitly (via voluntary button press) detect the occasional change.Nevertheless, prior to this point of explicit detectability, the implicit detection of the changes vMMN could only be observed with the 100 ms intervals.These findings of explicit change detection developing with and without implicit change detection may suggest that the two modes of change detection recruit independent neural mechanisms.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Jyväskylä Jyväskylä, Finland.

ABSTRACT
Change blindness is a failure of reporting major changes across consecutive images if separated, e.g., by a brief blank interval. Successful change detection across interrupts requires focal attention to the changes. However, findings of implicit detection of visual changes during change blindness have raised the question of whether the implicit mode is necessary for development of the explicit mode. To this end, we recorded the visual mismatch negativity (vMMN) of the event-related potentials (ERPs) of the brain, an index of implicit pre-attentive visual change detection, in adult humans performing an oddball-variant of change blindness flicker task. Images of 500 ms in duration were presented repeatedly in continuous sequences, alternating with a blank interval (either 100 ms or 500 ms in duration throughout a stimulus sequence). Occasionally (P = 0.2), a change (referring to color changes, omissions, or additions of objects or their parts in the image) was present. The participants attempted to explicitly (via voluntary button press) detect the occasional change. With both interval durations, it took 10-15 change presentations in average for the participants to eventually detect the changes explicitly in a sequence, the 500 ms interval only requiring a slightly longer exposure to the series than the 100 ms one. Nevertheless, prior to this point of explicit detectability, the implicit detection of the changes vMMN could only be observed with the 100 ms intervals. These findings of explicit change detection developing with and without implicit change detection may suggest that the two modes of change detection recruit independent neural mechanisms.

No MeSH data available.


Related in: MedlinePlus

Grand averaged difference waves (change—no change) during change blindness running from stimulus onset (0 ms) to 300 ms post-stimulus.
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Figure 2: Grand averaged difference waves (change—no change) during change blindness running from stimulus onset (0 ms) to 300 ms post-stimulus.

Mentions: A prominent differential ERP for the unnoticed changes of negative polarity is observable in the grand averaged waveforms (see Figures 2 and 3) in the posterior and posterio-temporal electrode sites (P7, P8, Oz, O1, O2), especially in the condition of 100 ms ISI. These differential ERPs resembled in their latency, scalp topography, and stimulus and attentive conditions the visual analog of the mismatch negativity (MMN) of ERPs (Pazo-Alvarez et al., 2003; Czigler, 2007). For assessing response amplitudes, a time window of 200–260 ms (for vMMN, see e.g., Astikainen et al., 2008; Pazo-Alvarez et al., 2003; for change blindness studies, see Fernandez-Duque et al., 2003; Schankin and Wascher, 2007, 2008; Kimura et al., 2008) was selected for which mean values from each electrode were extracted. The resultant values were submitted to a repeated measures multivariate analysis of variance (MANOVA), Electrode site (P7, P8, Oz, O1, O2) and Stimulus type (No change, Change) as within-subject factors in each ISI condition (100 ms and 500 ms). This is due to two things. First, a response to the presentation of the blank screen is visible in the pre-stimulus period of the ERPs of the 100 ms ISI condition suppressing their amplitudes (see Figure 3), which makes the conditions differ slightly in functional terms with respect to each other. Second, the subjects are only partly same in both conditions, so they cannot be incorporated in the same statistical model. Only results involving Change as a factor are reported here.


Explicit behavioral detection of visual changes develops without their implicit neurophysiological detectability.

Lyyra P, Wikgren J, Ruusuvirta T, Astikainen P - Front Hum Neurosci (2012)

Grand averaged difference waves (change—no change) during change blindness running from stimulus onset (0 ms) to 300 ms post-stimulus.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3300035&req=5

Figure 2: Grand averaged difference waves (change—no change) during change blindness running from stimulus onset (0 ms) to 300 ms post-stimulus.
Mentions: A prominent differential ERP for the unnoticed changes of negative polarity is observable in the grand averaged waveforms (see Figures 2 and 3) in the posterior and posterio-temporal electrode sites (P7, P8, Oz, O1, O2), especially in the condition of 100 ms ISI. These differential ERPs resembled in their latency, scalp topography, and stimulus and attentive conditions the visual analog of the mismatch negativity (MMN) of ERPs (Pazo-Alvarez et al., 2003; Czigler, 2007). For assessing response amplitudes, a time window of 200–260 ms (for vMMN, see e.g., Astikainen et al., 2008; Pazo-Alvarez et al., 2003; for change blindness studies, see Fernandez-Duque et al., 2003; Schankin and Wascher, 2007, 2008; Kimura et al., 2008) was selected for which mean values from each electrode were extracted. The resultant values were submitted to a repeated measures multivariate analysis of variance (MANOVA), Electrode site (P7, P8, Oz, O1, O2) and Stimulus type (No change, Change) as within-subject factors in each ISI condition (100 ms and 500 ms). This is due to two things. First, a response to the presentation of the blank screen is visible in the pre-stimulus period of the ERPs of the 100 ms ISI condition suppressing their amplitudes (see Figure 3), which makes the conditions differ slightly in functional terms with respect to each other. Second, the subjects are only partly same in both conditions, so they cannot be incorporated in the same statistical model. Only results involving Change as a factor are reported here.

Bottom Line: The participants attempted to explicitly (via voluntary button press) detect the occasional change.Nevertheless, prior to this point of explicit detectability, the implicit detection of the changes vMMN could only be observed with the 100 ms intervals.These findings of explicit change detection developing with and without implicit change detection may suggest that the two modes of change detection recruit independent neural mechanisms.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Jyväskylä Jyväskylä, Finland.

ABSTRACT
Change blindness is a failure of reporting major changes across consecutive images if separated, e.g., by a brief blank interval. Successful change detection across interrupts requires focal attention to the changes. However, findings of implicit detection of visual changes during change blindness have raised the question of whether the implicit mode is necessary for development of the explicit mode. To this end, we recorded the visual mismatch negativity (vMMN) of the event-related potentials (ERPs) of the brain, an index of implicit pre-attentive visual change detection, in adult humans performing an oddball-variant of change blindness flicker task. Images of 500 ms in duration were presented repeatedly in continuous sequences, alternating with a blank interval (either 100 ms or 500 ms in duration throughout a stimulus sequence). Occasionally (P = 0.2), a change (referring to color changes, omissions, or additions of objects or their parts in the image) was present. The participants attempted to explicitly (via voluntary button press) detect the occasional change. With both interval durations, it took 10-15 change presentations in average for the participants to eventually detect the changes explicitly in a sequence, the 500 ms interval only requiring a slightly longer exposure to the series than the 100 ms one. Nevertheless, prior to this point of explicit detectability, the implicit detection of the changes vMMN could only be observed with the 100 ms intervals. These findings of explicit change detection developing with and without implicit change detection may suggest that the two modes of change detection recruit independent neural mechanisms.

No MeSH data available.


Related in: MedlinePlus