Visual verbal working memory processing may be interfered by previously seen faces.
Processing and maintenance in working memory involve active attention allocation; consequently, it is possible that a recognition process could interfere with the performance of highly demanding working memory tasks. Event-related brain potentials (ERPs) were recorded while fourteen healthy male adults performed a visual verbal dual working memory task. Three conditions were examined: A) reference (with no preceding stimuli); B) happy, angry or neutral faces presented 250 ms prior to task onset for 30 ms; and, C) visual noise control condition. Behavioral results showed that reaction times were significantly longer in the condition preceded by the presentation of faces, regardless of their emotional content. ERPs showed a predominantly right temporo-occipital negative component at around 170 ms during conditions B and C (higher amplitude in B), which probably reflects the pre-categorical structural encoding of the face. Succeeding task-onset, an early positive right temporo-parietal component (P380) appeared during condition B, probably reflecting a delayed reallocation of working memory attentional resources to carry out the task requirements. Afterwards, two other main fronto-parietal components were observed in the three conditions: a positive wave that peaked at around 410 ms, and a subsequent negative component (N585). This latter waveform reached a significantly higher amplitude during the reference condition (A) and was interpreted as mirroring the phonologic-lexical manipulation of the stimuli in working memory. These results suggest that early face detection could induce an attentional decrement that interfere a subsequent visual verbal working memory task performance. They also suggest that while face detection and facial emotional content analysis might be parallel processes, they are not onset-synchronized.
Gonzalez-Garrido
Andres A
AA
Instituto de Neurociencias, Universidad de Guadalajara, México.
Ramos-Loyo
Julieta
J
Gomez-Velazquez
Fabiola R
FR
Alvelais Alarcón
Marina
M
Moises de la Serna Tuya
Juan
J
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D003265:Contingent Negative Variation / Q000502:physiology; D004644:Emotions / Q000502:physiology; D005145:Face; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology