Blocking under stress: Sustained attention to stimuli without predictive value?

Blocking under stress: Sustained attention to stimuli without predictive value? Neurobiol Learn Mem. 2020 Jan 03;:107158 Authors: Magdalena Kausche F, Schwabe L Abstract Learning is blocked when a stimulus is followed by an outcome that is identical to what was expected and thus contains no new information. This classic 'blocking' effect exemplifies that learning is driven by the predictive value of stimuli, which in turn should guide the allocation of attentional resources. Stress is known to be a powerful modulator of learning and memory. However, whether stress may affect attentional processing during predictive learning is largely unknown. Here, we combined electroencephalography and eye-tracking with an experimental stress manipulation and a fear conditioning paradigm designed to probe the blocking effect, to determine if and how stress impacts efficient attentional processing during predictive learning. Participants' explicit ratings indicated, irrespective of stress, a blocking effect. The control group further showed preferential attentional processing of predictive vs. unpredictive stimuli, reflected in differential fixation durations and a differential N2pc. Stress abolished this differentiation and led even to sustained attention, indicated by higher late positive potentials, to stimuli with low predictive value. Moreover, stress resulted in an overall increase in the P3b during the blocking phase, suggesting increased att...
Source: Neurobiology of Learning and Memory - Category: Neurology Authors: Tags: Neurobiol Learn Mem Source Type: research