In probabilistic cuing of visual search, participants search for a target object that appears more frequently in one region of the display. This task results in a search bias towards the rich quadrant compared with other quadrants. Previous research suggests that this bias is inflexible (difficult to unlearn) and implicit (participants are unaware of the biased distribution of targets). We tested these hypotheses in two preregistered, high-powered experiments (Ns = 160 and 162). In an initial biased stage, participants performed a standard probabilistic cuing task. In a subsequent unbiased stage, the target appeared in all quadrants with equal probability. Awareness questions were included after the biased stage in one group of participants, and after the unbiased stage in a second group. Results showed that participants were aware of the rich area and this effect was larger for the group whose awareness was assessed after the biased stage. In addition, analyses of visual search times indicated that the search bias towards the rich area (formed during the biased stage) was reduced during the unbiased stage. These results cast doubts on the characterization of probabilistic cuing as an implicit and inflexible 'search habit'.

Evaluative conditioning (EC) is one of the most widely-studied procedures for establishing and changing attitudes. The surveillance-task (Olson & Fazio, 2001) is a highly cited EC paradigm, and one that is claimed to generate attitudes without awareness. The potential for EC effects to occur without awareness continues to fuel conceptual, theoretical, and applied developments. Yet few published studies have used this task, and most are characterized by small samples and small effect sizes. We conducted a high-powered (N =1478), preregistered close replication of the original surveillance-task study. We obtained evidence for a small EC effect when ‘aware’ participants were excluded using the original criterion – therefore replicating the original effect. However, no such effect emerged when three other awareness criteria were used. We suggest that there is a need for caution when using evidence for the surveillance task effect to make theoretical and practical claims about ‘unaware’ EC effects.

Exogenous attention is a set of mechanisms that allow us to detect and reorient toward salient events-such as appetitive or aversive-that appear out of the current focus of attention. The nature of these mechanisms, particularly the involvement of the parvocellular and magnocellular visual processing systems, was explored. Thirty-four participants performed a demanding digit categorization task while salient (spiders or S) and neutral (wheels or W) stimuli were presented as distractors under two figure-ground formats: heterochromatic/isoluminant (exclusively processed by the parvocellular system, Par trials) and isochromatic/heteroluminant (preferentially processed by the magnocellular system, Mag trials). This resulted in four conditions: SPar, SMag, WPar, and WMag. Behavioral (RTs and error rates in the task) and electrophysiological (ERPs) indices of exogenous attention were analyzed. Behavior showed greater attentional capture by SMag than by SPar distractors and enhanced modulation of SMag capture as fear of spiders reported by participants increased. ERPs reflected a sequence from magnocellular dominant (P1p, ≃120 msec) to both magnocellular and parvocellular processing (N2p and P2a, ≃200 msec). Importantly, amplitudes in one N2p subcomponent were greater to SMag than to SPar and WMag distractors, indicating greater magnocellular sensitivity to saliency. Taking together, results support a magnocellular bias in exogenous attention toward distractors of any nature during initial processing, a bias that remains in later stages when biologically salient distractors are present.

People usually become faster at finding a visual target after repeated exposure to the same search display. This effect, known as contextual cueing, is often thought to rely on a highly efficient learning mechanism, relatively unconstrained by the availability of attentional resources. Consistent with this view, experimental evidence suggests that contextual cueing can be found even when participants are instructed to ignore the repeated visual context, although this learning remains latent until the context receives full attention. The present study explores the contribution of selective attention to contextual cueing in four high-powered preregistered experiments. None of them supported the hypothesis that latent learning can occur without selective attention. In general, our results suggest that selective attention to visual context plays an essential role in both the acquisition and the expression of contextual cueing.

In fear conditioning, more efficient sensory processing of a stimulus (the conditioned stimulus, CS) that has acquired motivational relevance by being paired with an aversive event (the unconditioned stimulus, US) has been associated with increased cortical gain in early sensory brain areas (Miskovic and Keil, 2012). Further, this sensory gain modulation related to short-term plasticity changes occurs independently of aware cognitive anticipation of the aversive US, pointing toward implicit learning mechanisms (Moratti and Keil, 2009). However, it is unknown how quickly the implicit learning of CS-US associations results in the adaptation of cortical gain. Here, using steady-state visually evoked fields derived from human Magnetoencephalography (MEG) recordings in two experiments ( = 33, 17 females and 16 males), we show that stimulus-driven neuromagnetic oscillatory activity increases and decreases quickly as a function of associative strength within three or four trials, as predicted by a computationally implemented Rescorla-Wagner model with the highest learning rate. These ultrafast cortical gain adaptations are restricted to early visual cortex using a delay fear conditioning procedure. Short interval (500 ms) trace conditioning resulted in the same ultrafast activity modulations by associative strength, but in a complex occipito-parieto-temporo-frontal network. Granger causal analysis revealed that reverberating top-down and bottom-up influences between anterior and posterior brain regions during trace conditioning characterized this network. Critically, in both delay and trace conditioning, ultrafast cortical gain modulations as a function of associative strength occurred independently of conscious US anticipation. In ever-changing environments, learned associations between a cue and an aversive consequence must change under new stimulus-consequence contingencies to be adaptive. What predicts potential dangers now might be meaningless in the next situation. Predictive cues are prioritized, as reflected by increased sensory cortex activity for these cues. However, this modulation also must adapt to altered stimulus-consequence contingencies. Here, we show that human visual cortex activity can be modulated quickly according to ultrafast contingency changes within a few learning trials. This finding extends to frontal brain regions when the cue and the aversive event are separated in time. Critically, this ultrafast updating process occurs orthogonally to aware aversive outcome anticipation and therefore relies on unconscious implicit learning mechanisms.