Dissociable rhythmic mechanisms enhance memory for conscious and nonconscious perceptual contents.

Understanding the neural mechanisms of conscious and unconscious experience is a major goal of fundamental and translational neuroscience. Here, we target the early visual cortex with a protocol of noninvasive, high-resolution alternating current stimulation while participants performed a delayed target-probe discrimination task and reveal dissociable mechanisms of mnemonic processing for conscious and unconscious perceptual contents. Entraining ß-rhythms in bilateral visual areas preferentially enhanced short-term memory for seen information, whereas α-entrainment in the same region preferentially enhanced short-term memory for unseen information. The short-term memory improvements were frequency-specific and long-lasting. The results add a mechanistic foundation to existing theories of consciousness, call for revisions to these theories, and contribute to the development of nonpharmacological therapeutics for improving visual cortical processing.

Anxiety and Avoidance in Close Relationships Are Associated With Responses to Negative and Positive Stimuli.

Humans tend to assign valence to objects, people, and events in the environment, but there are individual differences in the evaluation of the affective nature of these environmental stimuli. This exploratory study investigated how individual differences in anxiety and avoidance in close relationships are associated with the emotional appraisal of valenced and neutral stimuli. Participants evaluated negative, neutral, and positive stimuli for emotional valence in an image classification task. There was a positivity offset across all participants, in that neutral stimuli were evaluated as more positive than negative. Individuals higher on the Experiences in Close Relationships-Anxiety subscale showed a negativity bias in reaction times and ratings: they had faster response times to negative than to positive stimuli and had a greater tendency to evaluate positive stimuli as "negative." Individuals higher on the Experiences in Close Relationships-Avoidance subscale gave more positive ratings of negative stimuli and more negative ratings of positive stimuli, which may suggest a general blunted response to emotional stimuli. Findings are discussed in the context of the literature on individual differences and emotional appraisal of stimuli.