Multivariate pattern analysis of event-related potentials predicts the subjective relevance of everyday objects.

Potentially decision-relevant stimuli have been proposed to undergo immediate semantic processing. The current study investigated whether information regarding the general desirability ('Wanting') of visually presented 'everyday' objects was rapidly and automatically processed. Participants completed a foreground task while their electroencephalogram (EEG) was recorded, and task-irrelevant images were presented in the background. Following this, participants rated the images with regards to Wanting and the potentially related attributes of Relevance, Familiarity, Aesthetic Pleasantness and Time Reference. Multivariate pattern classification was used to predict the ratings from patterns of EEG data. Prediction of Wanting and Relevance was possible between 100 and 150ms following stimulus presentation. The other dimensions could not be predicted. Wanting and Relevance ratings were highly correlated and displayed similar feature weight maps. The current results suggest that the general desirability and subjective relevance of everyday objects is rapidly and automatically processed for a wide range of visual stimuli.

Action-related auditory ERP attenuation is not modulated by action effect relevance.

Event-related potentials (ERPs) elicited by self-induced sounds are often smaller than ERPs elicited by identical, but externally generated sounds. This action-related auditory ERP attenuation is more pronounced when self-induced sounds are intermixed with similar sounds generated by an external source. The current study explored whether attentional factors contributed to this phenomenon. Participants performed tone-eliciting actions, while the action-tone contingency and the set of additional action effects (tactile only, tactile and visual) were manipulated in a blocked manner. Previous action-tone contingence-effects were replicated, but the addition of other sensory action consequences did not influence the magnitude of auditory ERP attenuation. This suggests that the amount of attention allocated to concurrent non-auditory action effects does not substantially affect the magnitude of action-related auditory ERP attenuation and is on a par with the assumption that action-related auditory ERP attenuation might be related to the process of distinguishing self-induced stimuli from externally generated ones.

Decision Making and Oddball Effects on Pupil Size: Evidence for a Sequential Process.

In our physical environment as well as in many experimental paradigms, we need to decide whether an occurring stimulus is relevant to us or not; further, stimuli have uneven probabilities to emerge. Both, decision making and the difference between rare and frequent stimuli (oddball effect) are described to affect pupil dilation. Surprisingly though, conjoint systematic pupillometric investigations into both factors are still rare. In two experiments, both factors as well as their interplay were investigated. Participants completed a sequential letter matching task. In this task, stimulus probability and letter matching (decision making) were manipulated independently. As dependent variables, pupil dilation and reaction time were assessed. Results suggest a clearly larger pupil dilation for target than for distractor letters, even when targets were frequent and distractors rare. When considering the data structure best, no main effect of stimulus probability was found, instead, oddball effects only emerged when stimuli were goal-relevant to participants. The results are discussed in the light of common theoretical concepts of decision making and stimulus probability. Finally, relating theories of each factor, we propose an integrated framework for effects of decision making and stimulus features on pupil dilation. We assume a sequential mechanism during which incoming stimuli are decided upon regarding their goal relevance and, about 200 ms later, relevant stimuli are appraised regarding their value.

Stimulus relevance modulates contrast adaptation in visual cortex.

A general principle of sensory processing is that neurons adapt to sustained stimuli by reducing their response over time. Most of our knowledge on adaptation in single cells is based on experiments in anesthetized animals. How responses adapt in awake animals, when stimuli may be behaviorally relevant or not, remains unclear. Here we show that contrast adaptation in mouse primary visual cortex depends on the behavioral relevance of the stimulus. Cells that adapted to contrast under anesthesia maintained or even increased their activity in awake naïve mice. When engaged in a visually guided task, contrast adaptation re-occurred for stimuli that were irrelevant for solving the task. However, contrast adaptation was reversed when stimuli acquired behavioral relevance. Regulation of cortical adaptation by task demand may allow dynamic control of sensory-evoked signal flow in the neocortex.