Periodic Reporting for period 1 - PtoACons (Going from Phenomenal to Access Consciousness: Neurobehavioural correlates of visual consciousness development and its underlying cognitive procesess.)
Période du rapport: 2016-10-01 au 2018-09-30
The route from P- to A- consciousness involves several cognitive processes, such as attention, memory, decision-making and metacognition, which are intermingled and spatiotemporally overlaped.
Due to this complex overlap, the study of visual consciousness needs to be carried out in a comprehensive framework. Therefore, the present project pursues two general aims: 1) To dissociate the behavioural responses and neurofunctional correlates of P- and A- consciousness, distinguishing between objective and subjective measures. 2) To elucidate how the cognitive processes of attention, (iconic and working) memory and their interactions are involved in the development of the conscious content. Better understanding of the neural basis of attention, visual consciousness, and metacognition may aid in developing solutions for societal problems by, for example, implementing new devices of road safety and programs of interventions aimed at improving academic success."
At this aim, we used a change-detection paradigm (see Figure 2) in which participants had to indicate whether a probed item (a letter) was the same or different to the item shown at that corresponding location in the memory array. Afterwards, participants were asked to rate their confidence about their response. The cue-probe indicating the location of the probed item was presented at different latencies to test different stages of information processing (iconic, fragile visual short-term and visual working memory; see Vandenbroucke et al.2011).
Two types of measures have been collected in each memory condition: 1) sensitivity measures (d’) as objective measures and 2) mean confidence ratings as subjective measures.
Attention before the memory array presentation was manipulated in three different ways: by asking participants to voluntary direct their spatial attention to a specific location; by automatically attracting participant’s spatial attention to a specific location by the presentation of a salient stimulus; and by asking participants to perform the change detection task alone (no load condition) or while trying to simultaneously carrying out a calculation problem (high load condition; double task).
Results.
When attention was voluntarily directed, the impact of attention on sensitivity changed depending on the memory condition, with larger attentional modulations at later stages (working memory) than at earlier stages (iconic memory) of information storage. When participants voluntarily direct their attention, they were able to accurately judge their performance.
When attention was automatically captured by a salient stimulus, attentional modulations on sensitivity were the same independently of the memory condition. Interestingly, the effect of attention on confidence ratings depended on the condition of memory. Despite sensitivity at attended locations was significantly higher for iconic memory than for working memory, participants were not aware about it.
The reduction of attentional control due to the engagement in a double-task, produced a decrease of sensitivity, which was independent of the memory condition. Interestingly confidence ratings were not modulated by the attentional load: even though participants’ sensitivity was higher in the no-load than in the high-load condition, their confidence in their response was the same, suggesting that they were not conscious about the reduction of their memory performance.
Moreover, we observed that different ways of directing our spatial attention can give place to different outputs in metacognition. In particular, our results suggest that when we attend to a specific location in a voluntary fashion, we are more precise in judging our own memory performance. Contrariwise, attention automatically captured by salient stimuli can lead to metacognition errors leading us to erroneously believe that we remember more than we are effectively able to remember. This last result, which will need to be replicated in future studies, could be particularly interesting for developing new educational training programs in which the use of voluntary attentional strategies is promoted as a means to improve metacognitive skills.