Are evolutionarily threatening animals attentionally prioritized under restricted visual awareness? : Two visual probing experiments
Parantainen, Atte (2019-03-21)
The present study investigated whether the perception of evolutionarily threatening animals is prioritized under restricted awareness. The study examined whether snake and spider pictures have attentional priority when compared to bird and frog pictures. Snake and spider pictures were expected to have attentional priority because of their long history as evolutionarily dangerous animals. Prior research has focused especially on the prioritization of snakes in perception (snake detection hypothesis). Two experiments were conducted: a masked visual probing experiment (Experiment 1, n = 40) with 12 ms display time of the animal pictures, and another experiment without the masking procedure (Experiment 2, n = 42) which used the same 12 ms display time. Both forward and backward masking were used in Experiment 1. Reaction time and response accuracy were recorded in the dot probe tasks of both experiments. Experiment 1 also included an awareness task, which was used to assess whether the masking procedure was effective and the perception of the animals remained subliminal. Both objective (discrimination accuracy) and subjective (self-reported awareness) measures were used to evaluate the participants’ awareness of the animal pictures. Signal detection theory was applied in assessing the discrimination accuracy ratings by transforming the accuracy ratings into d’ values. No spatial prioritization of attention related to snakes or spiders was found as indicated by the reaction times in the dot probe tasks. This means that the initial hypothesis was not confirmed. The response accuracies demonstrated no clear or consistent effects related to snakes or spiders. Concerning the awareness task results, both detection accuracy and self-reported awareness demonstrated slightly above chance-level discrimination of animal-present trials from no-animal trials. These results suggest that the masking procedure did not entirely block awareness of the animal pictures. In the awareness task, snake stimuli produced more efficient detection than spider stimuli according to both objective and subjective measures. Despite no findings from the dot probe tasks, the results from the awareness task provide some evidence for the snake detection hypothesis.