In Experiment 3 of Moray's (1959) study on auditory attention, how was the independent variable operationalised?
Whether participants were instructed to focus on remembering digits or told they would be asked questions about the content of the shadowed message
Whether the instructions in the unattended channel were preceded by the participant's own name or a neutral prefix
The frequency and placement of digits within the shadowed message versus the rejected message
Whether participants were tested using a recognition task of words or a free-recall task of digits