There are at least three points where we seem to get stuck, says Marois. The first is simply identifying what we’re looking at. This can take a few tenths of a second during which crucial window of concentration we are incapable of seeing and recognising a second item. This limitation is known as the attentional blink. A second limitation is our short-term visual memory. This capacity shortage is thought to explain, in part, our astonishing inability to detect even huge changes in scenes that are otherwise identical, so-called change blindness. A third limitation is that choosing a response to one stimulus will hold back by some tenths of a second your ability to respond to a parallel one. This is called the response selection bottleneck theory, first proposed in 1952 and elaborated on by Marois and his colleagues in 2006.
Meyer argues that individual differences come down to variations in the character of the processor—some brains are just more ‘cautious’, some more ‘daring’. And contrary to popular belief, there are no noticeable differences between men and women. Meyer believes that it’s not a central bottleneck which causes dual-task ‘interference’ but rather adaptive executive control which ‘schedules task processes appropriately to obey instructions about their relative priorities and serial order’.
Questions
1. The phrase ‘attentional blink’ describes
2. Scientists talk about ‘change blindness’ to denote
3. The idea of the ‘response selection bottleneck’ was suggested as an explanation for
4. Meyer uses the term ‘adaptive executive control’ to refer to