Have you ever driven through a red light, unaware until your passengers start yelling at you? Have you ever been at a party, but somehow managed to still hear what your friend was saying in a room full of other conversations? Do you turn automatically when someone calls your name? All of this is thanks to the complex and confusing process called attention.
Even today, those involved in the study of attention and the mind are debating what exactly attention is--or, if it even exists at all. In 1890 and 1983, Harvard Psychologist William James wrote a seminal textbook called Principles of Psychology, where he gave one of the most commonly-cited definitions of attention yet. He defined it as when one out of many possible things is “taking possession [of] the mind”. But modern researchers claim that there are many forms of attention: selective attention, involuntary attention, multi-tasking attention, just to name a few!
Today we will look at selective attention. Selective attention is what we use when we’re at that party and want to listen to what our friend is saying rather than any (or all!) of the other conversations going on. We attend to our friend’s voice and ignore all of the other incoming voices. This is commonly referred to as the “cocktail party phenomenon”. Researchers originally looked into selective attention by having participants complete the “dichotic listening tasks”. Participants would be exposed to one verbal message in the left ear and a different verbal message in the right ear, at the same time. They were then required to answer questions about just one of these messages. Researchers found that if participants were told in advance which message they would get questions about, they could answer the questions easily. If they weren’t told which message to attend to in advance, they only got a few questions right, if any. Recent research into selective attention is examining whether we are better at attending to familiar voices, and whether selectively attending to speech that is “degraded” (i.e., difficult to understand) can improve our reception of it.
Which parts of the brain might be responsible for helping us selectively attend to things? For this answer, we will examine research that uses the Stroop Task. In the control condition of the Stroop Task, participants are given colour-words which are printed in their respective colour (so they will have the word “red” printed in red ink), and they are asked to name the colour of ink each word is printed in. In the experimental condition of the Stroop Task, participants are given a list of colour-words which are printed in colours other than the ones they name. For example, one of these words might be “red”, but it is printed in blue ink. Again, they must go through the list and name what colour of ink each word is printed in. So, they must selectively attend to the colour while ignoring the word itself. Most people find the urge to read the word very strong and therefore very distracting in this task; they describe feeling like they must actively ignore the written word in order to succeed in naming the ink colour. This helps us to demonstrate the concept of controlled versus automatic processing. There are some things that our brain processes pretty much automatically or subconsciously, without us paying much attention to it. Reading is generally considered one of these processes; we don’t have to put active effort into reading. Most of us, when confronted with text, will automatically begin reading/processing it. Other things require our full attention and effort in order to process them. Actually understanding what you have read is often considered a controlled process--you must think about the meanings of the words and compare the message with previous knowledge. Have you ever found yourself reading something, only to get to the end of the page and realize you don’t remember what you just read? This is an example of switching from controlled to automatic processing.
There have been many neuroimaging studies done on participants attempting the Stroop Task. These studies assess blood flow to different areas of the brain during the control condition and compare those results to ones gathered from the experimental condition. Two key areas have been identified in this task: the dorsolateral prefrontal cortex (DLPFC) and the anterior cingulate cortex (ACC). Both of these areas are thought to play a role in helping the brain to select important information to attend to, while actively suppressing (ignoring) unimportant information. The ACC is speculated to be particularly responsible for detecting conflicting response urges, such as the ones found in the Stroop Task.
If someone calls your name, do you turn to them right away, or do you spend time considering whether you want to speak with this person before turning? If you aren’t expecting them to call your name, you will turn to them automatically. This is a primary example of something called attention capture, which is when something is so powerful or important that it forces us to pay immediate attention to it, even when our attention was just focused on something else. Researchers suspect this evolved as an instinct to help us quickly notice both threats and opportunities in the environment (e.g., prey). Focused attention can cause many problems, though… The reverse of attention capture is something called inattentional blindness. Inattentional blindness is the failure to pay attention to something that might be important or otherwise expected for us to notice. For example, a pilot carefully paying attention to his display console may completely fail to notice another airplane blocking the runway. In an experiment by Daniel Simons, participants were shown videos of teams playing basketball and were asked to count the number of passes that one of the teams made. Mid-video, a person in a gorilla costume walked across the screen. Participants weren’t told about this gorilla beforehand, and while most participants could accurately tell you how many passes the team made, 73% of participants didn’t notice the gorilla! In another version of this task, the gorilla paused in the middle of the court and pounded on his chest, but 50% of participants still didn’t notice it!
So, next time someone teases you about walking into something while you’re texting, I hope you tell them about selective attention and inattentional blindness!
Reference: Cognition, 5th Edition. Smilek, Sinnet, & Kingstone. Oxford University Press, 2013.