via NeuroLogica Blog
First, take the challenge presented in this video:
This is a demonstration of inattentional blindness (or attentional blindness) – when we are focused on one task this interferes with our processing of other information. This is exactly why you should not text while driving, or even talk on the phone while driving.
The cause of this is conceptually simple: our brains have limited processing power, more limited than we would like to think. When we use some of that processing power for one task it is not available for other tasks, even basic tasks like seeing obvious things right in front of our eyes. This concept is called load theory, and researchers have documented numerous ways in which it manifests. A related concept is that of interference – when we perform one task it reduces our performance on other tasks. In fact, the act of multitasking itself causes interference because multitasking requires processing power (it takes brain power to switch among more than one task) which is taken away from each task.
Interference is probably greater for tasks that are vying for the same parts of the brain. It seems that different areas or modules in the brain participate in multiple networks engaging in different tasks. Placing a processing load on one module for different tasks causes significant interference. Some modules participate is very basic functions, like perception, attention, and memory, and therefore become overloaded very easily.
A recent study has demonstrated a new aspect of this phenomenon. Up to now research demonstrating inattentional blindness has used visual clutter to distract from seeing the target – following the basketball interfered with the ability to detect the gorilla. The new research creates the same effect without visual clutter but instead using visual memory:
Participants in the study were given a visual memory task to complete while the researchers looked at the activity in their brains using functional magnetic resonance imaging. The findings revealed that while the participants were occupied with remembering an image they had just been shown, they failed to notice a flash of light that they were asked to detect, even though there was nothing else in their visual field at the time.
This research suggests that remembering an image uses similar resources to seeing an image – that visual memory and perception are similar in terms of the brain resources that are used (which is in line with previous research).
Assuming the results of this study are reproducible, it extends the implications of inattentional blindness. Not only is texting or using a cell phone distracting while driving, the researchers suggest that trying to visualize directions or remember that image on a navigational GPS system can cause interference and reduce a driver’s ability to detect obstacles in front of them.
There are a few take-home messages from this line of research I would like to emphasize.
MORE . . .
Related articles
- More Inattentional Blindness (theness.com)
- Study reveals how memory load leaves us ‘blind’ to new visual information (eurekalert.org)
- Inattentional Blindness: How Memory Load Leaves Us ‘Blind’ To New Visual Information (medicalnewstoday.com)

Inattentional blindness is an inability to perceive something that is within one’s direct perceptual field because one is attending to something else. The term was coined by psychologists Arien Mack and Irvin Rock, who identified the phenomenon while studying the relationship of attention to perception. They were able to show that, under a number of different conditions, if subjects were not attending to a visual stimulus but were attending to something else in the visual field, a significant percentage of the subjects were “blind” to something that was right before their eyes.