"WHAT'S THAT BEHIND YOU???"

Fear and Attention

by Isabel Acosta, 2007-49035

EEEEEK!!! Admit it, you jumped off your seat and yelped like a little girl when you saw that picture amidst the sea of text. While scanning through this blog, I'm sure this little monster grabbed your attention almost instantly, and I'm pretty sure you hate me for posting it too

(especially if you are reading this at night). I apologize for your maybe subsequent nightmare, but you just helped me prove my point --fear catches our attention, and it catches it pretty intensely.

In movies, someone always points out a dangerous animal, ghost, a monster, or an incoming axe murderer amidst a scene. These dangerous stimuli are picked up so quickly, and they are hardly ever missed. Öhman, Flykt, & Esteves (2001) sought to find out if fear-relevant stimuli are detected faster than fear-irrelevant stimuli. The team conducted three experiments to test whether there is a difference in reaction time between the two kinds of stimuli.

In Experiment 1, the team wanted to find out if it would be faster to detect a fear-relevant target amidst a background of fear-irrelevant stimuli, or if it was the other way around. They created a 3x3 matrix consisting of nine pictures. The fear-relevant pictures were of snakes or spiders, while the fear-irrelevant pictures were of mushrooms and flowers. The team chose snakes and spiders, because of the literature that suggest that these stimuli are potential survival threats. The grids were projected to a screen. The participants had to press a switch on their left hand if all nine pictures in the matrix came from one category (like, all flowers, all snakes, all mushrooms etcetera), and they had to press on the microswitch on their right hand (preferred hand) if there was a different stimulus in the matrix. The responses made on these microswitches were measured to the nearest millisecond.

I'm scared of cats, so yup, I spotted this one a mile away.

The results of this experiment showed that fear-relevant stimuli were detected faster then fear-irrelevant stimuli. Also, location had no effect on how fast the snakes or spiders were detected, but it had an effect on the latency of detecting flowers or mushrooms. Fear-irrelevant stimuli were best detected if they were located in the middle, or near the fixation point. Fear-relevant stimuli prompted rapid shifts of attention from one picture to another, since location had no effect on the reaction time of the participant. This suggests that fear-relevant targets go through automatic and preattentive detection, despite spatial location. They just "pop out," wherever they may be.

The team felt the need to vary the number of distractor stimuli (the background), in order to test the search efficiency. In Experiment 2, the team presented 3x3 matrices along with 2x2 matrices of the same pictures. The same procedure was followed (the two microswitches). Results showed fear-relevant stimuli were still detected faster than fear-irrelevant stimuli, regardless of the number of distractors. Also, matrix size/number of distractors had no effect on the latency of detecting fear-relevant stimuli --the reaction time for detecting snakes and spiders in a 3x3 matrix and 2x2 matrix were the same. Errors were also less made when detecting fear-relevant targets. The team also found that it was also faster to detect if a target was not present in a fear-relevant background. This suggests that processing fear-relevant material is more efficient. Participants were faster in shifting their attention to fear-relevant targets (shorter time to detect snake or spider in background of flowers or mushrooms) AND they were faster in disengaging attention from fear-relevant stimuli (shorter time to decide if target was not present in a background of snakes or spiders). Experiments 1 and 2 suggest that humans must have an attention control setting to automatically attend to stimuli implying some degree of threat.

Did you spot the snake?

The team wanted to find out though if emotional intensity had any effect on attention/detection. What if the sample consisted of people who were truly afraid of snakes or spiders, would their reaction time to these stimuli be different? In Experiment 3, participants were asked to answer true or false items about their fear of snakes or spiders. Participants must be fearful of either snakes or spiders, but not both. Participants garnering high scores on either snakes or spiders (8-9 points) and obtaining below the median scores for the other stimuli were selected, forming high-fear groups. This group's performance was compared to the performance of a control group, who scored below the median for both stimuli. The results proved to be consistent, there was still faster detection of fear-relevant stimuli in both groups (no overall difference in reaction time), but fearful participants detected their feared stimulus even faster than their non-feared fear-relevant stimulus. They were then faster in detecting their feared stimulus than the controls. Also, it was interesting to find out that fearful participants made more errors than the control group only when asked to identify fear-irrelevant targets. This means that the fear-relevant distractors, well, distracted them from detecting the targets. There is an evident sensitivity to the things we fear! Attentional bias exists!

When you enter a room, and you are afraid of spiders, you are probably the first one to spot one in the room. This spider is an exception, of course.

If you're too lazy to read the paragraphs above, the researchers summarized their findings in six main points:

1) Participants were consistently faster to find a fear-relevant stimulus (snake or spider) than a fear-irrelevant stimulus (flower or mushroom) against backgrounds of fear-irrelevant and fear-relevent stimulim respectively.

2) Location in the matrix did not affect the latency of finding a fear-relevant target stimulus (can prompt shifts in attention). But it had an effect on fear-irrelevant stimulus.

3) Latency of finding fear-relevant targets was not significantly increased when the number of distractors was increased from three to eight (2x2 vs 3x3).

4) It was faster to decide that no target was present in a fear-relevant matrix than in fear-irrelevant matrix.

5) Error rates were low in small matrices, and participates were more accurate in locating fear-relevant than fear-irrelevant targets.

6) Bias for discovering threatening stimuli faster than nonthreatening ones was enhanced in participants specifically fearful of the target. But fearful participants were generally less accurate when tasked to decide whether a target was present among fear-relevant distractors. Thus, fear produced by the distractors interfered with target detection.

I find this experiment so interesting! Threat potential is an important factor in quickly capturing attention, which has evolutionary significance. The researchers tried to explain this. Apparently, when we scan a scene for threatening stimuli, we rely on passive and stimulus-driven attention. When we scan a scene for food, we rely on active and goal-driven attention. So, in order to detect threats that we are not specifically focused on (like threats on the periphery), humans must have the capability to automatically scan and analyze the perceptual field preattentively. Preattentive visual attention is fast, automatic and works on low-level stimulus features, while Postattentive visual attention is slow, deliberate and is concerned with complex inferential and interpretative processes. When peripheral threats or other significant stimuli are experienced by surprise, they interrupt our current processing and are prioritized for further sensory and interpretative processing. These stimuli are prioritized according to the current goals of the individual --the likelihood of stimuli to capture attention is in accordance with their relevance for the current goals of the individual. Humanity's main goal is survival; therefore, survival threats were probably selected by the environment to be automatic triggers of attention. There is a general bias to preferentially direct attention toward evolutionary fear-relevant stimuli among humans.

Spot anyone different? If not, something's definitely wrong with your conception of scary and threatening.

This concept is applicable to perceiving angry or threatening faces in a crowd. Hansen and Hansen (1988) found out that participants easily detected a threatening angry face amidst a background of happy faces, a phenomenon they called "anger superiority effect." Any form of evolutionary significant stimuli can be automatically detected in a scene. In a previous study of Esteves, et. al. (1994), he and his team found out that angry faces can activate psychophysiological responses even though they were masked by neutral faces. These studies, along with the study I just wrote about, suggest evidence that there is a coupling of automatic emotional response activation and efficient capture of attention. This suggests that emotion probably involves "attention control settings" that make goal-relevant stimuli salient for the person (which make them automatically capture attention). What captures our attention is therefore dependent on our current emotional or motivational states. Isn't this just so interesting? Since this study concentrated mainly on fear and threats, I plan to read more into the motivational influences on visual perception, so stay tuned for that one.

What scares us, captures us. "Haunting" is now such an appropriate word to describe the things we fear. Our fears guide the things we watch our for and attend to in the environment. It is such an intelligent way of processing the environment, don't you think? It certainly ensures our survival and the persistence of our species' existence. It is really amazing how the things we see and notice is biased, and that this bias actually favors the continuation of our human generation. I really do not know how God thought of all of this, but wow, that is one amazing plan.

See, now being a coward isn't so bad. You're merely watching out for yourself, and for the future members of your lineage right? ;)

Works Cited:

Öhman, A., Flykt, A., & Esteves, F. (2001). Emotion Drives Attention: Detecting the Snake in the Grass. Journal of Experimental Psychology , 130 (3), 466-478.

Esteves, P., Dimberg, U., & Ohman, A. (1994). Automatically elicited fear: Conditioned skin conductance responses to masked facial expressions. Cognition and Emotion, 8, 393-413.

Hansen, C. H., & Hansen, R. D. (1988). Finding the face in the crowd: An anger superiority effect. Journal of Personality and Social Psychology, 54, 917-924.