Neuroscience
Forget snakes on a plane, this was snakes in a brain scanner! To chart the neural activity associated with overcoming fear, Uri Nili and colleagues scanned snake-phobic participants' brains while they chose, with the press of a button, whether or not to bring a live, 1.5M long corn snake, located on a conveyer belt in the scanner room, nearer to their heads, or to shift it further away (watch video). A control condition replaced the snake with a teddy bear.
The subgenual anterior cingulate cortex (sgACC) - part of the frontal cortex buried under the corpus callosum - emerged as a key area involved when participants chose to overcome their fear and bring the snake closer to their heads - i.e. when they acted courageously. When people reported high fear but chose to bring the snake closer, sgACC activity increased, whilst physiological markers of fear dropped and activity in emotion processing regions, such as the amygdala, was reduced. Nili's team said this suggests the sgACC plays a role in dampening down fear-related bodily arousal. Consistent with this, the sgACC is known to be involved in regulating the paraysmpathetic nervous system (which is in opposition to the fight or flight response) and is deeply interconnected with brain structures involved in emotional processing.
In contrast, when courage failed and the participants chose to direct the snake further from them, sgACC activity dropped away (no longer correlating with fear levels), somatic signs of fear increased, as did activity in emotion-processing regions like the amygdala.
The only other brain region that was more active during displays of courage was the right temporal pole - a part of the brain that's known to be involved in modulating emotions triggered by visual stimuli, and also in the self-evaluation and monitoring of one's own emotions.
This new research has some important and exciting implications. From a practical perspective, the fact that bodily signs of fear were reduced during moments of courage, even while subjective fear was high, raises a concern with studies that use physiological measures (such as sweatiness of the skin) as a marker for fear. For example, studies of therapeutic interventions for phobias, which rely on physiological markers, risk mistaking what's in fact a display of courage for successful fear eradication.
Manipulating sgACC activity could also be a new target for therapy: 'Such interventions may range from training in meditation techniques that lead to greater activity in this region,' the researchers said, 'to transcranial magnetic stimulation similar to that attempted to alleviate depression.'
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Nili, U., Goldberg, H., Weizman, A., & Dudai, Y. (2010). Fear Thou Not: Activity of Frontal and Temporal Circuits in Moments of Real-Life Courage. Neuron, 66 (6), 949-962 DOI: 10.1016/j.neuron.2010.06.009
Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.
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Neuroscience
Snakes in a brain scanner!
The subgenual anterior cingulate cortex (sgACC) - part of the frontal cortex buried under the corpus callosum - emerged as a key area involved when participants chose to overcome their fear and bring the snake closer to their heads - i.e. when they acted courageously. When people reported high fear but chose to bring the snake closer, sgACC activity increased, whilst physiological markers of fear dropped and activity in emotion processing regions, such as the amygdala, was reduced. Nili's team said this suggests the sgACC plays a role in dampening down fear-related bodily arousal. Consistent with this, the sgACC is known to be involved in regulating the paraysmpathetic nervous system (which is in opposition to the fight or flight response) and is deeply interconnected with brain structures involved in emotional processing.
In contrast, when courage failed and the participants chose to direct the snake further from them, sgACC activity dropped away (no longer correlating with fear levels), somatic signs of fear increased, as did activity in emotion-processing regions like the amygdala.
The only other brain region that was more active during displays of courage was the right temporal pole - a part of the brain that's known to be involved in modulating emotions triggered by visual stimuli, and also in the self-evaluation and monitoring of one's own emotions.
This new research has some important and exciting implications. From a practical perspective, the fact that bodily signs of fear were reduced during moments of courage, even while subjective fear was high, raises a concern with studies that use physiological measures (such as sweatiness of the skin) as a marker for fear. For example, studies of therapeutic interventions for phobias, which rely on physiological markers, risk mistaking what's in fact a display of courage for successful fear eradication.
Manipulating sgACC activity could also be a new target for therapy: 'Such interventions may range from training in meditation techniques that lead to greater activity in this region,' the researchers said, 'to transcranial magnetic stimulation similar to that attempted to alleviate depression.'
_________________________________
Nili, U., Goldberg, H., Weizman, A., & Dudai, Y. (2010). Fear Thou Not: Activity of Frontal and Temporal Circuits in Moments of Real-Life Courage. Neuron, 66 (6), 949-962 DOI: 10.1016/j.neuron.2010.06.009Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.
- More Evidence That Fear Of Snakes Is Hard-wired
Slithery, scaly, and downright terrifying is how many people view snakes. Even in Britain, which has only one species of poisonous snake, people are often afraid. Some experts have suggested the snake's public relations problem is based on the fact...
- Brain Dread
It makes time slow down when you want it to go fast, and it keeps turning your mind back to the very thing you want to forget – dread is a most unpleasant emotion. Now Gregory Berns (pictured) and colleagues at Emory University School of Medicine think...
- A Social 'viagra' For Shy People?
The days of finding Dutch courage in a quick drink before a stressful situation could soon be over – researchers have reported that a few sniffs of the hormone oxytocin can dampen the brain’s fear response to threatening images. The finding follows...
- Learned Fear Of People Who Are Different
Some people are predisposed to fearing those whose skin colour is different from their own, in much the same way they are predisposed to fearing snakes and spiders. Andreas Olsson and colleagues presented participants with two photos, one of a black male...
- Abnormal Social Cognition
To investigate the neuroscience behind socialising, Andreas Meyer-Lindenberg and colleagues have scanned the brains of people with the genetic disorder Williams-Beuren syndrome and compared them with scans of healthy controls. People with Williams syndrome...