Posts tagged neuroscience

Mo on Phineas Gage’s connectome

..neuroscientists from the University of California, Los Angeles have produced Gage’s connectome - a detailed wiring diagram of his brain, showing how its long-range connections were altered by the injury.

Using CT scans, MRI and DTI, researchers have come up with a model of Gage’s brain and the trajectory of the rod, showing what areas would have likely been damaged (interesting) but still leaving questions as to the extent/duration of the damage. I’ve heard a lot of mehs about the connectome project, and I know people that won’t even talk about it’s possible/potential usefulness, but I suppose that’s to be expected right out the gate. sigh.

Read Mo Costandi’s article here.

“Increased Frontotemporal Activation During Pain Observation in Sexual Sadism”

Sexual sadism is a psychiatric disorder in which sexual pleasure is derived from inflicting pain, suffering, or humiliation on others. While the psychological and forensic aspects of sexual sadism have been well characterized, little is known about the neurocognitive circuitry associated with the disorder. Sexual sadists show increased peripheral sexual arousal when observing other individuals in pain. The neural mechanisms underlying this unusual response are not well understood. We predicted that sadists relative to nonsadists would show increased responses in brain regions associated with sexual arousal (amygdala, hypothalamus, and ventral striatum) and affective pain processing (anterior cingulate and anterior insula) during pain observation. 

Sadists relative to nonsadists showed greater amygdala activation when viewing pain pictures. They also rated pain pictures higher on pain severity than nonsadists. Sadists but not nonsadists showed a positive correlation between pain severity ratings and activity in the anterior insula. [via]

The deal here is, sadists’ scans showed “unusually heightened” sensitivity to pain in others which ahhhh perfectly ties into my research hypothesis about the censored blankity blank levels in sadists compared to somethin’ somethin’ in the whosey whats. I’m still trying to push this proposal from being “accepted” to the green light stage where I can begin work.  I’m ready to be untied now, Sirs. 

Harenski, C., Thornton, D., Harenski, K., Decety, J., & Kiehl, K. (2012). Increased Frontotemporal Activation During Pain Observation in Sexual Sadism: Preliminary Findings Archives of General Psychiatry, 69 (3), 283-292 [img]

“Beyond Good and Evil: The Time-Course of Neural Activity Elicited by Specific Picture Content”

Event related potentials and negative bias: ERPs were time-locked to the stimulus onset, in this case, subjects were shown pictures sorted into the categories as shown in the figure above. Researchers measured the late positive potential or the LPP, which is understood to reflect motivated attention.

Overall, and as expected, unpleasant images elicited a larger response than neutral or pleasant images, specifically images of erotica and mutilation were compatible in LLPs, as were affiliative and threatening images - as you can see.  

No mention of mirror neuron activity, which would be interesting to look at.

[paper here]

“MIT researchers turn on a memory”

Researchers chose to test a simple kind of memory — a fear memory. In one experiment, mice were put in a chamber, allowed to explore, and given a foot shock. The next time the mice were put in the same dangerous chamber, they remembered the unpleasant electric shock and froze, taking on a defensive stance. Researchers had, however, inserted a gene that codes for a light-sensitive protein into the cells involved in making a memory. They then tested what happened when they turned on a light to activate those cells, without putting the mice in the same chamber. They saw the freezing behavior, as if the mice were reliving the memory.

“This is the most dramatic way to show that high cognitive phenomenon, like memory recall, can be generated, can be artificially generated by poking cells in the brain,” Tonegawa said in an interview.

He said there were about 20,000 neurons, or brain cells, involved in this particular kind of memory.  [via]

I’ve seen a couple of these optogenetic experiments. It’s pretty fascinating to be able to manipulate the neural response in vivo.  

It’s a simple but deeply unsettling question.

One that scientists are now starting to answer. …meet the scientist who believes he has found the moral molecule and the man who is using this new understanding to rewrite our ideas of crime and punishment.

The BBC’s (sensationalized) 4 part series here.

Memory is typically viewed as a process that is concerned with the past. One function of memory that has been largely overlooked until recently is its role in allowing individuals to imagine, envisage, or simulate possible future events.

However, a rapidly growing number of recent studies show that imagining possible future events depends on much of the same cognitive and neural machinery as does remembering past events.

The close linkage between remembering the past and imagining the future has potentially important implications for understanding the nature and function of memory…  

- Professor Daniel Schacter [via]

and there you are.

The ‘just going to leave this here, Product of the Day’: Shut-up Gun

• ‘Speech jamming gun’ that stops people talking by freezing the brain.

• The gadget fires a speaker’s words back to them causing them to stutter and then stop talking

• Delayed Auditory Feedback’ works because the brain does not like hearing the echo of the human voice [via]

 But it’s not all bad, seems counterintuitive… but delayed auditory feedback (DAF) has been shown to help people with speech impediments, like stuttering (depending on if it’s neurogenic or developmental).

Plus, these guys would appreciate it.

“I believe connectomes are the meeting ground for nature and nurture. The gene controls how the brain wires up, but experiences also modify the connections of the brain.”- MIT Neuroscientist, Sabastian Seung [via]

Most of you have heard of the Human Connectome Project. If not, have a look.

Using “state-of-the-art diffusion-imaging scanner” images of neural pathways are collected via a MRI looking machine, which allows scienctists to view connections of the brain “by tracking the passage of water molecules through nerve fibers, giving a more accurate picture of the brain’s structure and its neuronal pathways”. [via] Eventually, the idea is to identify connectopathies (abnormal circuits) then treat with appropriate pharmacology targeted for that area.

Above: [via] “White matter fiber architecture of the brain. Measured from diffusion spectral imaging (DSI). The fibers are color-coded by direction: red = left-right, green = anterior-posterior, blue = through brain stem. Martinos Center for Biomedical Imaging, Randy Buckner, PhD and the Laboratory of Neuro Imaging.”

Somehow the concept of making things happen and certain characteristics of resilience are intertwined for me. A short review of the literature suggests we are looking at the neural circuitry of fear and reward when talking about resilience. Of those areas, certain parts like the anterior cingulate cortex (ACC) overlap some areas I study in empathy erosion and notions of morality. This may seem counter intuitive, but as Feder et al. report in their paper Psychobiology and molecular genetics of resilience, ”greater capacity for emotion regulation has also been related to stress resilience”. Here’s more:

The functional capacity of the brain structures that are involved in the integrated circuits that mediate mood and emotion determines stress resilience, and is in turn reflected in an individual’s psychological make-up. More adaptive functioning of fear, reward, emotion regulation or social-behaviour circuits is thought to underlie a resilient individual’s capacity to face fears, experience positive emotions, search for positive ways to reframe stressful events and derive benefit from supportive friendships. Thus, resilience is an active process, not just the absence of pathology, and it can be promoted by enhancing protective factors. [via]

So when I’m thinking about the participants I may test (in this case: sadists), I’m also wondering about the other types of emotional regulation that share the same circuitry- maybe be something there, maybe not. I like to dig around. 

I’m told to get ready for some trouble with this study where I’m at now, but I’m still gonna try to make it happen. 

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Current status- Science of Evil: On Empathy and the Origins of Cruelty

by Simon Baron-Cohen

Empathy is a universal solvent.  

(…) 

And unlike the arms industry, which cost trillions of dollars to maintain, or the prison industry and legal system, which costs millions of dollars to keep oiled, empathy is free. And unlike religion, empathy cannot by definition oppress anyone.