Daryle Lockhart
This is my personal blog, filled with wondrous things from across the Universe, which will hopefully inspire you to go change the world, or at least, your seat.


Notes on Neurobiological Substrates of Punishment

  •  Impulsive punishment may relate to amygdala-based circuitry (AM/PAG, yellow), where there is associative learning between cues and outcomes.
  • Instrumental punishment may be connected to striatal-mediated reinforcement for goal oriented actions. This type of punishment may lead to appetitive retributive goals (fascinating), possibly coming from the MFOC (medial orbitofrontal cortex), or from forward-planning areas of the prefrontal cortex which also plays a role in theory of mind (blue areas).
  • These appetitive/instinctual actions may reinforce further action through the dorsomedial striatum (DMS,green) which if becoming “habit-based”, we’re then looking at reinforced action through dorsolateral striatum (DLS, red), which would likely indicate dopamine-dependent circuits. 

[via: The Neurobiology of Punishment]


Is Neuroscience the Death of Free Will?

This is one of the most prominent debates in neuroscience and behavior going on today. As we are learning more and more about unconscious behaviors and attitudes, the notion of free will and personal choice, and especially the implications on the criminal justice system, are taking center stage. This is a great article to read if you are new to the topic or just want to see some current debate on the matter. Here are some of the highlights, although I highly recommend reading the entire article (it isn’t that long). Keep in mind that the author is in the camp of free will, and there are definitely more sides to the story.

Daniel Wegner: “It seems we are agents. It seems we cause what we do… It is sobering and ultimately accurate to call all this an illusion.”

Neuroscientist Patrick Haggard declared, “We certainly don’t have free will.  Not in the sense we think.”  

Neuroscientist Sam Harris claimed, “You seem to be an agent acting of your own free will. The problem, however, is that this point of view cannot be reconciled with what we know about the human brain.”

The sciences of the mind do give us good reasons to think that our minds are made of matter.  But to conclude that consciousness or free will is thereby an illusion is too quick.

These capacities for conscious deliberation, rational thinking and self-control are not magical abilities.  They need not belong to immaterial souls outside the realm of scientific understanding (indeed, since we don’t know how souls are supposed to work, souls would not help to explain these capacities).  Rather, these are the sorts of cognitive capacities that psychologists and neuroscientists are well positioned to study.

So, does neuroscience mean the death of free will?  Well, it could if it somehow demonstrated that conscious deliberation and rational self-control did not really exist or that they worked in a sheltered corner of the brain that has no influence on our actions.  But neither of these possibilities is likely.  True, the mind sciences will continue to show that consciousness does not work in just the ways we thought, and they already suggest significant limitations on the extent of our rationality, self-knowledge, and self-control.  Such discoveries suggest that most of us possess less free will than we tend to think, and they may inform debates about our degrees of responsibility.  But they do not show that free will is an illusion.

I actually do not agree with this guy. I do think that free will is an illusion for the most part. I am not ready to fully dismiss free will yet, but I do think it exists in a very limited capacity. 

Any thoughts on this matter?


Psychologists Decipher Brain’s Clever Autofocus Software

It’s something we all take for granted: our ability to look at an object, near or far, and bring it instantly into focus. The eyes of humans and many animals do this almost instantaneously and with stunning accuracy. Now researchers say they are one step closer to understanding how the brain accomplishes this feat.

In an attempt to resolve the question of how humans and animals might use blur to accurately estimate distance, Geisler and Burge used well-known mathematical equations to create a computer simulation of the human visual system. They presented the computer with digital images of natural scenes similar to what a person might see, such as faces, flowers, or scenery, and observed that although the content of these images varied widely, many features of the images—patterns of sharpness and blurriness and relative amounts of detail—remained the same.

The duo then attempted to mimic how the human visual system might be processing these images by adding a set of filters to their model designed to detect these features. When they blurred the images by systematically changing the focus error in the computer simulation and tested the response of the filters, the researchers found that they could predict the exact amount of focus error by the pattern of response they observed in the feature detectors. The researchers say this provides a potential explanation for how the brains of humans and animals can quickly and accurately determine focus error without guessing and checking. Their research appears online this week in the Proceedings of the National Academy of Sciences.

Read full article

(via afro-dominicano)


Diabetic Rats Cured With Their Own Stem Cells

A cure for diabetes could be sitting in our brains. Neural stem cells, extracted from rats via the nose, have been turned into pancreatic cells that can manufacture insulin to treat diabetes.

Beta cells in the pancreas produce insulin, which regulates glucose levels. People with diabetes either have type 1, in which native beta cells are destroyed by the immune system, or type 2, in which beta cells cannot produce enough insulin.

To replace lost or malfunctioning beta cells, Tomoko Kuwabara of the National Institute of Advanced Industrial Science and Technology in Tsukuba Science City, Japan, and colleagues turned to neural stem cells in the brain.

(via afro-dominicano)


A brief history of the brain

An amazing feature in New Scientist explores how brains came into being, from the days of single-celled organisms and chemical signals to the modern human brain and its capacity for abstract artistic thought. Don’t miss this one.

How did we acquire our beautiful brains? How did the savage struggle for survival produce such an extraordinary object? This is a difficult question to answer, not least because brains do not fossilise. Thanks to the latest technologies, though, we can now trace the brain’s evolution in unprecedented detail, from a time before the very first nerve cells right up to the age of cave art and cubism.

(via New Scientist, image via foxtongue on Flickr)

(via jtotheizzoe)


A Brief History of The Brain

I’ve always been fascinated with how interconnections form and aid different species. But what fascinates me even more is how humans tend to ignore this one detail of nature that shows teamwork does in fact help a species adapt, survive and evolve. From fungi and plants teaming to create a healthy network out of a resource based economy to the neural cell network in our developing brains. Take a few notes from nature and the human race just might survive for a little longer. Below is an excerpt from an NS article I was reading about the human brain’s biological history. And while the article itself gives more highlights to the evolution of the brain, the bit of how the brain acquired the ability to communicate seemed very interesting to myself.

The evolution of multicellular animals depended on cells being able to sense and respond to other cells - to work together. Sponges, for example, filter food from the water they pump through the channels in their bodies. They can slowly inflate and constrict these channels to expel any sediment and prevent them clogging up. These movements are triggered when cells detect chemical messengers like glutamate or GABA, pumped out by other cells in the sponge. These chemicals play a similar role in our brains today (Journal of Experimental Biology, vol 213, p 2310).

Recent studies have shown that many of the components needed to transmit electrical signals, and to release and detect chemical signals, are found in single-celled organisms known as choanoflagellates. That is significant because ancient choanoflagellates are thought to have given rise to animals around 850 million years ago.

So almost from the start, the cells within early animals had the potential to communicate with each other using electrical pulses and chemical signals. From there, it was not a big leap for some cells to become specialised for carrying messages.

These nerve cells evolved long, wire-like extensions - axons - for carrying electrical signals over long distances. They still pass signals on to other cells by releasing chemicals such as glutamate, but they do so where they meet them, at synapses. That means the chemicals only have to diffuse across a tiny gap, greatly speeding things up. And so, very early on, the nervous system was born.

Read full article for an In-depth look on the brain’s beginning

(via afro-dominicano)


 Scientists ‘See’ YouTube Videos in the Mind

What if what you saw with your eyes could be interpreted in a brain-scanner? Well, that just happened. Check it out:

Gallant’s coauthors acted as study subjects, watching YouTube videos inside a magnetic resonance imaging machine for several hours at a time. The team then used the brain imaging data to develop a computer model that matched features of the videos — like colors, shapes and movements — with patterns of brain activity.

“Once we had this model built, we could read brain activity for that subject and run it backwards through the model to try to uncover what the viewer saw,” said Gallant.

Subtle changes in blood flow to visual areas of the brain, measured by functional MRI, predicted what was on the screen at the time — whether it was Steve Martin as Inspector Clouseau or an airplane. The reconstructed videos are blurry because they layer all the YouTube clips that matched the subject’s brain activity pattern. The result is a haunting, almost dream-like version of the video as seen by the mind’s eye.

(via  ABC News)

(via jtotheizzoe)

Can Computers Reconstruct Your Dreams?


I’ve never cared much for dream interpretation.  Most of our remembered dreams have always seemed like our minds filling gaps in dreams with our previous experiences and perceptions.  Sorry to the psychoanalytic/psychodynamic people out there, but I never bought into it.  

This is actually pretty amazing.  Scientists have begun to reconstruct images from dreams and hallucinations.

It sounds like science fiction: While volunteers watched movie clips, a scanner watched their brains. And from their brain activity, a computer made rough reconstructions of what they viewed.

The reconstructions are blends of the YouTube snippets, which makes them blurry. Some are better than others. If a human appeared in the original clip, a human form generally showed up in the reconstruction. But one clip that showed elephants walking left to right led to a reconstruction that looked like “a shambling mound,” Gallant said. The YouTube clips hadn’t shown elephants and so “we just had to make do with what we had.”

The quality could be improved by better techniques to blend human forms, as well as a bigger storehouse of moving images, he said.

Still, the overall results are “one of the most impressive demonstrations of the scientific knowledge of how the visual system works,” said Marcel Just, director of the Center for Cognitive Brain Imaging at Carnegie Mellon University.

 Think about the possibilities.  How much would you pay to have your dreams reconstructed?  What about visual representations of schizophrenic hallucinations?  Could we apply this technology to coma patients and see what they are experiencing?  This is a peek inside the human mind AND the human visual system. 

Absolutely fascinating.


Cooling The Active Brain by Yawning

More Than a Sign of Sleepiness, Yawning May Cool the Brain: Though considered a mark of boredom or fatigue, yawning might also be a trait of the hot-headed. Literally.

A study led by Andrew Gallup, a postdoctoral research associate in Princeton University’s Department of Ecology and Evolutionary Biology, is the first involving humans to show that yawning frequency varies with the season and that people are less likely to yawn when the heat outdoors exceeds body temperature. Gallup and his co-author Omar Eldakar, a postdoctoral fellow in the University of Arizona’s Center for Insect Science, report this month in the journal Frontiers in Evolutionary Neuroscience that this seasonal disparity indicates that yawning could serve as a method for regulating brain temperature.

Gallup and Eldakar documented the yawning frequency of 160 people in the winter and summer in Tucson, Arizona, with 80 people for each season. They found that participants were more likely to yawn in the winter, as opposed to the summer when ambient temperatures were equal to or exceeding body temperature. The researchers concluded that warmer temperatures provide no relief for overheated brains, which, according to the thermoregulatory theory of yawning, stay cool via a heat exchange with the air drawn in during a yawn.

Full Article

The science of why laughing makes you happier


Laughter is regularly promoted as a source of health and well being, but it has been hard to pin down exactly why laughing until it hurts feels so good.  

The answer, reports Robin Dunbar, an evolutionary psychologist at Oxford, is not the intellectual pleasure of cerebral humor, but the physical act of laughing. The simple muscular exertions involved in producing the familiar ha, ha, ha, he said, trigger an increase in endorphins, the brain chemicals known for their feel-good effect.

… Social laughter, Dr. Dunbar suggests, relaxed and contagious, is “grooming at a distance,” an activity that fosters closeness in a group the way one-on-one grooming, patting and delousing promote and maintain bonds between individual primates of all sorts.


Why some seconds seem to last forever

Though our perception of time can be stunningly precise — given a beat to keep, professional drummers are accurate within milliseconds — it can also be curiously plastic. Some moments seem to last longer than others, and scientists don’t know why.

Unlike our other senses, our perception of time has no defined location in our brain, making it difficult to understand and study. But now researchers have found hints that our sense of time stems from specialized units in our brain, channels of neurons tuned to signals of certain time lengths.

“We know keeping track of time is incredibly important, it allows us to coordinate movements, interpret body language,” said optometrist James Heron of the University of Bradford in the UK, lead author of the study in Proceedings of the Royal Society B, Aug. 10. “We know the brain does this routinely and accurately, but we’re not sure how. Our evidence strongly suggests the presence of neural units in the brain that are tuned to different durations.”

Death in dolphins: do they understand they are mortal? | New Scientist

REPORTS of dolphins interacting with dead members of their pod are raising questions about whether cetaceans understand the concept of death. Bottlenose dolphins in western Greece have been seen reacting to death differently depending on whether a pod member has died suddenly or after a longer period of illness, New Scientist has learned.

Interpreting animal behaviour after the death of a companion is fraught with difficulty. Death is rarely observed in the wild, and it is easy to erroneously attribute human emotions to animals. Nevertheless, several species of intelligent, social animals, such as gorillaschimps and elephants can display particular behaviours when an animal dies - behaviours which some have interpreted as akin to mourning. Taken together with a growing number of reports of cetaceans interacting with dead animals and the discovery that they have specialised neurons linked to empathy and intuition, the Greek study suggests dolphins may have a complex - and even sophisticated - reaction to death.


Scientists Develop Miniaturized Fluorescence Microscope (via GEN)

Scientists have developed a miniaturized integrated fluorescence microscope weighing just 1.9 g, which can be carried around on the head of a freely moving adult mouse. Based on readily mass-produced micro-optics and semiconductor optoelectronics, the instrument incorporates all its optical parts in a 2.4 cm3 housing. The Stanford University designers claim that in comparison with high-resolution fiberoptic technologies, their microscope demonstrates numerous advantages in terms of optical sensitivity, field of view, attainable resolution, cost, and portability, as it doesn’t require optical realignment when transported.

I’m really excited to see what kind of neuron images this tiny microscope will produce.