houseofmind:expose-the-light:

The split brain: A tale of two halves

By David Wolman

Since the 1960s, researchers have been scrutinizing a handful of patients who underwent a radical kind of brain surgery. The cohort has been a boon to neuroscience — but soon it will be gone.

Read here

Click on the link for full length article including images, videos and extra references. Sums up split-brain research quite well and it’s open access.

houseofmind:jtotheizzoe:

Explore The Wellcome Collection’s 360-Degree Brain

This interactive tool (go check it out, it spins and zooms and enfoldulates on their website) is like having a brain in a jar on your shelf to study for anatomy class, but much less creepy and less likely to lead to a misunderstood monster roaming the streets of the local village and terrorizing the dreams of young people everywhere.

(ᔥWellcome Collection)

Also: Explore the brain’s beautiful connectome at Cocktail Party Physics!

This is pretty cool. 

neuropsy:

Interactive Human Brain in 3D

Heath­line now offers a cool inter­ac­tive Human Brain in 3D you can play with, as part of their over­all Body Maps. 

(Source: poteau)

neuropsy:

See-Through Brain Tissue

Scientists at Japan’s RIKEN research institute have developed a chemical reagent called Scale that turns biological tissue transparent, allowing them to get a better look at the workings of the brain.

The Scale method combines transparent tissue with fluorescent protein tags, allowing researchers to see specific brain regions at a depth of several millimeters.

Scale doesn’t work on living cells — although a gentler reagent for live tissue is in the works — but it has already been used to study neural networks in mouse brains.

The RIKEN researchers also plan to test Scale on hearts, muscles and kidneys, as well as human biopsy tissue.

Photo shows two mouse embryos. The clear one at right has been rendered transparent by a new chemical reagent developed by Japanese researchers

(via poteau)

The brain that heals itself

Michelle Mack has turned medical thinking upside down.

Born with only half a brain, Mack can speak normally, graduated from high school and has an uncanny knack for dates.

At 27, doctors determined that the right side of her brain had essentially rewired itself to make up for function that was likely lost during a pre-birth stroke. But her childhood and young adult years were fraught with frustration.

CNN: Born with half a brain, woman living full life

Abstract: Animal studies suggest that structural changes occur in the maternal brain during the early postpartum period in regions such as the hypothalamus, amygdala, parietal lobe, and prefrontal cortex and such changes are related to the expression of maternal behaviors. In an attempt to explore this in humans, we conducted a prospective longitudinal study to examine gray matter changes using voxel-based morphometry on high resolution magnetic resonance images of mothers’ brains at two time points: 2– 4 weeks postpartum and 3– 4 months postpartum. Comparing gray matter volumes across these two time points, we found increases in gray matter volume of the prefrontal cortex, parietal lobes, and midbrain areas. Increased gray matter volume in the midbrain including the hypothalamus, substantia nigra, and amygdala was associated with maternal positive perception of her baby. These results suggest that the first months of motherhood in humans are accompanied by structural changes in brain regions implicated in maternal motivation and behaviors.

Click here to download journal article

Source: Kim, P., Mayes, L. C., Wang, X., Leckman, J. F., Feldman, R., & Swaine, J. E. (2010). The plasticity of human maternal brain: Longitudinal changes in brain anatomy during the early postpartum period. Behavioral Neuroscience, 124(5), 695-700.

Further reading:

Kingsley, C. H., & Meyer, E. A. (2010). The contrusction of the maternal brain: Theoretical comment on Kim et al. Behavioral Neuroscience, 124(5), 710-714.

Click here to download journal article

scipsy:

The Capgras Syndrome

In 1923, Capgras and Reboul-Lachaux reported the weird case of a 53-year-old woman who displayed what they called “l’illusion des sosies” a delusional belief that people in her life had been replaced by identical doubles. She claimed that her husband, daughter, and other, were being impersonated and replaced by doubles. She believed that the doubles were part of a plot to steal her property and inheritance and she also believe that there existed doubles of herself (Doran, 1990).

The doubles themselves were replaced by other doubles: 80 times in the case of her husband ( Ellis and Lewis, 2001)

The Capgras delusion is one of the rarest and most colourful syndromes in neurology/psychiatry. The disorder implies that the patient while is often mentally lucid in other respects, comes to regard his parents, children, spouse, siblings or friends, as “imposters”, claiming that the person in question “looks like” or even is “identical to” his father/child/etc, but really isn’t (Hirstein & Ramachandran, 1997). 

In some cases has been observed the delusion that pets and even inanimate objects/places have been replaced by replicas.

Capgras delusion occurs in a variety of settings as a symptom of idiopathic psychiatric illness (e.g. schizophrenia or mood disorders) or of disorders characterized by cerebral dysfunction secondary to structural brain damage or toxicmetabolic conditions (Ellis & Lewis, 2001). Anyway, over a third of the documented cases of Capgras syndrome have occurred in conjuction with a traumatic brain lesions, in particular seems that Capgras syndrome and other misidentification syndromes are more likely to occur with a lesion in the right hemisphere (Granacher, 2003). This fact suggests to some researchers that the syndrome has an organic basis.

Bibliography: 

Doran M. John, The Capgras syndrome: Neurological/Neuropsychological perspectives, 1990

Ellis D. Hadyn & Lewis B. Michael, Capgras Delusion: a window on face recognition, 2001 [pdf]

Granacher P. Robert, Traumatic Brain Injury, 2003.

Hirstein William & Ramachandran V.S., Capgras syndrome: a novel probe for understanding the neural representation of the identity and familiarity of persons, 1997 [pdf]

Thanks to bankofclarity for the suggestion.

Recently, I have been reading up on some research works done by Dr. Vilayanur S. Ramachandran and found it to be really inspiring. I chanced upon this article from Scientific American Mind July/August issue last week and thought that I should share part of the article here. This article generally talk about how something as common as a mirror can help us to understand about the brain and sense of self without using any fancy brain-imaging machines.

I hope it intrigues you as much as it did for me.

Using two bricks, or some duct tape, prop up an 18-inch-square mirror vertically on a table. Sit on that the edge faces you (a). Now put your left hand on the table at the left side of the mirror (either palm up or down) and match your right hand position on the right side. If you now look into the right side of the mirror, you will see the right hand’s reflection optically superimposed in the same place where you feel your left hand to be. (You may need to adjust the position of the left hand to achieve this sensation.) It will now look like you are viewing your own left hand, but of course you are not. Now try the following experiments.

While continuing to look in the mirror on the right side and keeping your left hand perfectly still, move your right hand, wiggle its fingers to make a fist. The “left hand” in the mirror will appear to move in perfect synchrony with the right but, paradoxically, feel completely still. The conflict creates a slight jolt; it feels spooky, sometimes mildly uncomfortable. The brain abhors discrepancies.

Now do the opposite; keep the right hand still and move the left hand. The left hand appears still but feels like it is moving. You will feel the same kind of jarring sensation, but it will be less powerful than in the preceding case. The reason for the asymmetry is not clear.

Why the jolt? The answer resides in the right superior and interior parietal lobules (located above your right ear), where signals from your various senses—visuals, somatic— converge to create your internal sense of body image. Stand up now and close your eyes. Either raise your arms or let them dangle by your side. Obviously you have a vivid sense of being “anchored” in your body except under special circumstances (such as ketamine, anesthesia). Now open your eyes, and you have visual confirmation of what your other senses are telling you: you see your hand where you felt it to be. In short, your senses normally blend different sensory inputs to create a vivid dynamic image of your body moving in space and time.

The mirror experiment you did earlier disrupts this consistency of signals in the right superior parietal lobule. The discrepancy is picked up in part by the right insular cortex (buried in the temporal lobe), and that information is then relayed to the right frontal lobe, where it can be picked up through brain imaging (shown by Richard Frackowiak, Ray dolan and Chris Frith, all at University College London, and Peter Halligan of Cardiff University in Wales).

Source: Ramachandran, V. S., & Rogers-Ramachandran, D. (2011, June 23). Reflections on the mind. Scientific American Mind, 22, 18-22.

(Source: poteau)

cwnl:

Upgrading the Human Brain

Image: Photograph by Andrew Hetherington

Thinking cap records electrical signals from the brain of one-year-old Elise Hardwick, who is helping scientists figure out how the youngest children process sounds that make up the building blocks of language.

Brain studies suggest new ways to improve reading, writing and arithmetic—and even social skills

The technology and research methods of the neuroscientist have started to reveal, at the most basic level, what happens in the brain when we learn something new.

As these studies mature, it may become possible for a preschooler or even an infant to engage in simple exercises to ensure that the child is cognitively equipped for school.

If successful, such interventions could potentially have a huge effect on educational practices by drama­tically reducing the incidence of various learning disabilities.

Scientists, educators and parents must also beware overstated claims for brain-training methods that purport to help youngsters but have not been proved to work.

(via ikenbot)

neuropsy:

New York University neuroscientists have identified the parts of the brain we use to remember the timing of events within an episode. The study, which appears in the latest issue of the journal Science, enhances our understanding of how memories are processed and provides a potential roadmap for addressing memory-related afflictions. Previous research has shown the brain’s medial temporal lobe (MTL) has a significant role in declarative memory—that is, memory of facts and events or episodes. Past studies have shown that damage to the MTL causes impairment in memory for the timing of events within an episode. More specifically, declarative memory is impaired in patients suffering from Alzheimer’s Disease. However, little is known about how individual structures within the MTL remember information about “what happened when” within a particular episode, such as the order of the toasts at a wedding reception or what preceded a game-winning hit in a baseball game.

Their results showed that two main areas of the MTL are involved in integrating “what” and “when”: the hippocampus and the perirhinal cortex. The hippocampus, which is known to have an important role in a variety of memory tasks, provides an incremental timing signal between key events, giving information about the passage of time from the last event as well as the estimated time toward the next event. The perirhinal cortex appeared to integrate information about what and when by signaling whether a particular item was shown first or second in the series.

(Source: esciencenews.com, via poteau)

Best known for his works in behavioral neurology and psychophysics, V.S. Ramachandran has been called “The Marco Polo of neuroscience” by Richard Dawkins and “the modern Paul Broca” by Eric Kandel. It is said that this book would “reveal what the most extreme pathologies can teach us about human nature”. 

Bought this today and can’t wait to start on it!

I would have probably said this more than once but Norman Doidge’s The Brain that Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science has been such a major inspiration in my scholarly pursuit. 

What can you expect from this book?

The brain is a plastic, living organ that can actually change its own structure and function, even into old age. Arguably the most important breakthrough in neuroscience since scientists first sketched out the brain’s basic anatomy, this revolutionary discover, called neuroplasticity, promises to overthrow the centuries-old notion that the brain is fixed and unchanging. The brain is not, as was thought, like a machine, or “hardwired” like a computer.

The result is this book, a riveting collection of case histories detailing the astonishing progress of people whose conditions had long been dismissed as hopeless. We see a woman born with half a brain that rewired itself to work as a whole, a woman labeled retarded who cured her deficits with brain exercises and now cures those of others, blind people learning to see, learning disorders cured, IQs raised, aging brains rejuvenated, painful phantom limbs erased, stroke patients recovering their faculties, children with cerebral palsy learning to move more gracefully, entrenched depression and anxiety disappearing, and lifelong character traits altered.

neuropsy:

Your Brain on God

The article explores the possibility that the perceived presence and feeling of God is simply a product of temporal lobe stimulation. Persinger subjects the author of the article to his ‘God helmet,’ a contraption that stimulates the right temporal lobe with weak magnetic fields. And indeed, the author felt something when the helmet was placed on her head. While it might seem like an oversimplification to claim that spiritual feelings exist only because of neurons firing off, it’s a compelling idea that forces us to truly question what our brains are capable of.

 AIDS Researcher Gail Ironson studied the effects of prayer on HIV patients and found that those who prayed regularly maintained a higher volume of immune cells than those who did not believe in God. These findings may not be conclusive but they are refreshing.

(via Your Brain on God « GLIMPSE journal blog)

(via poteau)

Re: My recent post on ‘Synesthesia’ 

I just want to add on to the post and say that there are many types of synesthesia and within each type, different individuals can report different triggers for their sensation, and differing in intensities in experience. Color-graphemic synesthesia is merely a common form of synesthesia. For example, two individuals who have color-graphemic synesthesia need not share same preferences for the color of each letters.