New Neuromorphic chip mimics human brain

Synapse

Synapse: creative commons licensed (BY-NC-ND) flickr photo by tsevis: http://flickr.com/photos/tsevis/9501837486

The neuromorphic chip – so called due to its brain-like processing abilities – has been created on a production-scale in a joint project by IBM and Cornell University.

The new chip acts like a brain, of sorts. Each chip is made up of 5.4 billion transistors with 1 million electronic neurons that talk to each other via 256 synapses.

Today’s world

Today’s computing is based on the computer chip created by John von Neumannover 70 years ago. The humble chip performs two tasks; processing data and holding memory. Just the job for many simple data processing tasks, however, yet not able to perform advanced tasks, such as language or vision. Continue reading

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Temporary Simulated Blindess Can Help Restore Hearing, Study Finds

connection

Minimizing sight for as little as a week can improve the brain’s ability to processs hearing, say neuroscientists at John Hopkins University. The findings, published in the journal the Neuron, could help patients with hearing loss to regain a level of hearing.

According to researchers, sensory systems do not work in isolation: instead, they show interactions that are specifically uncovered during sensory loss.

Using mice, the research team analysed the neural connections in the brain that manage vision and hearing to explore how the connections worked together to support each sense. Continue reading

I Know Why the Caged Bird Sings: Testosterone, Desire and the Pull of a Canary

Canary and mating songTestosterone increases the urge to sing yet decreases the quality of birdsong, according to research at John Hopkins University.

Increasing testosterone levels in the brain demonstrated an increase in the desire to sing and volume of song, yet reduced the size of a separate area in the brain that regulates song quality.

The findings on testosterone and its affect on the brain are hoped to further understanding of how the hormone testosterone acts in the human brain to regulate speech, and how anabolic steroids (prescription drugs used to increase testosterone levels) affect human behaviour.

The ability of a male canary to sing a pitch-perfect song is essential in wooing a female canary. The quality and frequency of song changes through the seasons and it is the hormone testosterone which plays a major role in changing song behaviour.

To determine how testosterone influences birdsong, researchers divided 20 canaries into two groups to receive a hormone implant:

  • group one received testosterone in the medial preoptic nucleus, or POM (an area in the hypothalamus responsible for sexual motivation in animals and humans)
  • group two received testosterone that acted throughout the whole of the brain
  • group three was a control group and received no hormone treatment at all

Both of the groups that received testosterone treatment (group one and two) sang. However researchers noticed that in some cases in group two the canaries’ songs were sung poorly. The birds that only received testosterone to the POM area (group two) sang at high rates, but could not produce high quality song that is most attractive to females. Lead researcher, Dr. Alward, commented:

Our data suggests that testosterone needs to act in different areas of the brain to regulate the specific components of this complex social phenomenon. It appears that, like in so many other species, testosterone in the POM can regulate an animal’s motivation, in this case, the motivation to sing.

However, singing and courting a female is more than just motivation. There is the quality of the song that is required to successfully attract a mate and then the process of attending to the female, or singing to her, when she is there which requires the coordination of multiple brain regions.”

The canaries that received testosterone throughout the brain displayed high-quality typical canary vocalization behaviour –  consistent with the idea that testosterone acts on several different brain areas to regulate how much as well as how well the birds can sing.

The researchers say these results have broad implications for research concerning how steroid use in humans affects sexual behaviours and how hormones regulate the difference components of speech in humans. Dr Alward added:

The hormones in these birds are identical to those in humans and they can regulate brain changes in a similar manner.”

Notes:

John Hopkins University Press Release: Testosterone in male songbirds may enhance desire to sing but not song quality

PNAS: Differential effects of global versus local testosterone on singing behaviour and its underlying neural substrate

Image: thanks to Flickr

Childhood Maltreatment Reduces Fear Circuit Connectivity, Study Shows

Circuit board imageA study by the University of Wisonsin – one of the first to examine altered fear circuitry connectivity in  relation to childhood maltreatment – has found significant evidence of changes to brain circuit connectivity in response to childhood abuse.

The findings, published in PNAS, hope to further the understanding of the commonly accepted link between childhood abuse and internalising disorders such as depression developing in adolescence and adulthood.

Childhood maltreatment has long been identified as a major risk factor in developing depression later in life, yet little is known about the alteration of connectivity of the brain’s fear circuitry – an important candidate mechanism linking abuse and the development of internalising disorders.

To examine the inner workings of fear circuitry researchers used fMRI (functional magnetic resonance imaging) to detect the resting state functionality of brain connectity. The resting state is a method of exploring the brain’s functional organization and to examine if it is altered in cases of neurological or psychiatric disease.

64 young participants in a longitudinal community study were studied to link:

  • experiences of maltreatment during childhood
  • the resting state of functional brain connectivity
  • evidence of the development of internalising symptoms

Results showed that connectivity of fear circuitry in the brain is significantly affected by experiences of maltreatment. Both males and females showed reduced connectivity in the fronto-hippocampal area (hippocampus-subgenual cingulate) yet only females showed evidence of additional altered connectivity within the fronto-hippocampal area and also the lower prefrontal -amygdala (amydala- subgenual).

The hippocampus – named after its visual resemblance to the sea horse (hippo meaning “horse” and kampus meaning “sea monster”) is a major component of the brain and plays an important role in processing information from short-term memory to long-term memory.

Study highlights:

  • lower hippocampussubgenual cingulate resting- states functional connectivity in both adolescent females and males (also known as area 25 )
  • lower function in the amygdala subgenual cingulate resting state-functional connectivity in females only
  • resting-state functional connectivity mediated the association of maltreatment during childhood with adolescent internalizing symptoms

Maltreatment in childhood, even at the lower severity levels found within a community sample, may alter the regulatory capacity of the brain’s fear circuit and lead to increased internalizing symptoms by late adolescence. Neuropsychologist and lead researcher, Dr Herringa, said:

Findings highlight the importance of fronto-hippocampal connectivity for both sexes in internalizing symptoms following mal- treatment in childhood. The impact of maltreatment during childhood on both frontoamygdala and hippocampal connectivity in females may help explain their higher risk for internalizing disorders such as anxiety and depression.”

Notes:

PNAS document: Childhood maltreatment is associated with altered fear circuitry and increased internalizing symptoms by late adolescence

Image credit: with thanks to RGB Freestock Cris DeRaud

I Like What I Like: The Science of Art Appreciation

art, cherub,

The appreciation of art has commonly been thought of as highly personable and illogical. Research, however, suggests that the appreciation of art may be as open to the laws of science as the eyes that perceive it.

Dr K.Lindell of La Trobe University, Australia, and Dr Mueller of the University of Vienna, Austria, have collated research investigating the psychology behind visual art in,
” Can science account for taste? Psychological insights into art appreciation,” published in the Journal of Cognitive Psychology.

Breaking down the experience of viewing art by “bottom up” and “top down” variables, the paper explores the influence of variables on a viewer’s preference examining the extent to which psychological research can account for art appreciation.

“Bottom up” variables of art that had an impact on the viewer included abstraction, form, complexity and symmetry.

“Top-down” influences included artwork, novelty, and viewer expertise.

Summary

The collation of studies investigating the psychology of art found that bottom up and top down variables reliably influenced a viewer’s preference. In studies that used fMRI imaging of the brain, regions involved in reward and emotion were seen to be highly active when viewing art that was considered as aesthetically pleasing.

  • viewers favoured representational over abstract artworks, and these were seen to activate reward regions in the brain
  • activation in the occitipital gyri and the left cingulate sulcus – regions involved in the evaluation of emotive stimuli i,.e, pictures
    and faces, were seen to increase in activity in direct correlation with aesthetic preference.
  • activation in the right cauduate nucleus – part of the brain linked with reward-based behavioural learning, decreased in direct correlation with a viewer’s decreasing art preference
  • paintings considered “beautiful” stimulated two areas; the anterior cingulate and left parietal cortex – regions involved in pleasurable emotional states and the activation of the orbitofrontal cortex – an area involved in the perception of rewarding stimuli.

The findings go towards explaining the popular distaste for modern art. Lost in translation, abstract art has a low level of representation – a significant “bottom up” variable which affects the viewer’s experience. The challenge of interpreting a piece of modern art can overwhelm the viewer, and when meaning is lost, aesthetic pleasure is reduced.

Few studies have attempted before to establish a connection between the brain and the aesthetic experience. The research suggests that there would be an increased understanding gained in the experience of being human from further study.  Dr K Lindell, lead researcher, comments:

By establishing the commonalities between viewing artworks and other pleasing stimuli, researchers could potentially unwrap what distinguishes an ‘‘aesthetic experience’’ from a straightforward pleasurable experience. In doing so, further light may be shed on the cortical basis of aesthetics.”

Notes:

View the ten greatest works of art –  http://www.biographyonline.net/artists/10-greatest-works-art.html

Journal of Cognitive Psychology: Can science account for taste? Psychological insights into art appreciation

Image: with thanks to RGB Free Stock

Poverty, the Brain and “Executive Thought”

executive thought

The number of children starting life in poverty in the UK is rising according to a report by the Commission on Social Mobility and Child Poverty.

According to government figures from 2011/12, as many as 3.5 million children in the UK (27%) were living in households with incomes 60% below the average net disposable household income after housing costs.

Theresa Marteau, Director of UK Cambridge University’s Behaviour Unit, and Associate Professor Peter Hall of the University of Waterloo in Canada, highlight the link between environment and the brain in poverty in the British Medical Journal’s Editorial.

Co-authors of Breadlines, brain, and behaviour suggest methods of loosening the link between poverty and demography by targeting both the environment and the brain’s “executive functioning” – the theorized network thought to link to the prefrontal cortex determining behaviour by inhibiting impulsive responses and focusing attention, and thought to be less well developed in children and adults living in poverty.

This lesser developed functioning, research suggest, leads to a vulnerability for those living in poverty to be less able to control negative behaviours that damage health. Theresa Marteau, co-author comments:

Given the links between poverty, brain development, and behaviour, these children start life with a higher chance than their more fortunate peers of behaving in ways that will harm their health and reduce their life expectancy.”

The association of executive functioning may contribute to higher rates of smoking, drinking, poor diet, and physical inactivity within deprived communities. The social clustering of these behaviors may explain the contrasting life expectancy in wealthy and the most deprived communties.

For example, the BBC report that Glasgow in Scotland continues to have the lowest life expectancy in the UK. Figures taken from the Office for National Statistics show that men in the city live to an average age of 71 and women to 78. This compares to 85 for men and 87 for women in the highest UK areas – Kensington and Chelsea in London.

Executive function is thought to continue to develop after childhood and can continue to be affected within adulthood. Numerous studies show that there is a significant plasticity in the prefrontal cortex suggesting that it may be possible to improve the development of executive functioning at any stage in human life.

There is a “double hit” however for those in poverty – one within the brain in terms of lesser developed executive function, and the other on the doorstep in terms of environmental triggers.

Deprived areas are typically environments which consist of triggers for poor health choices, for example easy access to nutrient-poor foods, alcohol and a limited access to physical access and green spaces.

Being born into an environment which is more likely to encourage negative behaviours, together with a reduced capacity to resist them are seen to give those in poverty a “double hit” – yet one which can be harnessed for positive interventions –

Together with interventions that target brains, those that target
environments could reduce the double hit faced by those born
into poverty: living in environments that contain more cues for
unhealthier behaviours, coupled with a reduced capacity to
inhibit responses to those cues.”

The suggestions for increasing executive functioning include aerobic exercise, computer based brain training, supplementing incomes or providing parental support programmes. This, together with eliminating environmental cues were proposed as ways to inhibit the impact of poorly developed executive functioning.

The findings of research to further develop executive functioning are yet to be proven yet researchers hope that the strategies that target the environment and the brain may work towards breaking down poverty clusters. 

The report concludes –

Although the number of children born into poverty in the UK and elsewhere is high and may be rising, a broadening array of findings from brain and behavioural sciences suggest novel targets for intervention to reduce the strength of association between “demography and destiny.”

Notes:

Breadlines, brains, and behaviour

Commission on Social Mobility and Child Poverty

Glasgow has the lowest life expectancy in the UK (BBC article)

Households below average income (HBAI)

Image credit: with thanks to mzacha RGB Free Stock

Brain Trickery, Body Ownership and the Sense of Self Gone Awry

trick

A study by the Sackler Centre for Consciousness Science found that a virtual-reality hand set to pulse in time to the beat of a heart creates the illusion of body ownership – the brain believes that the virtual hand is part of its own body.

Easily hoodwinked, the brain was first proved to accept a foreign hand as its own in 2009 in the now classic “rubber hand illusion.” The easily re-created trickery involved a blown up washing up glove, and a feather. With the rubber hand out of sight and only the sensory stimuli to go by, the brain soon perceived the rubber hand as part of the body as the hand was stroked at the same time as the real hand.

The experiment by Dr. Keisuke Suzuki and Prof. Anil Seth, was  a virtual reality version of the rubber hand illusion and further explored the foundations of “proprioception” – the human cocktail of sense, touch and brain signals which create the experience of being in the body – the very foundation of self consciousness.

The researchers added a “cardio” element to the “rubber hand” illusion by using a unique combination of heartbeat monitoring and augmented reality which created a “cardio-visual” version of the rubber hand illusion.

21 volunteers participated in the study, involving the following steps:

  • Participants wore a head-mounted display to facilitate the augmented reality in front of them
  • The participants’ real hand was hidden from their visual field and attention drawn instead to the cardio-visual hand
  • A virtual-reality, cardio-visual version of the participants’ own hands was projected onto a screen in front of them
  • The cardio-virtual hand pulsed from red to black in time with the participants’ own heartbeats.

Results showed that the participants experienced the virtual hand as part of their body more frequently when the pulses were synchronized with their actual heartbeat, compared with when the pulses were out of synch.

The results show that the brain incorporates its impression of the body externally into its impression internally when determining what is actually happening to the body.

The experiment also showed that the accurate visual feedback of intentional hand movements provides a powerful prompt for the experience of body ownership that can surpass the influence of cardio-visual feedback.

The new findings, published in Neuropsychologia could lead to developments in the treatment of anxiety and body image disorders. If the body can trick itself into believing a rubber hand is its own, then perhaps it can believe a normal equilibrium of well being when before there was none.

Prof. Anil Seth says:

“The findings tie in with our research at the Sackler Centre showing that many other perceptual and cognitive processes can be affected by the beating of the heart in ways that have important implications for clinical conditions such as anxiety and disorders of body image.

Our results showed that the illusional experience of the body is associated with the individual interoceptive sensitivity (sensitivity to stimuli originating inside of the body).  Although this sensitivity is not easy to be trained, it was reported that meditation possibly changes the interoceptive representation in our brain. As used in this study, experiencing the own heartbeat in visually salient ways might influence people’s interoceptive perception, which may help the anxiety disorder patients caused by the low interoceptive sensitivity.”

Notes:

Press Release: Sussex University, Sackler Centre for Consciousness Science
http://www.sussex.ac.uk/newsandevents/?id=20645

Create your own “rubber hand” illusion (New Scientist)
http://www.newscientist.com/article/dn16809-body-illusions-rubber-hand-illusion.html

Image credit: thanks to Mzacha of RGB Freestock
http://www.rgbstock.com/user/mzacha