Posts tagged psychology
Articles and news from the latest research reports.
Staying on task
Its full name is the Semantic Pointer Architecture Unified Network, but Spaun sounds way more epic. It’s the latest version of a techno brain, the creation of a Canadian research team at the University of Waterloo.
So what makes Spaun different from a mindboggingly smart artificial brain like IBM’s Watson? Put simply, Watson is designed to work like a supremely powerful search engine, digging through an enormous amount of data at breakneck speed and using complex algorithms to derive an answer. It doesn’t really care about how the process works; it’s mainly about mastering information retrieval.
But Spaun tries to actually mimic the human brain’s behavior and does so by performing a series of tasks, all different from each other. It’s a computer model that can not only recognize numbers with its virtual eye and remember them, but also can manipulate a robotic arm to write them down.
Spaun’s “brain” is divided into two parts, loosely based on our cerebral cortex and basil ganglia and its simulated 2.5 million neurons–our brains have 100 billion–are designed to mimic how researchers think those two parts of the brain interact.
Say, for instance, that its “eye” sees a series of numbers. The artificial neurons take that visual data and route it into the cortex where Spaun uses it to perform a number of different tasks, such as counting, copying the figures, or solving number puzzles.
Soon it will be forgetting birthdays
But there’s been an interesting twist to Spaun’s behavior. As Francie Diep wrote in Tech News Daily, it became more human than its creators expected.
Ask it a question and it doesn’t answer immediately. No, it pauses slightly, about as long as a human might. And if you give Spaun a long list of numbers to remember, it has an easier time recalling the ones it received first and last, but struggles a bit to remember the ones in the middle.
“There are some fairly subtle details of human behavior that the model does capture,” says Chris Eliasmith, Spaun’s chief inventor. “It’s definitely not on the same scale. But it gives a flavor of a lot of different things brains can do.”
Brain drains
The fact that Spaun can move from one task to another brings us one step closer to being able to understand how our brains are able to shift so effortlessly from reading a note to memorizing a phone number to telling our hand to open a door.
And that could help scientists equip robots with the ability to be more flexible thinkers, to adjust on the fly. Also, because Spaun operates more like a human brain, researchers could use it to run health experiments that they couldn’t do on humans.
Recently, for instance, Eliasmith ran a test in which he killed off the neurons in a brain model at the same rate that neurons die in people as they age. He wanted to see how the loss of neurons affected the model’s performance on an intelligence test.
One thing Eliasmith hasn’t been able to do is to get Spaun to recognize if it’s doing a good or a bad job. He’s working on it.
Brain-Removal Tool Left in Mummy’s Skull
A brain-removal tool used by ancient Egyptian embalmers has been discovered lodged in the skull of a female mummy that dates back around 2,400 years. Removal of the brain was an Egyptian mummification procedure that became popular around 3,500 years ago and remained in use in later periods. Identifying the ancient tools embalmers used for brain removal is difficult, and researchers note this is only the second time that such a tool has been reported within a mummy’s skull.
The discovery
Located between the left parietal bone and the back of the skull, which had been filled with resin, the object was discovered in 2008 through a series of CT scans. Researchers then inserted an endoscope (a thin tube often used for noninvasive medical procedures) into the mummy to get a closer look and ultimately detach it from resin to which it had gotten stuck.
"We cut it with a clamp through the endoscope and then removed it from the skull," said lead researcher Dr. Mislav Čavka, of the University Hospital Dubrava in Zagreb Croatia, in an interview with LiveScience.
They found themselves peering at an object more than 3 inches (8 centimeters) long that would have been used for liquefying and removing the brain. “It almost definitely would have been used in excerebration [brain removal] of the mummy,” Čavka said.
The instrument would have been inserted through a hole punched into the ethmoid bone near the nose. “Some parts [of the brain] would be wrapped around this stick and pulled out, and the other parts would be liquefied,” Čavka said.
The Egyptian mummy could then be put on its abdomen and the liquid drained through the nose hole. “It is an error that [the] embalmers left this stick in the skull,” said Čavka, adding the tool may have broken apart during the procedure.
This embalming accident, unfortunate for the ancient mummy, has provided researchers with a very rare artifact. Čavka’s team point out in a paper they published recently in the journal RSNA RadioGraphics the only other brain-removal stick found inside a mummy’s skull dates back 2,200 years.
New insights
The stick is quite brittle and the team could not do as thorough of an analysis as they’d hoped. Looking at it under a microscope, botanical experts determined the tool is made from plants in the group Monocotyledon, which includes forms of palm and bamboo.
The most curious find came when the researchers compared their discovery with an ancient account of brain removal made by the Greek writer Herodotus in the fifth century B.C. A visitor to Egypt, he had this to say about how Egyptian brain removal worked (as translated by A. D. Godley, Cambridge, Harvard University Press, 1920, through Perseus Digital Library):
"Having agreed on a price, the bearers go away, and the workmen, left alone in their place, embalm the body. If they do this in the most perfect way, they first draw out part of the brain through the nostrils with an iron hook, and inject certain drugs into the rest."
The recent discovery suggests an organic stick, not an “iron hook,” was used in at least some of these procedures, possibly for economic reasons. Researchers note that the tool found in the skull of the other mummy, dating from 2,200 years ago, was also made of an organic material.
Video-based Test to Study Language Development in Toddlers and Children with Autism
Parents often wonder how much of the world their young children really understand. Though typically developing children are not able to speak or point to objects on command until they are between eighteen months and two years old, they do provide clues that they understand language as early as the age of one. These clues provide a point of measurement for psychologists interested in language comprehension of toddlers and young children with autism, as demonstrated in a new video-article published in JoVE (Journal of Visualized Experiments).
In the assessment, psychologists track a child’s eye movements while they are watching two side by side videos. Children who understand language are more likely to look at the video that the audio corresponds to. This way, language comprehension is tested by attention, not by asking the child to respond or point something out. Furthermore, all assessments can be conducted in the child’s home, using mobile, commercially available equipment. The technique was developed in the laboratory of Dr. Letitia Naigles, and is known as a portable intermodal preferential looking assessment (IPL).
"When I started working with children with autism, I realized that they have similar issues with strangers that very young typical children do," Dr. Naigles tells us. "Children with autism may understand more than they can show because they are not socially inclined and find social interaction aversive and challenging." Dr. Naigles’ approach helps make this assessment more valuable. By testing the child in the home, where they are comfortable, Dr. Naigles removes much of the anxiety associated with a new environment that may skew results.
While this technique identifies some similarities between typically developing toddlers and children with autism spectrum disorder, such as understanding some types of sentences before they produce them, this does not mean that these children are the same. “Some strategies of word learning that typical children have acquired are not demonstrated in children with autism.” Dr. Naigles says. By illuminating both strengths and weaknesses, the test is valuable for assessing language development. “JoVE is useful because in the past, I have gone to visit various labs to coach them in putting together an IPL. JoVE will enable other labs to set up the procedure more efficiently.” JoVE associate editor Allison Diamond stated, “Showing this work in a video format will allow other scientists in the field to quickly adapt Dr. Naigles’ technique, and use it to address the question of language development in autism, an extremely important field of research.”
Want Your Baby to Learn? Research Shows Sitting Up Helps
From the Mozart effect to educational videos, many parents want to aid their infants in learning. New research out of North Dakota State University, Fargo, and Texas A&M shows that something as simple as the body position of babies while they learn plays a critical role in their cognitive development.
The study shows that for babies, sitting up, either by themselves or with assistance, plays a significant role in how infants learn. The research titled “Posture Support Improves Object Individuation in Infants,” co-authored by Rebecca J. Woods, assistant professor of human development and family science and doctoral psychology lecturer at North Dakota State University, and by psychology professor Teresa Wilcox of Texas A&M, is published in the journal Developmental Psychology®.
The study’s results show that babies’ ability to sit up unsupported has a profound effect on their ability to learn about objects. The research also shows that when babies who cannot sit up alone are given posture support from infant seats that help them sit up, they learn as well as babies who can already sit alone.
“An important part of human cognitive development is the ability to understand whether an object in view is the same or different from an object seen earlier,” said Dr. Woods. Through two experiments, she confirmed that 5-and-a-half- and 6-and-a-half-month-olds don’t use patterns to differentiate objects on their own. However, 6-and-a-half-month-olds can be primed to use patterns, if they have the opportunity to look at, touch and mouth the objects before being tested.
“An advantage the 6-and-a-half-month-olds may have is the ability to sit unsupported, which makes it easier for babies to reach for, grasp and manipulate objects. If babies don’t have to focus on balancing, their attention can be on exploring the object,” said Woods.
In a third experiment, 5-and-a-half-month-olds were given full postural support while they explored objects. When they had posture support, they were able to use patterns to differentiate objects. The research study also suggests that delayed sitting may cause babies to miss learning experiences that affect other areas of development.
“Helping a baby sit up in a secure, well-supported manner during learning sessions may help them in a wide variety of learning situations, not just during object-feature learning,” Woods said. “This knowledge can be advantageous, particularly to infants who have cognitive delays who truly need an optimal learning environment.”
Placebo and the Brain: How Does it Work?
Placebo, the positive effect of a drug that lacks any beneficial ingredients, has been researched for centuries but remain a mystery for psychologists and neuroscientists alike. Although there is now a considerable amount of amassed knowledge of how placebo can be induced, through which mechanisms it works, and which individuals are susceptible to the effect, the explicit answer to why and how our brains have the ability to ‘cure’ themselves under certain circumstances is yet to be found. Having dived into the literature on the phenomenon, a picture has emerged in which one of the brain’s greatest tricks can be better understood and the fascinating implications it has for how we look at the body-mind distinction.
What is termed a placebo is usually defined in research trying to pin down its nature as the treatment that results in a change in symptom or condition that differs from the natural course of the specific disease. Placebo effects have been shown for mainly relief of pain, but also in studies of depression, parkinson’s, and anxiety. While the sugar pill is still in use, we now know that there are a two factors that are crucial for a placebo effect to occur. These are the level of expectancy and desire to get better/not get worse that the patient feels and both are in turn sensitive to a host of psychosocial variables such as their faith in medical staff, the emotional tone of the physician-patient interaction (whether it is optimistic or pessimistic for example), memories of past experiences with the effects of medicine, and so on.
While some individuals show reliable placebo effects, others do not and the underlying causes have recently been suggested to be tied to our individual genetic makeup. Researchers from the Harvard Program for Placebo Studies found that the magnitude of the placebo effect was tied to genes coding for an anzyme that regulates the levels of dopamine in various regions of the brain. Dopamine plays a key role in processing of reward, pain, memory, and learning, all areas in which the placebo effect has been demonstrated. The study, led by Kathryn Hall, concluded that persons whose genes promote an upregulation of the levels of dopamine in the brain also exhibit the greatest placebo effects. In other studies examining release of another group of transmitters called opioids, which regulate the activity in areas that code for pain, higher amounts of opioids were matched to the size of the placebo effect found.
As for where the effect originates, research using brain imaging have found that when a real drug is compared to the effects of a placebo very similar areas show activation but some areas, such as the lateral and central prefrontal cortex, show a greater response in the placebo condition. This part of the brain is often described as overseeing and exerting control over other processing in the brain and act as a connecting point for different streams of information that build up our expectations and desires.
So, how can this knowledge about the placebo effect influence the way doctors discuss, promote, and administer their own treatments? Surely, if we know that an encouraging prognosis given together with a sugar pill can be as effective in some cases as a pharmacological product but without the side- effects, we should be using that. However, having doctors treat their patients through deception leads to obvious problems such as public mistrust in the profession. A finding from the scientists at the very same Harvard program for placebo studies might have the answer. They namely demonstrated that the placebo effect remained when participants were told explicitly that the treatment they were given was in effect useless.
The split brain: A tale of two halves
In the first months after her surgery, shopping for groceries was infuriating. Standing in the supermarket aisle, Vicki would look at an item on the shelf and know that she wanted to place it in her trolley — but she couldn’t. “I’d reach with my right for the thing I wanted, but the left would come in and they’d kind of fight,” she says. “Almost like repelling magnets.” Picking out food for the week was a two-, sometimes three-hour ordeal. Getting dressed posed a similar challenge: Vicki couldn’t reconcile what she wanted to put on with what her hands were doing. Sometimes she ended up wearing three outfits at once. “I’d have to dump all the clothes on the bed, catch my breath and start again.”
In one crucial way, however, Vicki was better than her pre-surgery self. She was no longer racked by epileptic seizures that were so severe they had made her life close to unbearable. She once collapsed onto the bar of an old-fashioned oven, burning and scarring her back. “I really just couldn’t function,” she says. When, in 1978, her neurologist told her about a radical but dangerous surgery that might help, she barely hesitated. If the worst were to happen, she knew that her parents would take care of her young daughter. “But of course I worried,” she says. “When you get your brain split, it doesn’t grow back together.”
In June 1979, in a procedure that lasted nearly 10 hours, doctors created a firebreak to contain Vicki’s seizures by slicing through her corpus callosum, the bundle of neuronal fibres connecting the two sides of her brain. This drastic procedure, called a corpus callosotomy, disconnects the two sides of the neocortex, the home of language, conscious thought and movement control. Vicki’s supermarket predicament was the consequence of a brain that behaved in some ways as if it were two separate minds.
After about a year, Vicki’s difficulties abated. “I could get things together,” she says. For the most part she was herself: slicing vegetables, tying her shoe laces, playing cards, even waterskiing.
But what Vicki could never have known was that her surgery would turn her into an accidental superstar of neuroscience. She is one of fewer than a dozen ‘split-brain’ patients, whose brains and behaviours have been subject to countless hours of experiments, hundreds of scientific papers, and references in just about every psychology textbook of the past generation. And now their numbers are dwindling.
Through studies of this group, neuroscientists now know that the healthy brain can look like two markedly different machines, cabled together and exchanging a torrent of data. But when the primary cable is severed, information — a word, an object, a picture — presented to one hemisphere goes unnoticed in the other. Michael Gazzaniga, a cognitive neuroscientist at the University of California, Santa Barbara, and the godfather of modern split-brain science, says that even after working with these patients for five decades, he still finds it thrilling to observe the disconnection effects first-hand. “You see a split-brain patient just doing a standard thing — you show him an image and he can’t say what it is. But he can pull that same object out of a grab-bag,” Gazzaniga says. “Your heart just races!”
Brain cells activated, reactivated in learning and memory
Memories are made of this, the song says. Now neuroscientists have for the first time shown individual mouse brain cells being switched on during learning and later reactivated during memory recall. The results are published Dec. 13 in the journal Current Biology.
We store episodic memories about events in our lives in a part of a brain called the hippocampus, said Brian Wiltgen, now an assistant professor at the Center for Neuroscience and Department of Psychology at the University of California, Davis. (Most of the work was conducted while Wiltgen was working at the University of Virginia.) In animals, the hippocampus is important for navigation and storing memories about places.
"The exciting part is that we are now in a position to answer a fundamental question about memory," Wiltgen said. "It’s been assumed for a long time that the hippocampus is essential for memory because it drives reactivation of neurons (nerve cells) in the cortex. The reason you can remember an event from your life is because the hippocampus is able to recreate the pattern of cortical activity that was there at the time."
According to this model, patients with damage to the hippocampus lose their memories because they can’t recreate the activity in the cortex from when the memory was made. Wiltgen’s mouse experiment makes it possible to test this model for the first time.
Rhesus monkeys cannot hear beat in music
Beat induction, the ability to pick up regularity – the beat – from a varying rhythm, is not an ability that rhesus monkeys possess. These are the findings of researchers from the University of Amsterdam (UvA) and the National Autonomous University of Mexico (UNAM), which have recently been published in the scientific journal PLOS ONE.
The research conducted by Henkjan Honing, professor of Music Cognition at the UvA, and a team of neurobiologists headed by Hugo Merchant from the UNAM, shows that rhesus monkeys cannot detect the beat in music, although they are able to detect rhythmic groups in music. The results of this research support the view that beat induction is a uniquely human, cognitive skill and contribute to a further understanding of the biology and evolution of human music.
(Photograph by Shane Moore)
Infants process faces long before they recognize other objects
New research from psychology Research Professor Anthony Norcia and postdoctoral fellow Faraz Farzin, both of the Stanford Vision and NeuroDevelopment Lab, suggests a physical basis for infants’ ogling. At as early as four months, babies’ brains already process faces at nearly adult levels, even while other images are still being analyzed in lower levels of the visual system.
The results fit, Farzin pointed out, with the prominent role human faces play in a baby’s world.
"If anything’s going to develop earlier it’s going to be face recognition," she said.
The paper appeared in the online Journal of Vision.
The researchers noninvasively measured electrical activity generated in the infants’ brains with a net of sensors placed over the scalp – a sort of electroencephalographic skullcap.
The sensors were monitoring what are called steady state visual potentials – spikes in brain activity elicited by visual stimulation. By flashing photographs at infants and adults and measuring their brain activity at the same steady rhythm – a technique Norcia has pioneered for over three decades – the researchers were able to “ask” the participants’ brains what they perceived.
When the experiment is conducted on adults, faces and objects (like a telephone or an apple) light up similar areas of the temporal lobe – a region of the brain devoted to higher-level visual processing.
Infants’ neural responses to faces were similar to those of adults, showing activity over a part of the temporal lobe researchers think is devoted to face processing.
Bryan Saunders, a performance and visual artist, undertook a high profile experiment in creativity, starting several years ago whereby, according to the artist, he created a series of self-portraits, each one done under the influence of a different substance—pretty much an A to Z assortment, from prescription meds like Abilify and Xanax to crystal meth. Over the weeks he’d create amazing pieces, suffer mild brain damage and end up hospitalized—all for the sake of art and creation.