Chimps solve puzzles for the thrill of it

Small groups of brain cells store concepts for memory formation– from Luke Skywalker to your grandmother

Concepts in our minds – from Luke Skywalker to our grandmother - are represented by their own distinct group of neurons, according to new research involving a University of Leicester neuroscientist.

The research, by neuroscientist Professor Rodrigo Quian Quiroga from the University of Leicester Centre for Systems Neuroscience together with Professor Itzhak Fried, of the UCLA David Geffen School of Medicine, Tel Aviv Sourasky Medical Center and Tel Aviv University, and Professor Christof Koch, of the California Institute of Technology and Allen Institute for Brain Science, Seattle, is featured in a recent article of the prestigious Scientific American magazine.

Recent experiments during brain surgeries have shown that small groups of brain cells are responsible for encoding memories of specific people or objects.

These neurons may also represent different variations of one thing – from the name of a person to their appearance from many different viewpoints.

The researchers believe that single concepts may be held in as little as thousands of neurons or less – a tiny fraction of the billion or so neurons contained in the medial temporal lobe, which is a memory related structure within the brain.

The group were able to monitor the brain activity of consenting patients undergoing surgery to treat epilepsy. This allowed the team to monitor the activity of single neurons in conscious patients while they looked at images on laptop screens, creating and recalling memories.

In previous experiments, they had found that single neurons would ‘fire’ for specific concepts – such as Luke Skywalker – even when they were viewing images of him from different angles or simply hearing or reading his name.

They have also found that single neurons can also fire to related people and objects – for instance, the neuron that responded to Luke Skywalker also fired to Yoda, another Jedi from Star Wars.

They argue that relatively small groups of neurons hold concepts like Luke Skywalker and that related concepts such as Yoda are held by some but not all of the same neurons. At the same time, a completely separate set of neurons would hold an unrelated concept like Jennifer Aniston.

The group believes this partially overlapping representation of related concepts are the neural underpinnings of encoding associations, a key memory function.

Professor Quian Quiroga said: “After the first thrill when finding neurons in the human hippocampus with such remarkable firing characteristics, converging evidence from experiments we have been carrying out in the last years suggests that we may be hitting one of the key mechanisms of memory formation and recall.

“The abstract representation of concepts provided by these neurons is indeed ideal for representing the meaning of the sensory stimuli around us, the internal representation we use to form and retrieve memories. These concepts cells, we believe, are the building blocks of memory functions.”

Fear, anger or pain. Why do babies cry?

Spanish researchers have studied adults’ accuracy in the recognition of the emotion causing babies to cry. Eye movement and the dynamic of the cry play a key role in recognition.

It is not easy to know why a newborn cries, especially amongst first-time parents. Although the main reasons are hunger, pain, anger and fear, adults cannot easily recognise which emotion is the cause of the tears.

"Crying is a baby’s principal means of communicating its negative emotions and in the majority of cases the only way they have to express them," as explained to SINC by Mariano Chóliz, researcher at the University of Valencia.

Chóliz participates in a study along with experts from the University of Murcia and the National University of Distance Education (UNED) which describes the differences in the weeping pattern in a sample of 20 babies between 3 and 18 months caused by the three characteristic emotions: fear, anger and pain.

In addition, the team observed the accuracy of adults in recognising the emotion that causes the babies to cry, analysing the affective reaction of observers before the sobbing.

According to the results published recently in the ‘Spanish Journal of Psychology’, the main differences manifest in eye activity and the dynamics of the cry.

"When babies cry because of anger or fear, they keep their eyes open but keep them closed when crying in pain," states the researcher.

As for the dynamic of the cry, both the gestures and the intensity of the cry gradually increase if the baby is angry. On the contrary, the cry is as intense as can be in the case of pain and fear.

The adults do not properly identify which emotion is causing the cry, especially in the case of anger and fear.

Nonetheless, “although the observers cannot recognise the cause properly, when babies cry because they are in pain, this causes a more intense affective reaction than when they cry because of angry or fear,” outlines Chóliz.

For the experts, the fact that pain is the most easily recognisable emotion can have an adaptive explanation, since crying is a warning of a potentially serious threat to health or survival and thus requires the carer to respond urgently.

Anger, fear and pain

When a baby cries, facial muscle activity is characterised by lots of tension in the forehead, eyebrows or lips, opening of the mouth and raised cheeks. The researchers observed different patterns between the three negative emotions.

As Chóliz notices, when angry the majority of babies keep their eyes half-closed, either looking in apparently no direction or in a fixed and prominent manner. Their mouth is either open or half-open and the intensity of their cry increases progressively.

In the case of fear, the eyes remain open almost all the time. Furthermore, at times the infants have a penetrating look and move their head backwards. Their cry seems to be explosive after a gradual increase in tension.

Lastly, pain manifests as constantly closed eyes and when the eyes do open it is only for a few moments and a distant look is held. In addition, there is a high level of tension in the eye area and the forehead remains frowned. The cry begins at maximum intensity, starting suddenly and immediately after the stimulus.

Scientists make older adults less forgetful in memory tests

Scientists at Baycrest Health Sciences’ Rotman Research Institute (RRI) and the University of Toronto’s Psychology Department have found compelling evidence that older adults can eliminate forgetfulness and perform as well as younger adults on memory tests.

Scientists used a distraction learning strategy to help older adults overcome age-related forgetting and boost their performance to that of younger adults. Distraction learning sounds like an oxymoron, but a growing body of science is showing that older brains are adept at processing irrelevant and relevant information in the environment, without conscious effort, to aid memory performance.

“Older brains may be be doing something very adaptive with distraction to compensate for weakening memory,” said Renée Biss, lead investigator and PhD student. “In our study we asked whether distraction can be used to foster memory-boosting rehearsal for older adults. The answer is yes!”

“To eliminate age-related forgetfulness across three consecutive memory experiments and help older adults perform like younger adults is dramatic and to our knowledge a totally unique finding,” said Lynn Hasher, senior scientist on the study and a leading authority in attention and inhibitory functioning in younger and older adults. “Poor regulation of attention by older adults may actually have some benefits for memory.”

The findings, published online in Psychological Science, ahead of print publication, have intriguing implications for designing learning strategies for the mature, older student and equipping senior-housing with relevant visual distraction cues throughout the living environment that would serve as rehearsal opportunities to remember things like an upcoming appointment or medications to take, even if the cues aren’t consciously paid attention to.

Bilingual children have a better “working memory” than monolingual children

A study conducted at the University of Granada and the University of York in Toronto, Canada, has revealed that bilingual children develop a better working memory –which holds, processes and updates information over short periods of time– than monolingual children. The working memory plays a major role in the execution of a wide range of activities, such as mental calculation (since we have to remember numbers and operate with them) or reading comprehension (given that it requires associating the successive concepts in a text).

The objective of this study –which was published in the last issue of the Journal of Experimental Child Psychology– was examining how multilingualism influences the development of the “working memory” and investigating the association between the working memory and the cognitive superiority of bilingual people found in previous studies.

Executive Functions

The working memory includes the structures and processes associated with the storage and processing of information over short periods of time. It is one of the components of the so-called “executive functions”: a set of mechanisms involved in the planning and self-regulation of human behavior. Although the working memory is developed in the first years of life, it can be trained and improved with experience.

According to the principal investigator of this study, Julia Morales Castillo, of the Department of Experimental Psychology of the University of Granada, this study contributes to better understand cognitive development in bilingual and monolingual children. “Other studies have demonstrated that bilingual children are better at planning and cognitive control (i.e. tasks involving ignoring irrelevant information or requiring a dominant response). But, to date, there was no evidence on the influence of bilingualism on the working memory.

The study sample included bilingual children between 5 and 7 years of age (a critical period in the development of the working memory). The researchers found that bilingual children performed better than monolingual children in working memory tasks. Indeed, the more complex the tasks the better their performance. “The results of this study suggest that bilingualism does not only improve the working memory in an isolated way, but they affect the global development of executive functions, especially when they have to interact with each other”, Morales Castillo states.

Music Education

According to the researcher, the results of this study “contribute to the growing number of studies on the role of experience in cognitive development”. Other studies have demonstrated that children performing activities such as music education have better cognitive capacities. “However, we cannot determine to what extent children perform these activities due to other factors such as talent or personal interest”.

“However, the children in our study were bilingual because of family reasons rather than because of an interest in languages.

Males’ superior spatial ability likely is not an evolutionary adaptation

Males and females differ in a lot of traits (besides the obvious ones) and some evolutionary psychologists have proposed hypotheses to explain why. Some argue, for example, that males’ slight, but significant, superiority in spatial navigation over females – a phenomenon demonstrated repeatedly in many species, including humans – is probably “adaptive,” meaning that over the course of evolutionary history the trait gave males an advantage that led them to have more offspring than their peers.

A new analysis published in The Quarterly Review of Biology found no support for this hypothesis. The researchers, led by University of Illinois psychology professor Justin Rhodes, looked at 35 studies that included data about the territorial ranges and spatial abilities of 11 species of animals: cuttlefish, deer mice, horses, humans, laboratory mice, meadow voles, pine voles, prairie voles, rats, rhesus macaques and talastuco-tucos (a type of burrowing rodent). Rhodes and his colleagues found that in eight out of 11 species, males demonstrated moderately superior spatial skills to their female counterparts, regardless of the size of their territories or the extent to which males ranged farther than females of the same species.

The findings lend support to an often-overlooked hypothesis, Rhodes said. The average superiority of males over females in spatial navigation may just be a “side effect” of testosterone, he said. (Previous studies have shown that women who take testosterone tend to see an improvement in their spatial navigation skills, he said.)

The analysis adds a new dimension to an ongoing debate about the evolutionary significance of some baffling human traits. Rhodes and his colleagues object to “creation stories” that seek to explain sexual phenomena like the female orgasm, rape or menopause by hypothesizing that they evolved because they provided an evolutionary advantage. Some evolutionary psychologists describe rape, for example, as an alternate mating strategy for males who otherwise are reproductively unsuccessful. Others say menopause evolved in women to enhance the survival of their genes by increasing the time spent nurturing their grandchildren. Some of these hypotheses seem intuitive, Rhodes said. “But these stories generally are not testable.”

Researchers tend to overlook the fact that many physical and behavioral traits arise as a consequence of random events, or are simply side effects of other changes that offer real evolutionary advantages, he said.

“For example, women have nipples because it’s an adaptation; it promotes the survival of their offspring,” Rhodes said. “Men get it because it doesn’t harm them. So if we see something that’s advantageous for one sex, the other sex will get it because it’s inheriting the same genes – unless it’s bad for that sex.”

Similarly, scientists who claim that the different spatial skills in men and women are adaptive must explain why women failed to inherit the superior spatial skills of their navigationally enhanced fathers, Rhodes said.

“The only way you will get a sex difference (in an adaptive trait) is where a trait is good for one sex and bad for the other,” he said. “But how is navigation bad for women? This is a flaw in the logic.”

“When people hear arguments made or stories told, particularly about human behaviors being products of adaptation, I think they should ask the question: ‘Where is the evidence?’ ” Rhodes said.

We know when we’re being lazy thinkers

New study shows that human thinkers are conscious cognitive misers

Are we intellectually lazy? Yes we are, but we do know when we take the easy way out, according to a new study by Wim De Neys and colleagues, from the CNRS in France. Contrary to what psychologists believe, we are aware that we occasionally answer easier questions rather than the more complex ones we were asked, and we are also less confident about our answers when we do. The work is published online in Springer’s journal Psychonomic Bulletin & Review.

Research to date on human thinking suggests that our judgment is often biased because we are intellectually lazy, or so-called cognitive misers. We intuitively substitute hard questions for easier ones. What is less clear is whether or not we realize that we are doing this and notice our mistake.

Using an adaptation of the standard ‘bat-and-ball’ problem, the researchers explored this phenomenon. The typical ‘bat-and-ball’ problem is as follows: a bat and ball together cost $1.10. The bat costs $1 more than the ball. How much does the ball cost? The intuitive answer that immediately springs to mind is 10 cents. However, the correct response is 5 cents.

The authors developed a control version of this problem, without the relative statement that triggers the substitution of a hard question for an easier one: A magazine and a banana together cost $2.90. The magazine costs $2. How much does the banana cost?A total of 248 French university students were asked to solve each version of the problem. Once they had written down their answers, they were asked to indicate how confident they were that their answer was correct.

Only 21 percent of the participants managed to solve the standard problem (bat/ball) correctly. In contrast, the control version (magazine/banana) was solved correctly by 98 percent of the participants. In addition, those who gave the wrong answer to the standard problem were much less confident of their answer to the standard problem than they were of their answer to the control version. In other words, they were not completely oblivious to the questionable nature of their wrong answer. The key reason seems to be that reasoners tend to minimize cognitive effort and stick to intuitive processing.

The authors comment: “Although we might be cognitive misers, we are not happy fools who blindly answer erroneous questions without realizing it.”

Indeed, although people appear to unconsciously substitute hard questions for easier ones, in reality, they are less foolish than psychologists might believe because they do know they are doing it.

When Brain Damage Unlocks The Genius Within

Brain damage has unleashed extraordinary talents in a small group of otherwise ordinary individuals. Will science find a way for everyone to tap their inner virtuoso?

Full article

Memory appears susceptible to eradication of fear responses

Fear responses can only be erased when people learn something new while retrieving the fear memory. This is the conclusion of a study conducted by scientists from the University of Amsterdam (UvA) and published in the leading journal Science.

Researchers Dieuwke Sevenster MSc, Dr Tom Beckers and Prof. Merel Kindt have developed a method to determine whether an acquired fear response is susceptible to modification. By doing so, they have revealed the circumstances under which an acquired fear response can be eradicated. In order to measure whether a person actually learnt something new, the researchers used a measure for Prediction Error – in other words, the discrepancy between a person’s anticipation of what is going to happen and what actually happens.

No fear response

Cognitive Behavioural Therapy is currently the most common and effective type of treatment for people suffering from anxiety disorders. However, the effects are often short-lived and the fear returns in many patients. One major finding of Van Kindt’s research lab is that when participants were given propranolol, a beta blocker, while retrieving a specific fear memory, the acquired fear response was shown to be totally erased a day or month later. The researchers repeatedly found that the fear did not come back, despite the use of techniques specifically aimed to make it return. This indicates that the fear memory was either fully eradicated, or could no longer be accessed. One crucial finding was that while participants could still remember the association with the fear, that particular memory no longer triggered the former fear response.

Fear conditioning

For their study the researchers used a fear conditioning procedure in which a specific picture was followed by a nasty painful stimulus. While the participants viewed the pictures, the researchers measured the anticipation of the painful stimulus as well as the more autonomous fear response on the basis of the startle reflex.

The current findings will contribute to the further development of more effective and efficient therapies for patients suffering from excessive anxiety disorders, such as trauma victims. There was no independent measure to indicate whether the memory is susceptible to modification up until now. The researchers have shown that the fear response can be eradicated completely, provided that the person concerned actually learns something new while retrieving the fear memory.

(Image: iStock)

Chimpanzees have faster working memory than humans

Chimpanzees have a faster working memory than humans according to a remarkable study showing that it takes them a fraction of a second to remember something that it would take several seconds for humans to memorise.

A Japanese scientist has demonstrated the prowess of chimps in remembering in less than half a second the precise position and correct sequence of up to nine numbers on a computer screen.

The numbers are shown together randomly distributed on a computer screen and as soon as the chimps press the number “one” the rest of the numerals are masked. However, they can almost invariably remember where each number was.

It is impossible for people to do the same cognitive task that quickly, said Tetsuro Matsuzawa, a primatologist at Kyoto University. “They have a better working memory than us,” he told the American Association for the Advancment of Science meeting in Boston.

Professor Matsuzawa had carried out the memory experiments on a female chimp called Ai, which means “love” in Japanese, and Ayumu, her son who was born in 2000 and has shown even better memory skills, he said.

Professor Matsuzawa suggested that chimps have developed this part of their memory because they live in the “here and now” whereas humans are thinking more about the past and planning for the future.