Do older adults benefit from videogames?

Brain training games claim to boost your mental skills. But while practicing a game might make you better at it, research in young people has shown it doesn’t improve how well you perform other cognitive tasks in everyday life. Now a new study suggests the case may be different for adults above the age of 60. Researchers at the University of California have designed a driving game called NeuroRacer. In this Nature Video, we see how the game can improve an older player’s short-term memory and attention, skills which decline with age.

Read the original research paper here:http://dx.doi.org/10.1038/nature12486 (from Nature)

LOL cats and Neuroscience?

I never expected to see this. Using LOL cats to describe a new study? The result is surprisingly good. Maybe I’m slightly biased because I love cats.

Here’s the abstract of the newly published (31/01) Nature paper in case you want to learn more:

Stroking of the skin produces pleasant sensations that can occur during social interactions with conspecifics, such as grooming1. Despite numerous physiological studies (reviewed in ref. 2), molecularly defined sensory neurons that detect pleasant stroking of hairy skin3, 4 in vivo have not been reported. Previously, we identified a rare population of unmyelinated sensory neurons in mice that express the G-protein-coupled receptor MRGPRB4 (refs 5, 6). These neurons exclusively innervate hairy skin with large terminal arborizations7 that resemble the receptive fields of C-tactile (CT) afferents in humans8. Unlike other molecularly defined mechanosensory C-fibre subtypes9, 10, MRGPRB4+ neurons could not be detectably activated by sensory stimulation of the skin ex vivo. Therefore, we developed a preparation for calcium imaging in the spinal projections of these neurons during stimulation of the periphery in intact mice. Here we show that MRGPRB4+ neurons are activated by massage-like stroking of hairy skin, but not by noxious punctate mechanical stimulation. By contrast, a different population of C fibres expressing MRGPRD11 was activated by pinching but not by stroking, consistent with previous physiological and behavioural data10, 12. Pharmacogenetic activation of Mrgprb4-expressing neurons in freely behaving mice promoted conditioned place preference13, indicating that such activation is positively reinforcing and/or anxiolytic. These data open the way to understanding the function of MRGPRB4 neurons during natural behaviours, and provide a general approach to the functional characterization of genetically identified subsets of somatosensory neurons in vivo.

You can read the paper here (paywall alert).

PS: LOL cats seem to be popular in academia lately. Remember the LOLcat dissertation?

Eye Movements and Lie Detection – Another Myth?

This is not a proper post. It is more like a long tweet. Having done a similar study last year and finding no significant results I felt I had to share this with you.

You have probably heard that right-handed people look up to their right when they are telling a lie, while they look up to their left when they are telling the truth. Surprisingly, even though many people believe this is to be scientifically established, a quick google search comes up with no relevant peer-reviewed papers. Richard Wiseman and colleagues investigated this notion with three different studies. All three studies provided no evidence to support the notion. So it seems that the patterns of eye-movements do not aid lie detection.

Why did this myth survive for such a long time? Probably thanks to psychologists’ reluctance to publish negative results…

Here is the abstract:

Proponents of Neuro-Linguistic Programming (NLP) claim that certain eye-movements are reliable indicators of lying. According to this notion, a person looking up to their right suggests a lie whereas looking up to their left is indicative of truth telling. Despite widespread belief in this claim, no previous research has examined its validity. In Study 1 the eye movements of participants who were lying or telling the truth were coded, but did not match the NLP patterning. In Study 2 one group of participants were told about the NLP eye-movement hypothesis whilst a second control group were not. Both groups then undertook a lie detection test. No significant differences emerged between the two groups. Study 3 involved coding the eye movements of both liars and truth tellers taking part in high profile press conferences. Once again, no significant differences were discovered. Taken together the results of the three studies fail to support the claims of NLP. The theoretical and practical implications of these findings are discussed.

The rest of the article can be found on PLoS ONE.

Brain Disease and Creativity

Readers of this blog probably know I’m very interested in creativity. Recently, I came across a very interesting  review paper on artistry in brain disease by Schott.  Even though, many studies focus on the loss of various abilities as result of brain injury or disease, this review is focused on cases where brain disease resulted in enhanced artistic creativity in people with an interest in art or emergence of artistic creativity in art naive patients. Pictures created spontaneously by patient with brain disease sometimes present an excellent opportunity for studying that disease and revealing underlying mechanisms of cerebral dysfunction. It can also provide some useful information about creative processes in the healthy brain.

Dementia and stroke are very common. However, cases of patients who exhibit enhanced artistic output in these and other neurological disorders are rare or very rare. Miller et al. (2000) showed that enhanced artistry is probably more common but it is often under-reported, since new or preserved visual or musical ability was found in 17% of 69 patients with frontotemporal dementia.
In fact, frontotemporal dementia seems to be the brain disease more closely associated with increased creativity. Miller et al. (1996) were the first to report a patient with frontotemporal dementia that had developed new artistic creativity in the face of advancing dementia. A number of papers (Tanabe et al., 1996; Snowden et al., 1996), as well as Miller at al.’s seminal letter in the Lancet published in the same year brought more attention to the subject of preserved or increased artistic creativity in the presence of brain disease. Miller et al. (1996) described a 68-year-old male with a 12-year history of frontotemporal dementia,who, at the age of 56 years, started to paint having had no previous interest in art.

Patients with Alzheimer’s disease have also been reported to exhibit enhance artistic creativity. Professional painter, Danae Chambers, whose dementia started at around the age of 49 years (Fornazzari, 2005) is a striking example. Even though she was diagnosed with Alzheimer’s disease and her MRI scan revealed mild to moderate brain atrophy, there was no effect on her talent and creativity. However, it should be noted that typically during the progression of the disease stylistic changes leading to frank deterioration and eventual cessation of painting have been reported, especially in professional artists (see Crutch and Rossor, 2006).

In the case of autism there have been several cases of even very young autistics who could produce impressive works of art. A famous example is Stephen Wiltshire, who was able to draw astonishingly faithful architectural representations at the age of 7 years (Sacks, 1995).

According to Schott unexpected artistic creativity experienced by many patients has many features that suggest compulsive behaviour. Moreover, emergence of artistry after brain disease reflects innate rather than learned skills.

The brain correlates of emergent artistic creativity are rather obscure. It appears that dysfunction of the anterior temporal lobes is important if not crucial for the production of unexpectedly enhanced artistry, but the findings are often inconsistent. In some cases frontal lobe involvement is present too (Seeley et al., 2008).  Thus creative drive is thought to increase not only with abnormalities of temporal lobe function and ‘release’ of frontal lobe-mediated creativity, but also by involvement of the dopaminergic mesolimbic system (Flaherty, 2005)

One might wonder; is this emergence of artistic talent observed in patients with various brain diseases really creativity?

De Souza et al. (2010) then concluded: ‘The emergence of artistic talent in patients with fvFTLD is explained by the release of involuntary behaviors, rather than by the development of creative thinking’, and also recommended avoiding consideration of ‘pseudo-creative production, or the emergence of “artistic talent”, as a mastered mental production’.

The author, however, disagrees and concludes:

…the notion of pseudo-creation and identification of ‘artistic talent’ create more difficulties than enlightenment; rather, they emphatically confirm the importance of patients’ pictures. The evidence for creativity surely lies in the creation itself rather than in perfusion patterns or psychological tests.

Schott, G. (2012). Pictures as a neurological tool: lessons from enhanced and emergent artistry in brain disease Brain, 135 (6), 1947-1963 DOI: 10.1093/brain/awr314

Eye Movements as an Objective Measurement of Mind Wandering

We spent a lot of time mind wandering. Cognitive neuroscience has recently started investigating this phenomenon. However, the subjective nature of mind wandering makes capturing and measuring it exceptionally difficult. As a result, there is still no way to objectively measure mind wandering. In the majority of published studies researchers ask participants at random intervals how focused they are on a given task. Uzzaman and Joordens in a recently published paper explored the use of eye movements as an objective measure of mind wandering while participants performed a reading task.

from http://www.eyedoctorguide.com/eye_twitching/the-muscles-of-eye-movement.html

Eye movements are thought to reflect (to some degree) cognitive processes (for a brief overview of eye movement research, see the Scholarpedia entry). Uzzaman et al. study was based on an earlier paper by Reichle, Reineberg, and Schooler (2010) who suggested that eye movements may provide an objective measure of mind wandering. Reichle et al. investigated this hypothesis by comparing the fixation-duration during mind wandering and normal reading episodes. The results were very encouraging and suggested that the participants’ eye movements became progressively decoupled from the ongoing task (i.e., text processing) during mind wandering episodes.

Uzzaman et al. used a reading task coupled with a self-classified probe-caught mind wandering paradigm to obtain a subjective account of mind wandering episodes. They recruited 30 participants who were explicitly informed of the definition of mind wandering episodes prior to the start of the experiment and were instructed that they would be asked to report their mind state at random intervals. The authors defined explicitly mind wandering “as reading without text comprehension, or thinking about anything other than the text on hand”. They also provided several examples to make sure the participants fully understood the concept.

The participants read sixteen pages of “War and Peace” by Tolstoy on a computer screen while their eye movements were tracked and recorded. Randomly every 2–3 min, a probe would appear on top of the text asking what was the mind state of the participants at this specific point. Participants would have to answer to continue the experiment. On average participants received 10 probes in total, in which mind wandering was reported on 49% of them.

The eye movement behaviours of the participants were categorised into mind wandering or reading conditions, based on their self-reports. This analysis was conducted for the 5 s time interval preceding the probe for reading and wandering conditions within each participant. Nine pairs of eye movement variables were analysed (e.g., count of blinks, fixations, saccades, fixation duration, within-word regression count), which displayed different degrees of sensitivity to mind wandering.

Statistical differences were found in two of the eye movement variables, run count and  within-word regression count. Run count was defined as the “the total number of runs, where a run is two consecutive fixations within the same interest-area” and  within-word regression count as “the sum of all fixation durations from when the word was first fixated upon, till the last fixation”.  

Specifically, there were fewer within-word regressions for periods before mind wandering episodes compared to periods before reading reports (z = −2.305, p = 0.021). Also, the total run count was also lower during mind wandering episodes (z = −1.997, p = 0.046). In addition, fixation count, saccade count and total number of saccades within the interest-area were lower during mind wandering reports, although these variables fell slightly short of the conventional significance criterion (all z < −1.755,p > 0.079).

During comprehensive reading all the words were being cognitively processed deeply and effort was put forth. On the contrary, a different pattern was observed during mind wandering episodes, as it was suggested by the lower number and duration of within-word regressions that shows that the  text was not being processed deeply, and as a result limited lexical information was being extracted. As a result, reading became less effortful and more automatic.

The current study revealed a correlation between subjective reports of mind wandering, and objective ocular behaviour. These findings could be further exploited in future studies and lead to the development of algorithms that would mathematically predict the likelihood of mind wandering based on eye movements. Such a development might provide valuable insights into the neural correlates of mind wandering.
Uzzaman, S., & Joordens, S. (2011). The eyes know what you are thinking: Eye movements as an objective measure of mind wandering Consciousness and Cognition, 20 (4), 1882-1886 DOI: 10.1016/j.concog.2011.09.010

Reichle ED, Reineberg AE, & Schooler JW (2010). Eye movements during mindless reading. Psychological science, 21 (9), 1300-10 PMID: 20679524

Music and the Brain: Depression and Creativity Symposium

If you’re following this blog, you probably know that I’m very interested in creativity. I was delighted to find this video on YouTube and decided to share it with you:

Kay Redfield Jamison, professor of psychiatry and behavioral sciences and co-director of the Johns Hopkins Mood Disorders Center at the Johns Hopkins University School of Medicine, convened a discussion of the effects of depression on creativity. Joining Jamison were two distinguished colleagues from the fields of neurology and neuropsychiatry, Dr. Terence Ketter and Dr. Peter Whybrow. The Music and the Brain series is co-sponsored by the Library’s Music Division and Science, Technology and Business Division, in cooperation with the Dana Foundation.

The “Depression and Creativity” symposium marks the bicentennial of the birth of German composer Felix Mendelssohn (1809-1847), who died after a severe depression following the death of his sister, Fanny Mendelssohn Hensel, also a gifted composer.

One of the nation’s most influential writers on creativity and the mind, Kay Redfield Jamison is a noted authority on bipolar disorder. She is the co-author of the standard medical text on manic-depressive illness and author of “Touched with Fire,” “An Unquiet Mind,” “Night Falls Fast” and “Exuberance: The Vital Emotion.”

Dr. Terence Ketter is known for extensive clinical work with exceptionally creative individuals and a strong interest in the relationship of creativity and madness. He is professor of psychiatry and behavioral sciences and chief of the Bipolar Disorders Clinic at Stanford University School of Medicine.

Dr. Peter Whybrow, an authority on depression and manic-depressive disease, is director of the Semel Institute for Neuroscience and Human Behavior at the University of California, Los Angeles (UCLA). He is also the Judson Braun Distinguished Professor and executive chair of the Department of Psychiatry and Biobehavioral Sciences at the David Geffen School of Medicine at UCLA. (description take from here).

And here’s the video:

Ode To The Brain

The Symphony of Science is a musical project of John D Boswell, designed to deliver scientific knowledge and philosophy in musical form. The project owes its existence in large measure to the classic PBS Series Cosmos, by Carl Sagan, Ann Druyan, and Steve Soter, as well as all the other featured figures and visuals. Continuation of the videos relies on generous support from fans and followers.

Read more about the project here.

Here’s one of my favourites, “Ode To The Brain”.

Investigating the Anatomical Relationship Between Primary Sensory and Prefrontal Cortices in the Human Brain

People experience the world in slightly different ways. Philosophers have been writing about this for years and, recently, studies using psychophysics and neuroimaging provide further support for this. A classic example is the way we perceive visual illusions; there is variability in the responses of people about the extent they experience various illusions. Schwarzkopf et al. (2010) showed that inter-individual differences in the surface area of V1 predict individual differences in conscious perception, such as how big something looks.

A study by Chen et al. that was published on the  JoN used a novel approach that combined non-invasive cortical functional mapping with whole-brain voxel-based morphometric analyses to investigate the anatomical relationship between the functionally mapped visual cortices and other cortical structures in healthy humans. Chen et al. found an interesting correlation between the size of V1 and primary auditory cortex. This relationship could be explained in terms of our everyday multisensory experience of the world. However, the size of those areas was anticorrelated with the size of the anterior prefrontal cortex (aPFC), the frontopolar part of the frontal cortex. In a few words, individuals with larger primary visual cortex had larger primary auditory cortex but smaller aPFC. This anticorrelation was only found for the primary sensory cortices and not for other visual cortices (e.g. V2, V3).

According to Chen et al.

…while one might expect a positive correlation between the whole-brain gray matter volume and the volume of its components, instead we found a striking anticorrelation for primary visual cortex: individuals with larger brains tended to have smaller primary visual cortices. In contrast, anterior prefrontal cortex was the single most enlarged region in a larger brain.

The aPFC is a particularly fascinating area. Apart from having many names (anterior PFC, the frontal pole, frontopolar cortex, rostral prefrontal cortex, BA 10…), aPFC is larger relative to the rest of the brain (Semendeferi et al., 2001) and is significantly different in humans compared to other primates (Semendeferi et al., 2001), suggesting that this region may contribute to the unique human behaviour. Furthermore, it is one of the last brain areas to mature in humans (Dumontheil et al., 2008) and has been recently identified as the region with the greatest relative prediction power about brain maturity over development (Dosenbach et al., 2011). Evidence from previous studies suggest that this particular area has a role in higher-order cognitive functions (including prospective memory)

The pairing between the expansion of anterior prefrontal cortex and the contraction of primary sensory cortices reflects a common ground for the formation of anatomically and phylogenetically remote cortical regions, and suggests the existence of a reciprocal link between high-order cognition and low-level sensation.

Future studies will attempt to further investigate this relationship and examine what the effects of these structural differences are on function and performance on various tests thought to tap on those areas.

Song C, Schwarzkopf DS, Kanai R, & Rees G (2011). Reciprocal anatomical relationship between primary sensory and prefrontal cortices in the human brain. The Journal of neuroscience : the official journal of the Society for Neuroscience, 31 (26), 9472-80 PMID: 21715612

Schwarzkopf DS, Song C, & Rees G (2011). The surface area of human V1 predicts the subjective experience of object size. Nature neuroscience, 14 (1), 28-30 PMID: 21131954

Coren S, & Porac C (1987). Individual differences in visual-geometric illusions: predictions from measures of spatial cognitive abilities. Perception & psychophysics, 41 (3), 211-9 PMID: 3575080

Dumontheil I, Burgess PW, & Blakemore SJ (2008). Development of rostral prefrontal cortex and cognitive and behavioural disorders. Developmental medicine and child neurology, 50 (3), 168-81 PMID: 18190537

Semendeferi, K., Armstrong, E., Schleicher, A., Zilles, K., & Van Hoesen, G. W. (2001). Prefrontal cortex in humans and apes: a comparative study of area 10 American journal of physical anthropology, 3 (114), 224-241

Dosenbach NU, Nardos B, Cohen AL, Fair DA, Power JD, Church JA, Nelson SM, Wig GS, Vogel AC, Lessov-Schlaggar CN, Barnes KA, Dubis JW, Feczko E, Coalson RS, Pruett JR Jr, Barch DM, Petersen SE, & Schlaggar BL (2010). Prediction of individual brain maturity using fMRI. Science (New York, N.Y.), 329 (5997), 1358-61 PMID: 20829489

Distractibility is Reflected in the Structure and Function of the Parietal Cortex

Sustaining attention and blocking goal-irrelevant information is a crucial function in everyday life. Kanai and colleagues combining neuroimaging, self-report judgements and TMS found evidence that indicates that a region of the left superior parietal cortex mediates this function.

The ability to avoid distractibility varies across individuals as measured by the Cognitive Failures Questionnaire (CFQ) (Broadbent et al., 1982). Studies on twins and families have showed that the ability to maintain attention in the presence of distractors is highly heritable (Boomsma, 1998). High degree of heritability suggests that the variability might be mediated by genetic influences on the brain, which may be expressed via variability in brain structure.

This hypothesis was tested by Kanai et al. by scanning 145 healthy adult individuals and obtaining their CFQ scores. They used voxel-based morphometry (VBM) to examine whether distractibility scores predicted brain structure. Their results revealed that the level of an individual’s distractibility in everyday life was predicted by variability in regional grey matter density of the left superior parietal lobe (SPL). Highly distractable individuals had larger grey matter density at the left SPL. This particular region has been implicated in top-down attentional control in previous studies (Mevorach et al., 2009). To examine whether there is a causal relationship between this region and distractibility, Kanai et al. applied transcranial magnetic stimulation (TMS) over the left SPL of the participants while they were performing an attentional capture paradigm. The results of the experiment suggest that the left SPL plays a role in suppressing distraction from task-irrelevant salient distractors in both visual fields.

Kanai R, Dong MY, Bahrami B, & Rees G (2011). Distractibility in daily life is reflected in the structure and function of human parietal cortex. The Journal of neuroscience : the official journal of the Society for Neuroscience, 31 (18), 6620-6 PMID: 21543590

Boomsma, D. I. (1998). Genetic analysis of cognitive failures (CFQ): a study of dutch adolescent twins and their parents. Eur. J. Pers., 12(5):321-330.

Broadbent, D. E., Cooper, P. F., FitzGerald, P., and Parkes, K. R. (1982). The cognitive failures questionnaire (CFQ) and its correlates. The British journal of clinical psychology / the British Psychological Society, 21 (Pt 1):1-16.

Mevorach, C., Shalev, L., Allen, H. A., and Humphreys, G. W. (2009). The left intraparietal sulcus modulates the selection of low salient stimuli. Journal of cognitive neuroscience, 21(2):303-315.

Art in the Eye of the Beholder: Preliminary Evidence?

Yellow, Red, Blue by Wassily Kandinsky

Does monocular viewing affect judgement of art? According to a 2008 paper by Finney and Heilman it does. The two researchers from the University of Florida inspired by previous studies investigating the effect of monocular viewing on performance on visual-spatial and verbal memory tasks, attempted to see what the results would be in the case of Art.

 

In particular, they recruited 8 right-eye dominant subjects (6 men and 2 women) with college education and asked them to view monocularly on a colour computer screen 10 painting with the right eye and another 10 with the left. None of the subjects was familiar with the presented paintings. Overall, each subject viewed 5 abstract expressionist and 5 impressionist paintings with each eye. Then they rated on a 1 to 10 scale four qualities of the paintings: representation (=how well the subject of the painting was rendered), aesthetics (how beautiful the painting appeared), novelty (=newness and originality of the painting), and closure (=completeness of the composition). Each quality was defined for each subject.

Monocular viewing had significant effects only in paintings in the abstract expressionist style. Impressionist paintings yielded no differences. The authors attributed this to the more concrete nature of impressionist works. Abstract expressionist paintings were rated more novel when viewed with the left eye. Moreover, the researchers found a trend for rating paintings as having more closure when they were viewed with the right eye than with the left.

The left eye primarily projects to the right superior colliculus and activation of this colliculus activates the right hemisphere’s attentional systems. The authors suggest that the results of the study provide evidence for the role of the right hemisphere in creativity and novelty processing. This seems consistent with previous research on patients with brain lesions and neuroimaging studies that have associated global processing and creativity with the right hemisphere*.

The small number of participants, however, means that the effects observed in this study must be seen with caution. Hopefully, someone will try to replicate these results involving a bigger sample in the near future.

*but also see Lindell (2010)

Finney, G., & Heilman, K. (2008). Art in the Eye of the Beholder: The Perception of Art During Monocular Viewing Cognitive and Behavioral Neurology, 21 (1), 5-7 DOI: 10.1097/WNN.0b013e3181684fe0