October 17, 2009
One way to describe brain activity measured by EEG or MEG is by its frequency content. Frequencies can be categorized into one of the following ranges: low, middle and high. The low frequencies include the delta and theta ranges, whereas the middle frequency range consists of the alpha and beta ranges. The gamma wave belongs to the high frequency group.
Different cognitive functions have been associated with these different frequency ranges. Specifically, alpha oscillations have been associated with the inhibition of brain regions that are not required to perform a given task. However, in a past paper, Palva and Palva summarized an accumulating body of evidence that suggested that alpha oscillations play a much larger role in cognition by contributing to mechanisms of attention and consciousness. Click here for full access to the paper.
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October 9, 2009
1/f scaling (or 1/f noise) refers to a scaling relation followed by fluctuations that have been widely observed in nature. 1/f fluctuations have been observed ubiquitously across different disciplines of science (e.g. chemistry, psychology, biology). In specific relation to cognitive neuroscience, 1/f scaling has been observed widely in fMRI measurement series and treated, generally, as noise to work around as opposed to an object of study. The challenge is that since 1/f fluctuations seem to be present throughout the brain, they do not help localize specific cognitive functions to specific areas of the brain. However, studies have shown that the appearance of 1/f fluctuations in fMRI measurements change as a function of cognitive variables.
Whereas some researchers argue that 1/f scaling is a byproduct of processes that are irrelevant to theories of cognition, others argue that 1/f fluctuations reflect a general and essential principle of emergent pattern formation in complex systems, including cognitive systems.
In a past study Kello, Beltz, Holden and Van Orden examined the relevance of 1/f scaling to cognitive function in four experiments using simple and choice response tasks. (For full access to the paper, click here.) The results of this study supported the emergent coordination argument and the researchers concluded that “the generality of 1/f scaling in cognitive performance is evidence that cognitive functions are universally formed as emergent patterns of physiological and behavioral activity”.
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May 19, 2009
From the Dana Foundation: The Dana Foundation released at a news conference on March 4, Learning, Arts, and the Brain, a three-year study at seven universities, which finds strong links between arts education and cognitive development. Speakers included Michael Gazzaniga, Ph.D., UC, Santa Barbara; Michael Posner, Ph.D., University of Oregon; Elizabeth Spelke, Ph.D., Harvard University and Brian Wandell, Ph.D., Stanford University. Guy Mckhann, M.D., Johns Hopkins University gave a summary and Dana Gioia, chairman of the National Endowment for the Arts spoke of the study’s importance to the field of education.
Click here for the webcast archive.
Click here for the event transcript.
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April 17, 2009
Joshua Knobe and Jesse Prinz
Article in Phenomenology and the Cognitive Sciences
Abstract
When people are trying to determine whether an entity is capable of having certain kinds of mental states, they can think of it either from a functional standpoint or from a physical standpoint. We conducted a series of studies to determine how each of these standpoints impact people’s mental state ascriptions. The results point to a striking difference between two kinds of states-those that involve phenomenal consciousness and those that do not. Specifically, it appears that ascriptions of states that involve phenomenal consciousness show a special sort of sensitivity to purely physical factors.
Click here for the complete article.
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April 10, 2009
Ken A. Paller, Joel L.Voss, Carmen E. Westerberg
Article in Perspectives on Psychological Science
Abstract
There is a marked lack of consensus concerning the best way to learn how conscious experiences arise. In this article, we advocate for scientific approaches that attempt to bring together four types of phenomena and their corresponding theoretical accounts: behavioral acts, cognitive events, neural events, and subjective experience. We propose that the key challenge is to comprehensively specify the relationships among these four facets of the problem of understanding consciousness without excluding any facet. Although other perspectives on consciousness can also be informative, combining these four perspectives could lead to significant progress in explaining a conscious experience such as remembering. We summarize some relevant findings from cognitive neuroscience investigations of the conscious experience of memory retrieval and of memory behaviors that transpire in the absence of the awareness of remembering. These examples illustrate suitable scientific strategies for making progress in understanding consciousness by developing and testing theories that connect the behavioral expression of recall and recognition, the requisite cognitive transactions, the neural events that make remembering possible, and the awareness of remembering.
Click here for the full paper.
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February 16, 2009
We often make social comparisons to evaluate others and ourselves. In a recent study in Science, Takahashi and colleagues investigated the neurocognitive mechanisms of envy and schadenfreude (pleasure at another’s misfortune) using fMRI. The researchers found that envy and schadenfreude are associated with different parts of the brain. Whereas envy was associated with the dorsal anterior cingulate cortex, schadenfreude was associated with the ventral striatum. The dorsal anterior cingulate is involved in the processing of cognitive conflicts; envy-related activation in this region was greater when the envied person had superior and more self-relevant characteristics. The ventral striatum is involved in processing reward and the schadenfreude-related activity in this region was stronger when misfortune befell an envied person more so than a neutral person. Additionally, envy-related activity in the anterior cingulate predicted schadenfreude-related activity in the ventral striatum. Takahashi and colleagues suggest that their findings document mechanisms of painful emotion, envy, and a rewarding reaction, schadenfreude.
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February 9, 2009
Meditation can be conceptualized as a complex form of attentional and emotional training that promotes well-being and emotional balance. In most meditation traditions, a common practice is to focus one’s attention to internal body sensations, and many traditions state that this practice results in an increased awareness of internal body sensations. In a study by Khalsa and colleagues, two groups of meditators (Tibetan Buddhist and Kundalini) were compared to a group of nonmeditators on their ability to detect their own heartbeat. (The meditators and nonmeditators were matched for age and body mass index.) Although the investigators predicted that the experienced meditators would outperform the nonmeditators, no such evidence was found. Compared to the nonmeditators, however, the experienced meditators consistently rated the difficulty of the heartbeat detection task as easier and their interoceptive performance as superior. These results suggest that the practice of focusing one’s attention to internal body sensations (a core feature of meditation) does not enhance the ability to sense the heartbeat at rest, but it alters the subjective experience of it.
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January 31, 2009
A. V. Witte, M. Fobker, R. Gellner, S. Knecht and A. Flöel
Article in PNAS
Abstract
Animal studies suggest that diets low in calories and rich in unsaturated fatty acids (UFA) are beneficial for cognitive function in age. Here, we tested in a prospective interventional design whether the same effects can be induced in humans. Fifty healthy, normal- to overweight elderly subjects (29 females, mean age 60.5 years, mean body mass index 28 kg/m) were stratified into 3 groups: (i) caloric restriction (30% reduction), (ii) relative increased intake of UFAs (20% increase, unchanged total fat), and (iii) control. Before and after 3 months of intervention, memory performance was assessed under standardized conditions. We found a significant increase in verbal memory scores after caloric restriction (mean increase 20%; P < 0.001), which was correlated with decreases in fasting plasma levels of insulin and high sensitive C-reactive protein, most pronounced in subjects with best adherence to the diet (all r values < -0.8; all P values <0.05). Levels of brain-derived neurotrophic factor remained unchanged. No significant memory changes were observed in the other 2 groups. This interventional trial demonstrates beneficial effects of caloric restriction on memory performance in healthy elderly subjects. Mechanisms underlying this improvement might include higher synaptic plasticity and stimulation of neurofacilitatory pathways in the brain because of improved insulin sensitivity and reduced inflammatory activity. Our study may help to generate novel prevention strategies to maintain cognitive functions into old age.
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January 17, 2009
From the Dana Foundation: Learning, Arts, and the Brain, a study three years in the making, is the result of research by cognitive neuroscientists from seven leading universities across the United States. In the Dana Consortium study, released in March 2008, researchers grappled with a fundamental question: Are smart people drawn to the arts or does arts training make people smarter?
For the first time, coordinated, multi-university scientific research brings us closer to answering that question. Learning, Arts, and the Brain advances our understanding of the effects of music, dance, and drama education on other types of learning. Children motivated in the arts develop attention skills and strategies for memory retrieval that also apply to other subject areas.
The research was led by Dr. Michael S. Gazzaniga of the University of California at Santa Barbara. “A life-affirming dimension is opening up in neuroscience,” said Dr. Gazzaniga, “to discover how the performance and appreciation of the arts enlarge cognitive capacities will be a long step forward in learning how better to learn and more enjoyably and productively to live. The consortium’s new findings and conceptual advances have clarified what now needs to be done.”
Click here for complete article
Click here to download a a PDF version of the full report (2MB)
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January 9, 2008
 Memory decline in old age may also mean a less vivid imagination. Stitching together personal details gets harder as we get older. Old age does more than stealthily steal away our most cherished memories: it also seems to diminish our ability to imagine things.
This finding, detailed in the January issue of the journal Psychological Science 1, supports the ‘prospective brain’ hypothesis, the idea that imagining the future and remembering the past rely on the same neural machinery.
“One implication of this study is that imagining is quite closely related to, and dependent on, remembering, perhaps more so than we previously realized,” says Dan Schacter of Harvard University.
In the study, Schacter and his team asked groups of young and old participants, with average ages of 25 and 72, respectively, to recount a personal episode from their past or imagine a personal experience in their future in response to cue words.
Nature News
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December 14, 2007
A new issue of Cognition & Emotion is out, including articles on emotional memory and awareness, music and emotions, and anger-induction methods.
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August 29, 2007
 A new issue of Cognition & Emotion is out, including articles on affective processing, affection as a form of cognition, and the interdependence of emotion and cognition.
Cognition & Emotion, Volume 21 Issue 6 2007
How distinctive is affective processing? On the implications of using cognitive paradigms to study affect and emotion
Authors: Andreas B. Eder; Bernhard Hommel; Jan De Houwer
Differentiation in cognitive and emotional meanings: An evolutionary analysis
Authors: Philip J. Barnard; David J. Duke; Richard W. Byrne; Iain Davidson
Affect is a form of cognition: A neurobiological analysis
Authors: Seth Duncan; Lisa Feldman Barrett
On the interdependence of cognition and emotion
Authors: Justin Storbeck; Gerald L. Clore
Can cognitive methods be used to study the unique aspect of emotion: An appraisal theorist’s answer
Author: Agnes Moors
Affect and action: Towards an event-coding account
Authors: Tristan Lavender; Bernhard Hommel
Common valence coding in action and evaluation: Affective blindness towards response-compatible stimuli
Authors: Andreas B. Eder; Karl Christoph Klauer
Mere exposure in reverse: Mood and motion modulate memory bias
Authors: Mark Rotteveel; R. Hans Phaf
Affective distinctiveness: Illusory or real?
Authors: John T. Cacioppo; Gary G. Berntson
Cognition & Emotion
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April 28, 2007
 Declarative memories — memories for facts and events in time — become more resistant to interference during sleep, according to a study that will presented at the 59th Annual Meeting of the American Academy of Neurology (AAN) in Boston, Massachusetts.
“We know that sleep helps boost memory for procedural tasks, such as learning a new piano sequence. But we’re not sure, even though it’s been debated for over a hundred years, whether sleep impacts declarative memory,” said lead author Jeffrey Ellenbogen, MD, a clinical fellow in medicine at Harvard Medical School, in Boston.
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April 23, 2007
 It seems like science still has a ways to go before this question can be answered, but scientists have already started the investigation. In a recent study, Mason and colleagues used fMRI and thought sampling to study which areas of the brain show increased activations in one kind of situation where our minds are likely to wander: when we perform tasks that become banal with continual practice. They compared brain activity that was associated with performing blocks of well-practiced tasks with that of non-practiced, but otherwise identical, tasks and observed greater activation for the practiced tasks in following brain areas: bilateral medial prefrontal cortex (BAs 6, 8, 9, and 10); bilateral superior frontal gyri (BAs 8 and 9); anterior cingulate (BA10); bilateral aspects of the posterior cingulate (BAs 29 and 30); precuneus (BAs 7 and 31); left angular gyrus (BA 39); bilateral aspects of the insula (BA 13); left superior temporal (BA 22), the right superior temporal (BA 41) and the left middle temporal gyri (BA 19). They also found a significant positive relation between changes in brain activity in many of the aforementioned regions for blocks in which subjects performed practiced, relative to non-practiced, tasks and the subjects’ frequency of mind-wandering, which was assessed using the daydream frequency scale of the Imaginal Processes Inventory. Following-up with this intriguing study, it would be interesting to examine the brain activity that arises during specific instances, as opposed to blocks, when participants report mind-wandering.
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March 25, 2007
 Do your thoughts stray from your work or studies? Do you catch yourself making to-do lists when your attention should be elsewhere? Welcome to the club.
College students reported mind-wandering almost one-third of the time in their daily lives, according to a new study led by faculty and graduate students at The University of North Carolina at Greensboro. The study will be published in the July issue of Psychological Science.
The study followed 124 undergraduates, who carried personal digital assistants for a week. The PDAs signaled the students eight times a day between noon and midnight to report whether their thoughts were wandering away from what they were doing and to answer multiple-choice questions about their current activity, surroundings and state of mind.
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