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Showing posts with label executive control. Show all posts
Showing posts with label executive control. Show all posts

Wednesday, February 03, 2016

Training the Brain to Control Negative Emotions

The human brain contains a distinct network that serves as its executive agent. This network is primarily based in the dorsolateral prefrontal, parietal, and cingulate cortices. It regulates the many “top down” neurobehavioral functions that are so characteristic of human brain. Deficiencies in the function of this network underlie numerous neuropsychiatric conditions, but even underlie much of the failings of us all. The ability to regulate emotions and direct rational actions is typically associated with success in life, and inability to do so often leads to dire consequences.
This network can be trained to develop more robust capacity for executive control. This, as we all experience, is what parenting and schooling are about. Such training is especially crucial in early childhood when the challenges of school are first encountered. Even so, such training takes many years and for most of us may never be completed.
The question arises: can such executive control training be expedited? One possibility has recently arisen from several studies showing that working memory capacity can be expanded by a relatively short training time, and in the process general intelligence may be improved. Since the same system that determines intelligence is also operative in executive control, it seems reasonable that working memory training might also enhance executive control. To pursue this possibility in a specific context, researchers have hypothesized that inappropriate or maladaptive behaviors might be reduced by effective working memory training based on emotion-laded stimuli.
In a study by Suaznne Schweizer and colleagues in England, subjects in their early 20s were assessed for emotional control before and after 20 training days of 20-30 minute sessions. The experimental groups received dual n-back training with a simultaneously presented face and a word that was either emotionally negative or neutral. After each picture-word pair, subjects were to press a button to indicate if either or both members of the pair matched the stimulus presented n-positions back. Tests began with n = 1 and increased as subjects gain proficiency.
Not surprisingly, errors in both trained and untrained subjects increased at levels beyond n = 1, and the error rate was comparable for both groups. Results also indicated that subjects reported less distress when they consciously willed to suppress the distress compared with the null state of just attending to negative stimuli. But this distress reduction occurred only in the emotional working memory training group.
No change in neural activity levels was indicated in brain scans as a result of placebo training, but significant increases occurred in the executive control regions of interest as a result of emotional working memory training, irrespective of the level of n-back achievement.
The study also compared emotional responsivity before and after training. Subjects were asked to just pay attention or to pay attention and cognitively suppress their emotional reaction. Subjects rated their emotions on a numerical scale from negative to positive while viewing films that were emotionally neutral (such as weather forecasts) or that were emotionally disturbing (such as war scenes, accidents, etc.). Training caused no change in the group that viewed only neutral images, but in the groups viewing disturbing scenes, training decreased the perceived distress in a group told just to attend the scenes and was even more effective in the group told to suppress emotional reaction.
The emotional working memory training produced benefits that transferred to the emotional response task. Trained subjects not only regulated their emotions better but also developed greater brain-scan activity during the emotional task in the predicted brain regions of interest, the executive control loci. In other words, the training actually changed brain function on a lasting basis. Traditionally, we have always thought that the sole benefit of n-back memory training is to expand the amount of information that can be held in working memory. But now we see that such training can improve our ability to control emotions. Emotional working memory training improves the ability to suppress disturbing emotional responses and does so presumably because the executive control network is more activated. Thus, such training might also enhance many executive control functions, particularly responses to emotionally disturbing circumstances. A new tool for self-control may have been discovered.

Sources:

Banich, M. T., Mackiewicz, K. L., Depue, B. E., Whitmer, A. J., Miller, G. A. , Heller, W. (2009) Cognitive control mechanisms, emotions and memory: a neural perspective with implications for psychopathology. Neurosci. Biobehav. Rev. 33, 613-630.

Beck, A. T. (2008) The evolution of the cognitive model of depression and its neurobiological correlates. Am. J. Psychiatry. 165, 969-977.

Schweizer, S., Grahn, J., Hampshire, A., Mobbs, D., and Dalgleish, T. (2013).  Training the emotional brain: improving affective control through emotional working memory training. J. Neurosci. 33(12), 5301-5311.

Readers of this column can learn more about n-back training and numerous other ways to improve brain function in "Memory Medic's" e-book, Improve Your Memory for a Healthy Brain. For a limited time only, this book is priced at 99 cents, available in all formats from Smashwords.com.

                                                          

Sunday, October 13, 2013

Happy Thoughts Can Make You More Competent

“Life, liberty, and the pursuit of happiness:” some people might argue that the U.S. Constitution endorses hedonism, and indeed many politicians want to ignore or get rid of the Constitution, but not necessarily because of hedonism. We should not be dismissive about encouraging people to pursue happiness. Happiness can be good for your brain. Depression is surely bad for your brain.

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Positive mood states promote more effective thinking and problem solving. A recent scholarly report[1] reviews the literature demonstrating that positive mood broadens the scope of attentiveness, enhances semantic associations over a wide range, improves task shifting, and improves problem-solving capability. The review also documents the changes in brain activation patterns induced by positive mood in subjects while solving problems. Especially important is the dopamine signaling in the prefrontal cortex.

Published studies reveal that a variety of techniques are used to momentarily manipulate mood. These have included making subjects temporarily happy or sad by asking subjects to recall emotionally corresponding past experiences or to view film clips or hear words that trigger happy or sad feelings,

The effect of happiness on broadened attentiveness arises because the brain has better cognitive flexibility and executive control, which in turn makes it easier to be more flexible and creative. Happy problem solvers are better able to select and act upon useful solutions that otherwise never consciously surface. Happiness reduces perseverative tendencies for errant problem-solving strategies. The broadened attentiveness, for example, allows people to attend to more stimuli, both in external visual space and in internal semantic space, which in turn enables more holistic processing. For example, in one cited study, experimenters manipulated subjects’ momentary mood and then measured performance on a task involving matching of visual objects based on their global versus local shapes. Happy moods yielded better global matching.

Other experiments report broader word association performance when subjects are manipulated to be happier. For example, subjects in a neutral mood would typically regard the word “pen” as a writing tool and would associate it with words like pencil or paper. But positive mood subjects would think also of pen as an enclosure and associate it with words like barn or pigs. This effect has been demonstrated with practical effect in physicians, who, when in a happy mood, thought of more disease possibilities in making a differential diagnosis.

The review authors reported their own experiment on beneficial happy mood effects on insightfulness, using a task in which subjects were given three words and asked to think of a fourth word that could be combined into a compound word or phrase. For example, an insightful response to “tooth, potato, and heart” might be “sweet tooth, sweet potato, and sweetheart.” Generating such insight typically requires one to suppress dominant “knee jerk” responses such as associating tooth with pain and recognizing that pain does not fit potato while at the same time becoming capable of switching to non-dominant alternatives.

Other cited experiments showed that happy mood improved performance on “Duncker’s candle task.”  Here, subjects are given a box of tacks, a candle, and a book of matches, and are asked to attach a candle to the wall in a way that will burn without dripping wax on the floor. Subjects in a happy mood were more able to realize that the box could be a platform for the candle when the box is tacked to the wall.  

Such effects of happy moods seem to arise from increased neural activity in the prefrontal cortex and cingulate cortex, areas that numerous prior studies have demonstrated as crucial parts of the brain’s executive control network. Similar effects have been observed in EEG studies. Other research suggests that the happiness effect is mediated by increased release of dopamine in the cortex that serves to up-regulate executive control.

The review authors described a meta-analysis of 49 positive-psychology manipulation studies showing that momentary happiness is readily manipulated by such strategies as deliberate optimistic thinking, increased attention to and memory of happy experiences, practicing mindfulness and acceptance, and increasing socialization. The effect occurs in most normal people and even in people with depression, anxiety, and schizophrenia. Biofeedback training, where subjects monitor their own fMRI scans or EEGs, might be an even more effective way for people to train themselves to be happier.

The main point is that people can be as happy as they choose to be.


For more on how positive mood influences memory ability,
see my new book, Memory Power 101 (http://skyhorsepublishing.com).






[1] Subramaniam, K. and Vinogradov, S. (2013). Improving the neural mechanisms of cognition through the pursuit of happiness. Frontiers in Human Neuroscience. 7 August. Doi: 10.3389/fnhum.2013.00452

Tuesday, June 11, 2013

Working Memory Executive Control

Do you consciously monitor your working memory? That’s the limited-capacity memory you use when looking up a phone number, for example. If you fail to keep the numbers actively in mind while dialing, you may have to look up the number again. In other words, do you check yourself to see if you are still paying attention to what is in your working memory? Is your mind wandering away from what you are trying to hold in working memory? The cure is to deploy your brain’s innate capacity for executive control over working memory.

For more complicated memory chores than dialing a phone number, are you consciously aware of updating what is in your working memory at a given moment with new information? Do you think about being able to recall information you have just received—as when you are reading? Or do you ever willfully suppress what is in your working memory—as for example, expunging an unpleasant thought.

These questions deal with how well you are consciously aware of the likelihood you can recall what you are experiencing. I suspect that most of us exert some conscious executive control over working memory, but not nearly as efficiently as we could or should. Does it matter? Well yes, because controlling what is in your working memory affects the ongoing thought processes that are using the information that is in working memory. Moreover, how well you monitor your working memory affects how well the information registers in your brain and how well it can become consolidated into a more lasting memory.
I explain the consolidation process and ways to enhance it in my book, Memory Power 101.

Executive control of memory is relatively new in memory research, but one group reports studies suggesting that such research will prove fruitful. A year or so ago, this group’s poster presentation at the Society of Neuroscience meeting intrigued me, and I am delighted that the work has now been formally published.

One of their experiments evaluated listeners’ ability to monitor their moment-to-moment working memory storage capacity as new information arrived. As they listened to recorded word lists, experimenters told the subjects to pause the input at the maximum point that would still allow them for perfect real-time memory recall. That is, they pressed a key to pause the input of words in the list at the latest point at which they believe they would have perfect recall. Interestingly, all subjects paused the recording consistent with their known working memory span, as had been determined in pre-experiment testing. In a follow-up experiment, experimenters reduced the sound volume of the word list so that more effort had to be exerted to perform the task. Under these conditions, subjects were much less accurate in matching their listening to their natural working memory capacity and thus their learning was not optimal.

Obviously, such results suggest that making tasks more difficult can degrade thinking and learning. Teachers and professors who speak softly or with foreign accents should take note. Whatever benefit accrues from the challenge to pay better attention under difficult situations is offset by limitations in working memory storage capacity. Examples of degrading influences in addition to sound volume in listening to information include:

Listening is made more difficult by:

·         Extraneous noise
·         Unfamiliar speech accents
·         Speaking too rapidly
·         Speaking too softly
·         Simultaneous presence of visual stimuli that conflict or distract
·         Irritating or distracting mannerisms of the speaker

Reading is made more difficult by:

·         Font and page design selection
·         Convoluted syntax, awkward sentence structure
·         Unfamiliar vocabulary
·         Distracting visuals
·         Wordiness, poor grammar
·         Poor reading technique (tracking with finger movements, random eye fixations, small fixation span (a few letters or one word at a time)

In all situations, an important factor is whether the listener or reader has control over the speed of information presentation. Thinking and learning are compromised if a person has no control over chunking of information input and matching the input to their working memory storage capacity.

Another factor, not considered in this study, is the likelihood that people differ significantly in conscious executive control capability. We know, for example, that some people can hold focus much better than others can, and this certainly affects their ability to optimize working memory storage of information input.

Can working memory executive control be trained? There are already effective training protocols for expanding working memory capacity (as in the number of items you can hold in working memory). I suspect that we will soon see training programs to enhance executive control of working memory.

To summarize, you can optimize thinking and learning by willfully controlling the ease and convenience of information input as well as by how well you have developed a habit of conscious executive control.

Source:

Amichetti, N. M., Stanley, R. S., White, A. G., and Wingfield, A. (2013). Monitoring the capacity of working memory: executive control and effects of listing effort. Mem. Cogn. DOI: 10.3758/s113421-013-0302=0