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what leads us to make a choice within ourself,who brings out the word choice?
asked in Teacher Training colleges

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Decision-making is such a seamless brain process that we’re usually unaware of it — until our choice results in unexpected consequences. Then we may look back and wonder, “Why did I choose that option?” In recent years, neuroscientists have begun to decode the decision-making process. What they’re learning is shedding light not only on how the healthy brain performs complex mental functions, but also on how disorders, such as stroke or drug abuse, affect the process.

Researchers can study decision-making in animals. As monkeys decide which direction a moving target is headed, researchers record the activity in brain cells called neurons. These studies have helped to reveal the basis for how animals and humans make everyday decisions.
Modified and reprinted by permission from Macmillan Publishers, Ltd: Nature Neuroscience, 9(7)861-863, 2006.

Decisions. Decisions. Each day you make thousands of them. Many — what to eat for breakfast or what to wear to a friend’s party — have few, if any, long-lasting consequences. Others — whether to stay in school or look for work — can have a huge impact on the direction of your life.

Neuroscientists have long questioned how the human brain makes decisions, from where to gaze to complex moral judgments. Research suggests that the brain considers various sources of information before making a decision. But how does it do this? And why does the process sometimes go awry, causing us to make impulsive, indecisive, and confused decisions — the kinds that can lead to risky and potentially dangerous behaviors?

Thanks to advances in technology, researchers are beginning to unravel the mysterious processes by which humans make decisions. New research is helping scientists develop:

    A deeper understanding of how the human brain reasons, plans, and solves problems.
    Greater insight into how sleep deprivation, drug abuse, neurological disorders, and other factors affect the decision-making process, suggesting new behavioral and therapeutic approaches to improve health.

Our brains appear wired in ways that enable us, often unconsciously, to make the best decisions possible with the information we’re given. In simplest terms, the process is organized like a court trial. Sights, sounds, and other sensory evidence are entered and registered in sensory circuits in the brain. Other brain cells act as the brain’s “jury,” compiling and weighing each piece of evidence. When the accumulated evidence reaches a critical threshold, a judgment — a decision — is made.

Where these judgments are made in the brain differs depending on the type of decision. For example, by studying stroke patients, researchers found that different parts of the frontal lobe, an area involved in planning and reasoning, are important in abstract and concrete decisions. People with stroke damage in the front of this brain region had trouble with abstract decisions, such as deciding to wash dishes, whereas people with damage in the back had trouble with concrete decisions, like the selection of physical movements during dishwashing. Other researchers studying monkeys found that decisions based on visual information rely on the parietal lobe, which integrates evidence supplied by the senses.

In these different brain regions, research shows that decisions result from rapid and complex probability calculations in brain cells called neurons. In one study, monkeys played a video game that required them to determine which of two possible directions a moving display of random dots was headed. If a monkey guessed the direction correctly — by gazing at one of the two targets — it received a reward. As the monkey made its decisions, researchers recorded the electrical activity of neurons in the parietal lobe, and found that it closely correlated with the monkey’s decisions. In fact, the researchers could predict the monkey’s choices based solely on brain cell activity.

Neuronal activity in the parietal lobe not only accurately predicted the monkey’s choice, but also the certainty with which the decision was made. In addition to trying to select the correct target for a big reward, the monkeys were able to choose a fixed target, which guaranteed a smaller, less desirable reward. When the monkey lacked confidence in its target selection, it chose the sure bet, and the brain cell activity in its parietal lobe changed, suggesting these cells also indicate the monkey’s confidence level.

What happens when we change our minds? Scientists have found that when a decision goes wrong and things turn out differently than expected, the orbitofrontal cortex, located at the front of the brain behind the eyes, responds to the mistake and helps us alter our behavior. Interestingly, researchers have found that cocaine addicts, who are often unable to weigh the rewards of drug use against its costs, show impairments of the orbitofrontal cortex.

In addition to drug abuse, other factors can cause the decision-making mechanisms in the brain to go awry, leading to risky or even dangerous behaviors. One study found, for example, that losing a full night’s sleep caused people to adopt much riskier-than-normal gambling strategies.

All these findings indicate how much researchers have learned and how much is yet to be learned about how and why we make decisions, one of our most complex and essential human behaviors.
0 votes
Most likely, you take decision making somewhat for granted. Maybe not big, life-changing decision making, the sort where you make columns of pros and cons and sit down with friends and family for deep meaningful conversations, but decisions like, Do I want to listen to a tape of some band or do I want to listen to NPR on this drive to the grocery store, or, Wait, do I need to go to the grocery store at all or maybe just Rite Aid, or maybe Melcom is a little closer. It might be easier to just take the highway to Shoprite but fuck Shoprite. You probably don’t spend 20 percent of your day stumped over little things that don’t actually matter in the grand scheme—you just do them.

Making decisions—choosing—is one of the most crucial tasks your brain is responsible for, and certainly one of its most easily taken for granted. Inability to make decisions or having an extremely difficult time making them is a symptom of some mental illnesses—depression and schizophrenia, especially—that doesn’t get due credit for its debilitating effects. You need to be able to choose. Otherwise, life is a neverending series of roadblocks always compounding and always feeding back into the initial illness. Limbo is the inability to choose, and it traces back to a small and ill-understood part of the brain called the lateral habenula, the decision-making role of which is described in a paper out yesterday in Nature Neuroscience.

The University of British Columbia's Stan Floresco, the lead author of the paper, explained your brain's decision-making process in an interview on Sunday. "Although we still have a lot to figure out about the neural circuits underlying different types of decision making," he said, "one way you can look at it is that there are numerous brain regions, many of them in the frontal lobes, that use different types of information—your memories, your individual personality and preference, your current motivations etc—to help make value judgments about different courses of action.

"Different brain regions may be nudging you to go in one direction or another," Floresco said. "I like to use the analogy that there are battles going on in your brain pushing you one way or another. What our results suggest is that this nucleus, the lateral habenula, helps this circuitry reach a definitive decision and/or helps you implement it once there is an apparent 'winner' in this battle."
The lateral habenula doesn’t give us good decision making ability; it gives us the ability to make decisions at all. This revelation comes from rats set up in an elaborate cost-reward scheme. Basically, they were offered choices between consistent small rewards and sporadic larger rewards: some food all of the time or more food just sometimes. With their lateral habenulas turned on, the rats tended to choose the less risky option, making the smart or good decision. Earlier studies have suggested that, with this brain region turned off, the rats would make crappy, riskier decisions. That wasn't the case in the new study.

"The general impression that was emerging in the field was that this part of the brain was a sort of aversion or 'anti-reward' center," Floresco said. "It would signal when bad things happened or were about to happen.  While this is partially true, our results suggests that its function is a bit broader than that. Rather than just signaling what is bad in your environment, it also helps you figure out what is good, especially when comparing between two different types of rewards. So, rather than being an 'anti-reward' center, our findings suggest it’s more of a comparator or preference center, that evaluates good and bad things in your environment and helps you choose a course of action that you may think is better for you."

The rats with inactive lateral habenulas just didn’t decide at all—or, rather, they didn’t demonstrate any decision-making ability. In rat-food-scheme terms, they chose both options equally. This finding has potential implications for treating mental illness.

"Although this is still very speculative, what may be going on [in depression] is that when the habenula is inactivated, it pushes patients towards a more ambivalent emotional state (not bad, but not good either).  So if a patient feels very bad in a depressed state, moving to 'neutral' state would actually present as a clinical improvement in symptoms."

The research raises the question of whether the lateral habenulas might represent a link between schizophrenia and depression. The short answer is not yet. Some literature points to the disorders sharing some of the same brain circuitry, but the problems with that circuitry may be different between the two. For now, the lateral habenulas may represent a potential target for deep brain stimulation therapy for depression. In the meantime: just flip a coin already.