Tag Archives: brain

Electrical Brain Stimulation Boosts Memory

The technique involves implanting electrodes into the brain: in this case into an area in the limbic system called the hypothalamus, which is thought to control the appetite. When the electrodes were stimulated by electrical impulses the patient began to experience feelings of deja vu.

He then had a sudden perception of being in a park with friends. He felt younger, thought he was around 20-years-old, and his girlfriend of the time was there. He was an observer, and saw the scene in colour. As the intensity of the stimulation increased, details in the scene became more vivid.
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The results suggest it might be possible to use deep brain stimulation directly to boost memory. “We hopefully have found a circuit in the brain which can be modulated by stimulation, and which might provide benefit to patients with memory disorders,” said Professor Lozano. He is now leading a pilot study into whether deep brain stimulation can help people with early Alzheimer’s disease. They are initially testing six patients.

Mapping Where Brains Store Similar Information

CMU finds human brains similarly organized

Based on how one person thinks about a hammer, a computer can identify when another person also is thinking about a hammer. It also can differentiate between items in the same category of tools, be it a hammer or screwdriver.
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The study makes two important scientific advances: “[T]here is an identifiable neural pattern associated with perception and contemplation of individual objects, and that part of the pattern is shared” by people.

The study reveals that patterns of thought extend into different regions of the brain, reflecting its complexity. It proves that a simple image can invoke thoughts in various regions of the brain, including how to use the object and experiences one has had with the object.

The study also helps to explain how the brain organizes thoughts, and the commonality of that process. “I want a complete mapping of brain states and thoughts,” Dr. Just said. “We’re taking tiny baby steps, but anything we can think about is represented in the brain.”

Brain Development

Making the Mind, Why we’ve misunderstood the nature-nuture debate by Gary Marcus

The mapping between genes and behavior is made even more complex by the fact that few if any neural circuits operate entirely autonomously. Except perhaps in the case of reflexes, most behaviors are the product of multiple interacting systems. In a complex animal like a mammal or a bird, virtually every action depends on a coming together of systems for perception, attention, motivation, and so forth. Whether or not a pigeon pecks a lever to get a pellet depends on whether it is hungry, whether it is tired, whether there is anything else more interesting around, and so forth. Furthermore, even within a single system, genes rarely participate directly “on-line,” in part because they are just too slow. Genes do seem to play an active, major role in “off-line” processing, such as consolidation of long-term memory—which can even happen during sleep—but when it comes to rapid on-line decision-making, genes, which work on a time scale of seconds or minutes, turn over the reins to neurons, which act on a scale of hundredths of a second. The chief contribution of genes comes in advance, in laying down and adjusting neural circuitry, not in the moment-by-moment running of the nervous system. Genes build neural structures—not behavior.

An interesting read on brain development. This is another topic I find very interesting.

Why do We Sleep?

Study puts us one step closer to understanding the purpose of sleep:

Sleep remains one of the big mysteries in biology. All animals sleep, and people who are deprived of sleep suffer physically, emotionally and intellectually. But nobody knows how sleep restores the brain.
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Although an electronic power-napper sounds like a product whose time has come, Tononi is chasing a larger quarry: learning why sleep is necessary in the first place. If all animals sleep, he says, it must play a critical role in survival, but that role remains elusive.

Based on the fact that sleep seems to “consolidate” memories, many neuroscientists believe that sleeping lets us rehearse the day’s events.

Tononi agrees that sleep improves memory, but he thinks this happens through a different process, one that involves a reduction in brain overload. During sleep, he suggests, the synapses (connections between nerve cells) that were formed by the day’s learning can relax a little.

How The Brain Rewires Itself

How The Brain Rewires Itself:

The finding was in line with a growing number of discoveries at the time showing that greater use of a particular muscle causes the brain to devote more cortical real estate to it. But Pascual-Leone did not stop there. He extended the experiment by having another group of volunteers merely think about practicing the piano exercise. They played the simple piece of music in their head, holding their hands still while imagining how they would move their fingers. Then they too sat beneath the TMS coil.

When the scientists compared the TMS data on the two groups–those who actually tickled the ivories and those who only imagined doing so–they glimpsed a revolutionary idea about the brain: the ability of mere thought to alter the physical structure and function of our gray matter.