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The Human Brain - Stress

The Human Brain - Stress
Chronic over-secretion of stress hormones adversely affects brain function, especially memory. Too much cortisol can prevent the brain from laying down a new memory, or from accessing already existing memories. The renowned brain researcher, Robert M. During a perceived threat, the adrenal glands immediately release adrenalin. topics

Eye movements reveal unconscious memory retrieval : Neurophilosophy THIS short film clip shows two images of the same scene. Watch it carefully, and see if you can spot the subtle differences between them. As you watch, your eyes will dart back and forth across the images, so that you can perceive the most important features. And even though you might not be consciously aware of the differences, your brain will have picked up on them. However, it was unclear whether relational memory retrieval involved the same neural substrates as retrieval of other, more familiar types of memory, such as your recollection of what you had for breakfast this morning, or what you did last weekend. That the hippocampus is critical for memory formation was first established by the pioneering neuropsychologist Brenda Milner in the 1950s. Deborah Hannula and Charan Ranganath therefore set out to investigate whether the eye movements associated with relational memory would be correlated with hippocampal activity. Analysis of the fMRI data confirmed this. More on memory:

Neurostress: How Stress May Fuel Neurodegenerative Diseases In 2007, James Watson eyed his genome for the very first time. Through more than 50 years of scientific and technological advancement, Watson saw the chemical structure he once helped unravel now fused into a personal genetic landscape laid out before him. Yet there was a small stretch of nucleic acids on chromosome 19 that he preferred to leave uncovered, a region that coded the apolipoprotein E gene. APOE, as it’s called, has been a telling genetic landmark of Alzheimer’s risk, strongly correlated to the disease since the early 90s. Watson’s grandmother suffered from Alzheimer’s, and without any reasonable treatments or suitable preventive strategies, the father of DNA decided the information was too volatile, its revelation creating more potential harm than good. Watson’s apprehension was warranted. When studying identical twins, researchers can sift through such questions, says Plassman. More or less, all of the primates raised in normal size cages had the same amount of plaque.

Bodily motions influence memory and emotions : Neurophilosophy WHEN talking about our feelings, we often use expressions that link emotions with movements or positions in space. If, for example, one receives good news, they might say that their “spirit soared”, or that they are feeling “on top of the world”. Conversely, negative emotions are associated with downward movements and positions – somebody who is sad is often said to be “down in the dumps”, or feeling “low”. According to a new study published in this month’s issue of the journal Cognition, expressions such as these are not merely metaphorical. The research provides evidence of a causal link between motion and emotion, by showing that bodily movements influence the recollection of emotional memories, as well as the speed with which they are recalled. For their latest study, Casasanto and Dijkstra recruited 24 undergraduates and asked them to sit at a desk in front of a laptop computer. Related:

Sexual orientation – wired that way In a recent post, I presented the evidence that sexual preference is strongly influenced by genetic variation. Here, I discuss the neurobiological evidence that shows that the brains of homosexual men and women are wired differently from those of their heterosexual counterparts. First, we must consider the differences between the brains of heterosexual males and females. These differences are extensive and arise mainly due to the influence of testosterone during a critical period of early development (see Wired for Sex). They include, not surprisingly, differences in the number of neurons in specific regions of the brain involved in reproductive or sexual behaviours as well as differences in the number of nerve fibres connecting these areas. It should be emphasized that all of these differences are apparent only in group averages and there is very substantial overlap in the distributions of the measures of different brain regions in males and females. Savic I, & Lindström P (2008).

The woman who knows no fear : Neurophilosophy SM has been studied extensively during the past two decades. Early investigations showed that her non-verbal visual memory was signficantly impaired but that otherwise she had an IQ in the low-average range. She also displayed inappropriate social behaviours, quickly becoming friendly with the experimenters and making sexual remarks, due to disturbed executive control. None of these previous studies assessed her experience of fear, however. Next, the researchers took SM on a Halloween visit to Waverly Hills Sanatorium in Louisville, Kentucky, which features people dressed as monsters, murderers and ghosts and is reported to be “one of the most haunted places in the world”. Finally, they showed her scenes from scary movies, such as The Ring, The Blair Witch Project and The Shining, interspersed with clips that induce disgust, anger, surprise, and happiness. SM reports having experienced fear as a young child.

The depression map: genes, culture, serotonin, and a side of pathogens | Wired Science  Maps can tell surprising stories. About a year ago, Northwestern University psychologist Joan Chiao pondered a set of global maps that confounded conventional notions of what depression is, why we get it, and how genes — the so-called “depression gene” in particular — interact with environment and culture. So she gathered it. Chiao and one of her grad students, Katherine Blizinsky, found all the papers they could that studied serotonin or depression in East Asian populations. These papers, along with similar studies in other countries and some World Health Organization data on mental health, painted a pretty good picture of short-SERT variant and depression rates not just in North American and Europe, but in East Asia. A pretty good picture — but seemingly twisted in the middle. You can see it in the maps. Fig 1. Fig 2. You can chart the data in other ways too, and it still looks weird. Squaring two maps with a third As Chiao recognized, several possibilities offered themselves.

ADHD in Adults - Symptoms, Causes, Types, Treatments, and More Why do I need to register or sign in for WebMD to save? We will provide you with a dropdown of all your saved articles when you are registered and signed in. What is Attention Deficit Hyperactivity Disorder (ADHD)? Attention deficit hyperactivity disorder (ADHD) is one of the most well-recognized childhood developmental problems. This condition is characterized by inattention, hyperactivity and impulsiveness. Recommended Related to ADD-ADHD ADHD and Risky Behavior in Adults When Amanda, 30, was diagnosed with ADHD five years ago, she began to understand the risk-taking that had marked her teens and twenties: the drug abuse, binge drinking, and casual sex with numerous men who had flirted with her in bars. Read the ADHD and Risky Behavior in Adults article > > ADHD in Adults Adults with ADHD may have difficulty following directions, remembering information, concentrating, organizing tasks, or completing work within time limits. Adult ADHD Statistics Common Behaviors and Problems of Adult ADHD

A stranger in half your body An amazing study has just been published online in Consciousness and Cognition about a patient with epilepsy who felt the left half of his body was being “invaded by a stranger” when he had a seizure. As a result, he felt he existed in one side of his body only. The research is from the same Swiss team who made headlines with their study that used virtual reality to make participants feel they were in someone else’s body, and one where brain stimulation triggered the sensation of having an offset ‘shadow body’ in patients undergoing neurosurgery. The researchers suggest that having an integrated sense of our own bodies involves three types of perception: self-location – the area where we experience the self to be located; first-person perspective – the perceived centre of the conscious experience; and self-identification – the degree to which we identify sensations with our own bodies. Patient 1 is a 55 year old, left-handed male patient suffering from epilepsy since the age of 14 years.

Mini-strokes leave 'hidden' brain damage Each year, approximately 150,000 Canadians have a transient ischemic attack (TIA), sometimes known as a mini-stroke. New research published January 28 in Stroke, the journal of the American Heart Association shows these attacks may not be transient at all. They in fact create lasting damage to the brain. The stroke research team, led by Dr. "What we found has never been seen before," says Dr. In the TIA group, brain cells on the affected side of the brain showed changes in their excitability -- making it harder for both excitatory and inhibitory neurons to respond as compared to the undamaged side and to a group of people with healthy brains. A transient ischemic attack is characterized as a brief episode of blood loss to the brain, creating symptoms such as numbness or tingling, temporary loss of vision, difficulty speaking, or weakness on one side of the body. "These findings are very important," says Dr.

Music, Mind, and Meaning This is a revised version of AI Memo No. 616, MIT Artificial Intelligence Laboratory. An earlier published version appeared in Music, Mind, and Brain: The Neuropsychology of Music (Manfred Clynes, ed.) Plenum, New York, 1981 Why Do We Like Music? Why do we like music? Have we the tools for such work? Certainly we know a bit about the obvious processes of reason–the ways we organize and represent ideas we get. The old distinctions among emotion, reason, and aesthetics are like the earth, air, and fire of an ancient alchemy. Much of what we now know of the mind emerged in this century from other subjects once considered just as personal and inaccessible but which were explored, for example, by Freud in his work on adults' dreams and jokes, and by Piaget in his work on children's thought and play. Why do we like music? I feel that music theory has gotten stuck by trying too long to find universals. Sonata as Teaching Machine Compare a sonata to a teacher. Cadence. What Use Is Music?

Our brains are wired so we can better hear ourselves speak, new study shows Like the mute button on the TV remote control, our brains filter out unwanted noise so we can focus on what we’re listening to. But when it comes to following our own speech, a new brain study from the University of California, Berkeley, shows that instead of one homogenous mute button, we have a network of volume settings that can selectively silence and amplify the sounds we make and hear. Activity in the auditory cortex when we speak and listen is amplified in some regions of the brain and muted in others. Neuroscientists from UC Berkeley, UCSF and Johns Hopkins University tracked the electrical signals emitted from the brains of hospitalized epilepsy patients. Their findings, published today (Dec. 8, 2010) in the Journal of Neuroscience, offer new clues about how we hear ourselves above the noise of our surroundings and monitor what we say. The auditory cortex is a region of the brain’s temporal lobe that deals with sound.