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How Our Brains Make Memories Sitting at a sidewalk café in Montreal on a sunny morning, Karim Nader recalls the day eight years earlier when two planes slammed into the twin towers of the World Trade Center. He lights a cigarette and waves his hands in the air to sketch the scene. At the time of the attack, Nader was a postdoctoral researcher at New York University. He flipped the radio on while getting ready to go to work and heard the banter of the morning disc jockeys turn panicky as they related the events unfolding in Lower Manhattan. Nader ran to the roof of his apartment building, where he had a view of the towers less than two miles away. He stood there, stunned, as they burned and fell, thinking to himself, “No way, man. In the following days, Nader recalls, he passed through subway stations where walls were covered with notes and photographs left by people searching desperately for missing loved ones. Nader believes he may have an explanation for such quirks of memory.

Magnetic manipulation of the sense of morality : Neurophilosophy WHEN making moral judgements, we rely on our ability to make inferences about the beliefs and intentions of others. With this so-called “theory of mind”, we can meaningfully interpret their behaviour, and decide whether it is right or wrong. The legal system also places great emphasis on one’s intentions: a “guilty act” only produces criminal liability when it is proven to have been performed in combination with a “guilty mind”, and this, too, depends on the ability to make reasoned moral judgements. MIT researchers now show that this moral compass can be very easily skewed. Liane Lee Young of MIT’s Department of Brain and Cognitive Science and her colleagues asked participants to make moral judgements about different variations of a number of scenarios. These scenarios differ in the beliefs underlying Grace’s actions and in their outcome. Whether or not these findings extend to real world judgements remains to be seen. Young, L., et al. (2010). Saxe, R. & Kanwisher, N. (2003).

Increased Interstitial White Matter Neuron Density in the Dorsolateral Prefrontal Cortex of People with Schizophrenia To view the full text, please login as a subscribed user or purchase a subscription. Click here to view the full text on ScienceDirect. Figure 1 Neuronal nuclear antigen (NeuN)–positive neurons (A) below grey matter (grey matter/white matter border represented by dotted line). In superficial white matter from (B) control and (C) schizophrenia subjects. Figure 2 Density of neuronal nuclear antigen + immunopositive interstitial white matter (neurons/mm2) in (A) superficial white matter and (B) deep white matter in control subjects (squares) and schizophrenic cases (triangles). Figure 3 Superficial neuronal nuclear antigen immunopositive interstitial white matter neuron (IWMN) density (neurons/mm2) negatively correlates with gray matter somatostatin (SST) expression in control subjects and schizophrenia cases (control, squares; schizophrenia, triangles). qPCR, quantitative polymerase chain reaction. Figure 4 Figure 5 Figure 6 Somatostatin (SST) and neuropeptide Y (NPY) expression in IWMN cells.

Chapter 12: Attention and Consciousness Attention involves top-down (voluntary) goal-directed processes and bottom-up (reflexive), stimulus-driven mechanisms. They influence the way information is processed in the brain and can occur early during sensory processing. Balint's syndrome is a visual attention and awareness deficit. Herman von Helmholt He did an experiment that looked at covert attention. E.C. He looked at the cocktail effect, which is the idea that in a noisy environment people cal focus on a single conversation. Donald Broadbent He came up with the model of selective attention, which states that there is a gating mechanism that determines what information is passed on for higher analysis. Michael Posner He came up with the spatial cuing paradigm. Reflexive Attention reflexive cuing: attention to an external stimuli. Anne Tresiman She did an experiment that focused on the visual search paradigm. Attention to Features and Objects. Neurophysiology Steven Hillyard looked and auditory selective attention. Neuroimaging

Autism and Neuropsychology, by Marisa Marzillo Autism is a lifelong disorder that has become the discussion of many media outlets; it is a disorder that causes abnormal neurological development. It seems that lately autism prevalence is increasing, which is causing a demand for professionals to investigate on what causes autism. Autism disorder is characterized by different behavior including social impairments, difficulty in communication, and restrictive patterns of behavior. Individuals living with autism don’t have a lower IQ than most people, but it is common that they have weak social interaction. What I find interesting about autism is that there it solely diagnosed by behavioral activity. In an article Elizabeth Lynch (2010) described autism as a “lifelong developmental disability that affects the way an individual relates to others. One explanation for the link between autism and brain development is mirror neurons. A theory that I found interesting was one that pointed out the autism is more common in males. References

Phantoms in the Brain The writings of Oliver Sacks and others have shown us that we can learn much about ourselves by looking closely at the deficits shown by people with neurological problems. V.S. Ramachandran has seen countless patients suffering from anosognosia, phantom limb pain, blindsight, and other disorders, and he brings a remarkable mixture of clinical intuition and research savvy to bear on their problems. He is one of the few scientists who are able and willing to explore the personal, subjective ramifications of his work; he rehumanizes an often too-sterile field and captures the spirit of wonder so essential for true discovery. Phantoms in the Brain is equal parts medical mystery, scientific adventure, and philosophical speculation. Watch the full documentary now (playlist - 1 hour, 39 minutes)

How Alcohol Affects the Brain General Effects of Alcohol on the Brain Alcohol can affect several parts of the brain, but in general, alcohol contracts brain tissue and depresses the central nervous system. Also, alcohol destroys brain cells and unlike many other types of cells in the body, brain cells do not regenerate. Excessive drinking over a prolonged period of time can cause serious problems with cognition and memory. When alcohol reaches the brain, it interferes with communication between nerve cells, by interacting with the receptors on some cells. The alcohol suppresses excitatory nerve pathway activity and increases inhibitory nerve pathway activity. Chemical Effects of Alcohol on the Brain To understand how alcohol interferes with brain function, it is necessary to know a little bit about normal brain function. The gap between cells where neurotransmitters are active is called the synapse. When alcohol is introduced to the synapse, the normal neurotransmission may be affected. The cerebral cortex and alcohol

Neuroscientists reveal magicians' secrets - Technology & science - Science - LiveScience NEW YORK — There is a place for magic in science. Five years ago, on a trip to Las Vegas, neuroscientists Stephen Macknik and Susana Martinez-Conde realized that a partnership was in order with a profession that has an older and more intuitive understanding of how the human brain works. Magicians, it seems, have an advantage over neuroscientists. "Scientists have only studied cognitive illusions for a few decades. Magicians have studied them for hundreds, if not thousands, of years," Martinez-Conde told the audience during a recent presentation here at the New York Academy of Sciences. [ Video: Your Brain on Magic ] She and Macknik, her husband, use illusions as a tool to study how the brain works. After their epiphany in Las Vegas, where they were preparing for a conference on consciousness, the duo, who both direct laboratories at the Barrow Neurological Institute in Arizona, teamed up with magicians to learn just how they harness the foibles of our brains. Most popular

Subliminal Stimuli Explained Subliminal Articles There is a lot of misunderstanding about the term subliminal and how subliminal messages, especially those found a subliminal CDs, work. Subliminal messages are not just verbal commands. They can take the form of a single hidden word, entire sentences or even images which elicit an emotional response at a subconscious level. Therefore most subliminal messages, in popular use, are better referred to as "subliminal stimuli". The word "subliminal" is used to refer to anything that is registered by the brain but is only offered to the senses below the threshold of conscious perception. Subliminal stimuli refers to anything that stimulations the brain and senses at a subliminal level. For example an image may be shown so quickly to an individual that all he or she is consciously aware of is a flash of light or imperceptible image. Likewise a verbal message may also be hidden, or "masked", behind other sounds so that the words being spoken are imperceptible. Lecture 3 The Left Hemisphere From: Neuropsychiatry, Neuropsychology, Clinical Neuroscience by Rhawn Joseph, Ph.D. (Academic Press, New York, 2000) Language, Consciousness, Handedness, Aphasia, Apraxia, Alexia Agraphia, Depression, Schizophrenia, Ego-Centric Speech & The Origin of Thought Handeded and Hemispheric Functional Laterality The left half of the brain controls the right hand. Among 80-90% of right handers, and over 50-80% of those who are left handed, the left cerebral hemisphere provides the neural foundation and mediates most aspects of expressive and receptive linguistic functioning (Frost et al., 1999; Pujol, et al., 1999). As demonstrated with functional imaging and blood flow studies, when reading, speaking, and naming, the left hemisphere becomes highly active (Buchel et al., 1998; Evers et al., 1999; Frost et al., 1999; Peterson et al., 1988, 1990; Price, 1997; Pujol, et al., 1999). The Language Axis "Gnosis" means to "know" Agnosia means, not to know. It has now been well established that the right cerebral hemisphere is dominant over the left in regard to the perception, expression and mediation of almost all aspects of social and emotional functioning (e.g. Borod, 1992; Cancelliere & Kertesz, 1990; Freeman & Traugott, 1993; Heilman & Bowers 1995; Heilman et al. 1985; Joseph 1988a; Tucker & Frederick, 1989; see below), including the recall of emotional memories (Cimino et al., 1991; Rauch et al., 1996; Shin et al., 1997). This emotional dominance extends to bilateral control over the autonomic nervous system, including heart rate, blood pressure regulation, galvanic skin conductance and the secretion of cortisol in emotionally upsetting or exciting situations (Rosen et al. 1982; Wittling, 1990; Wittling & Pfluger, 1990; Yamour et al. 1980; Zamarini et al. 1990). However, this dominance does not appear to extend to the immune system (Meador et al., 1999). Aphasia & Depression Wernicke's Area When hallucinations follow depth electrode or cortical stimulation, much of the material experienced is very dream-like (Gloor 1990, 1992; Halgren et al., 1978; Malh et al., 1964; Penfield & Perot 1963) and consists of recent perceptions, ideas, feelings, and other emotions which are similarly illusionary and dream-like. Indeed, the right amygdala, hippocampus, and the right hemisphere in general (Broughton, 1982; Goldstein et al., 1972; Hodoba, 1986; Humphrey & Zangwill, 1961; Kerr & Foulkes, 1978; Meyer et al. 1987) also appear to be involved in the production of deam imagery as well as REM sleep (chapter 10). For example stimulation of the amygdala triggers and increases ponto-geniculo-occipital paradoxical activity during sleep (Calvo, et al. 1987), which in turn is associated with REM and dreaming. The Right Hemisphere & Dreams. Forgotten Dreams. Most individuals, however, have difficulty recalling their dreams.

The Dark Side of Oxytocin, the Hormone of Love - Ethnocentrism Yes, you knew there had to be a catch. As oxytocin comes into sharper focus, its social radius of action turns out to have definite limits. The love and trust it promotes are not toward the world in general, just toward a person’s in-group. Oxytocin turns out to be the hormone of the clan, not of universal brotherhood. A principal author of the new take on oxytocin is Carsten K. In a report published last year in Science, based on experiments in which subjects distributed money, he and colleagues showed that doses of oxytocin made people more likely to favor the in-group at the expense of an out-group. These nationalities were chosen because of a 2005 poll that showed that 51 percent of Dutch citizens held unfavorable opinions about Muslims, and other surveys that Germans, although seen by the Dutch as less threatening, were nevertheless regarded as “aggressive, arrogant and cold.” Well-socialized Dutch students might be unlikely to say anything derogatory about other groups. In Dr.

Unraveling the mystery of why we give, or don't By Judy Keen, USA TODAY SOUTH BEND, Ind. — Generous impulses often are described in fundraising appeals, conversation and greeting cards as coming "from the heart." In fact, the origins of giving probably are deep in the brain's circuitry. Exactly how the complicated workings of the brain stimulate or suppress giving and how families, co-workers and values affect generosity remain a mystery despite years of study. With a $5 million grant from the John Templeton Foundation, Notre Dame created the Science of Generosity Initiative in 2009. Project director Christian Smith, a Notre Dame sociology professor, hopes to unravel the physiological and behavioral mechanisms that make people generous — or not: Why do some people give blood? The explanations, he says, will provide insights into "the cogs and wheels that form people's thinking and desires: feelings, relationships, social networks." Feeling the 'warm glow' There are some well-established theories about generosity. A link to parenting?