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Hippocampus

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Declarative Memory. A review on the neural bases of episodic odor memory: from laboratory-based to autobiographical approaches. Introduction.

Conscious and controlled recollection of specific and complex events from the past. Three dimensionality of episodic memory: What happened, Where and When? A module of tightly-connected brain regions (hippocampus, caudate nucleus, anterior cingulate and medial temporal gyrus) is specifically involved when odors are accurately recognized. The personal significance of the cue item generates the engagement of semantic processes, as highlighted by the role of the inferior frontal gyrus, and of emotional and visual imagery processes reflecting the vividness of the recalled memories. Studying autobiographical memories also enables addressing consolidation process over time and suggests a continuous engagement of the hippocampus whatever the age of the memory. – weihler
A review on the neural bases of episodic odor memory: from laboratory-based to autobiographical approaches

Mobile Learning: Structures, Agency, Practices - Norbert Pachler, Ben Bachmair, John Cook. Numismatics, 50 Pfennig, Bank Deutscher Länder, 1950 G. Das Postsparbuch. Reiseberichte: Sommer 1959 - Radtour zum BODENSEE und 49 Jahre danach! INSPIRATIONS & UPDATES. Side Walks is on it's way!

Loving this one. She is providing individual methods to discover places and creating events. For example, write your name on the city map of the where you are, walk along the streets. Today watch and compare shop signs, doors, pavements or whatever, focus on colors. Draw images or take photographs of your coffee cups, chairs, tables or something else. Collect sugar paper. What music are they playing at the moment? Ask and talk to those people then to other ones. Document it in the book. What to do next. Also a good inspiration to develop own ideas and strategies. – weihler

For those of you as excited as I was to get my hands on Side Walks, rest assured it is on it's way.

INSPIRATIONS & UPDATES

I got an advanced copy this morning and started writing in it within the hour. Chock-full of illustrations this guided journal leads you to discover the hidden details of your city. Spatial navigational strategies correlate with gray matter in the hippocampus of healthy older adults tested in a virtual maze.

There was no correlation between performance on Stage 2 and age, years of education or sex. Performance on Stage 2 of CSDLT positively correlated with gray matter in the right Hippocampus, suggesting that healthy older adults using space strategies having more gray matter in right Hippocampus. No areas in the brain including Caudate were found to correlate negatively with performance on Stage 2. Number of trials did not correlate with with gray matter in Hippocampus or Caudate. Regress analysis showed network of regions linked to the Hippocampus co-vaying with peak voxel in right Hippocampus: contralateral Hippocampus, the right Orbitofrontal Cortex, bilateral Amygdala and bilateral parahippocampal cortex. Summary: Spontanous use of space strategy positively correlates with gray matter in Hippocampus, the use of response strategy negatively. – weihler
It has been suggested, that OFC in rodents is involved in spacial memory and reward expectancy. Parahippocampal cortex is known to be involved in navigation, scene processing and spacial learning. Amygdala is associated with place preference learning, when associated with reward. Previous studies found correlation between RAVLT and volume of left hippocampus, not found here, suggesting spacial memory strategies are more sensitive to structural differences of Hippocampus than standard neuropsychological tests. Prospective study showed, that deficits in spacial memory preceded conversion to dementia by three years. Verbal and working memory deficits were detected only one year before dementia diagnosis. Future studies will be needed to examine wheather an intervention method focussing on spatial memory can increase gray matter in Hippocampus and associated regions. Promoting those strategies could be a route for intervention methods and have protective effects against cognitive decline. – weihler

Cache Cab: Taxi Drivers' Brains Grow to Navigate London's Streets. Manhattan's midtown streets are arranged in a user-friendly grid.

Cache Cab: Taxi Drivers' Brains Grow to Navigate London's Streets

Way The Brain Makes Mental Maps discovered. How The Brain Perceives Direction And Location. Brain time. temporal and feature binding. [DAVID M.

The days of thinking of time as a river, evenly flowing, always advancing, are over. Because different types of sensory information (hearing, seeing, touch, and so on) are processed at different speeds by different neural architectures, your brain faces an enormous challenge: what is the best story that can be constructed about the outside world? We all know about optical illusions, in which things appear different from how they really are; less well known is the world of temporal illusions. The visual brain wants to get events correct timewise, it may have only one choice: wait for the slowest information to arrive. This hypothesis,that the system waits to collect information over the window of time during which it streams in, applies not only to vision but to all the other senses. It may be that a unified polysensory perception of the world has to wait for the slowest overall information. The recalibration of subjective timing is critical to solving the problem of causality. – weihler

EAGLEMAN:] At some point, the Mongol military leader Kublai Khan (1215–94) realized that his empire had grown so vast that he would never be able to see what it contained.

brain time. temporal and feature binding

Each Time You Recall An Event, Your Brain Distorts It. Presynaptic Mechanisms of Synaptic Plasticity. Since its discovery in 1973, synaptic plasticity has garnered the attention and imagination of neuroscientists as a potential cellular basis of learning, memory and development.

Presynaptic Mechanisms of Synaptic Plasticity

As a result, the intense study devoted to the prototypic CA1 long-term potentiation (LTP) in the hippocampus has generated an unparalleled amount of knowledge and made it our best understood model of activity-dependent plasticity in the brain (see here for a discussion of the postsynaptic mechanisms of synaptic plasticity). Thus, it comes as a surprise that controversy still divides the field as to whether presynaptic changes are also involved in its induction and expression. Long Term Potentation. Even though the neurons of the hippocampus may seem like just a transit point in the establishment of long-term memory, they actually display a great deal of plasticity.

Long Term Potentation

This plasticity is manifested chiefly through the phenomenon of long-term potentiation (LTP), which was discovered in the hippocampus in 1973 but has subsequently been demonstrated in many regions of the cortex. The most interesting characteristic of LTP is that it can cause the long-term strengthening of the synapses between two neurons that are activated simultaneously. Learning requires rhythmical activity of neurons. Memory-forming signal transmission in the hippocampus elucidated September 25, 2012 The hippocampus represents an important brain structure for learning.

Learning requires rhythmical activity of neurons

Scientists at the Max Planck Institute of Psychiatry in Munich discovered how it filters electrical neuronal signals through an input and output control, thus regulating learning and memory processes. Accordingly, effective signal transmission needs so-called theta-frequency impulses of the cerebral cortex. With a frequency of three to eight hertz, these impulses generate waves of electrical activity that propagate through the hippocampus. Zoom Image. Long-term stress. People differ enormously as to what they consider to be stressful and how they respond to it.

Too much stress causes changes in how hippocampal cells function. Chronic stress leaves cells in the hippocampus more vulnerable to injury, and fewer new cells are born. With severe, prolonged stress, hippocampal cells even die. Studies have shown loss of hippocampal volume and disruptions of learning and memory in people who are long-term sufferers of major depression, a psychiatric disorder that causes chronic stress. Chronic stress also decreases the release of dopamine in the brain’s reward pathway, blunting an individual’s capacity for pleasure and increasing the risk of depression. Long-term stress also leads to changes in the amygdala — a region involved in fear and anxiety — and the frontal cortex — a region key to planning and impulse control. Such changes can lead to increased anxiety and poor decision-making. This may explain why sometimes the decisions we make when stressed out may seem brilliant, but may lead to later regrets. – weihler

In general, short periods of moderate stress can actually be a good thing for the brain.

Long-term stress

For example, riding a roller coaster or watching an exciting movie sharpens our sensory and memory systems. In response to short-term stress, cells in the hippocampus — a region central to learning and memory — become more active. At the same time, there is an increase in the release of the brain chemical dopamine in the brain’s reward pathway, which is central to pleasure.

Activation.

Intrinsic (f.e. Hypothalamus), emotional (f.e. Amygdala), cognitive (f.e. Hippocampus, PFC), physical (f.e. Visual Cortex, Wernicke). – weihler

Activation, Conclusions. Activation and Learning. Forms of Activation, Measurement. Brain Researchers Open Door to Editing Memory. Adult Neurogenesis, Insights and Advances in ... Adult Neurogenesis, Insights and Advances in ... Chewing Rerduces Dementia Risk.

Researchers have looked at chewing ability and cognitive function in a random nationwide sample. They found that those who had difficulty chewing hard food such as apples had a significantly higher risk of developing cognitive impairments. Whether chewing ability was sustained with natural teeth or dentures also had no bearing on the effect. One reason for this could be that few or no teeth makes chewing difficult, which leads to a reduction in the blood flow to the brain. – weihler