regeneration of mind and brain

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REGENERATION OF MIND AND BRAIN

REGENERATION OF MIND AND BRAIN

Devashish konar MD Consultant Psychiatrist Mental Health Care Centre, Kolkata and BurdwanM: +91 9434009113

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THE MIND BOGGLING COMPLEXITIES OF THE MASTER ORGAN BRAINThe human nervous system is the organ of consciousness, cognition, ethics, and behavior; as such, it is the most intricate structure known to exist.More than one-third of the 23,000 genes encoded in the human genome are expressed in the nervous system. Each mature brain is composed of 100 billion neurons, several million miles of axons and dendrites, and >1015 synapses. Neurons exist within a dense parenchyma of multifunctional glial cells that synthesize myelin, preserve homeostasis, and regulate immune responses.Measured against this background of complexity, the achievements of molecular neuroscience have been extraordinary.2

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ACHIEVEMENTS ARE COMMENDABLE AND TASKS ARE GIGANTIC In spite of better understanding of brain physiology in the last 25 years, the fact remains that psychiatric illnesses are on increase and we have not made any strong headway in preventing these illnesses. All serious psychiatric illnesses from depression to schizophrenia to dementia have neuronal degeneration in different areas of brain.Increased levels in oxidative stress, mitochondrial dysfunction, excitotoxicity, inflammatory changes, iron accumulation, and protein aggregation are some of the common ways in which neuronal degeneration occurs. For neuroprotective treatment you need to focus on these pathologies.

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REGENERATION OF BRAIN AND MIND: MAJOR THRUST AREA OF FUTURE NEUROSCIENCESWith new methods in basic neuroscience we have improved our understanding of neurodegeneration and regeneration.Natural methods, like life style changes and drugs which can alter the health of neuronal tissue have been worked upon and some important clues have been found.

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THE ACUMULATING CLUES TO OUR UNDERSTANDING

Glutamate receptors, specifically N-Methyl-D-Aspartate (NMDA) receptorsGlutamate antagonistsAntioxidantsBrain-derived neurotrophic factor (BDNF) and other neurotrophin family of growth factors Insulin receptors are the latest to have increased our understanding of molecular psychiatry

As more data accumulate time will be ripe to translate these understanding into bedside wisdom

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FUNCTIONS OF NEUROTROPHIC FACTORSNeurotrophic factors are secreted proteins that modulate neuronal growth, differentiation, repair, and survival; some have additional functions, including roles in neurotransmission and in the synaptic reorganization involved in learning and memory.6

PRINCIPLES OF INTERNAL MEDICINE, HARRISONS 19TH EDITION

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7TNeurotrophin familyNerve growth factorBrain-derived neurotrophic factorNeurotrophin-3Neurotrophin-4Neurotrophin-6

Cytokine familyCiliary neurotrophic factorLeukemia inhibitory factorInterleukin 6Cardiotrophin-1

Transforming growth factor familyGlial-derived neurotrophic familyNeurturinPersephinFibroblast growth factor family

Hepatocyte growth factor

Insulin-like growth factor (IGF) familyIGF-1IGF-2

NEUROTROPHIC FACTORS

PRINCIPLES OF INTERNAL MEDICINE, HARRISONS 19TH EDITION

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CONTRARY TO CONVENTIONAL THOUGHT AS EXPRESSED IN THIS DIAGRAM, BRAIN FUNCTIONS ARE NOT CONFINED TO CERTAIN FIXED LOCATIONS

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From Wikipedia, the free encyclopedia

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NEUROPLASTICITYNeuroplasticity, also known as brain plasticity, is an umbrella term that describes lasting change to the brain throughout an animal's life course. The term gained prominence in the later half of the 20th century, when new research showed many aspects of the brain remain changeable (or "plastic") even into adulthood. This notion contrasts with the previous scientific consensus that the brain develops during a critical period in early childhood, then remains relatively unchangeable (or "static") afterward.9

From Wikipedia, the free encyclopedia

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NEUROPLASTICITYNeuroscientists distinguish synaptic plasticity, which refers to changes in how neurons connect to each other, from non-synaptic plasticity, which refers to changes in the neurons themselves.One of the fundamental principles of how neuroplasticity functions is linked to the concept of synaptic pruning, the idea that individual connections within the brain are constantly being removed or recreated, largely dependent upon how they are used. This concept is captured in the aphorism, "neurons that fire together, wire together"/"neurons that fire apart, wire apart," summarizing Hebbian theory. If there are two nearby neurons that often produce an impulse simultaneously, their cortical maps may become one. This idea also works in the opposite way, i.e. that neurons which do not regularly produce simultaneous impulses will form different maps.

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From Wikipedia, the free encyclopedia

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I WILL GIVE YOU FOUR EXAMPLESHuman echolocation in visually impairedLearning difficultyADHDPhantom limbs

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From Wikipedia, the free encyclopedia

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HUMAN ECHO-LOCATIONHuman Eco-location is a learned ability for humans to sense their environment from echoes. This ability is used by some blind people to navigate their environment and sense their surroundings in detail.Studies in 2010 and 2011 using functional magnetic resonance imaging techniques have shown that parts of the brain associated with visual processing are adapted for the new skill of echolocation.Studies with blind patients, for example, suggest that the click-echoes heard by these patients were processed by brain regions devoted to vision rather than audition.12

From Wikipedia, the free encyclopedia

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LEARNING DIFFICULTYMichael Merzenich developed a series of plasticity-based computer programs known as Fast Forword. FastForWord offers seven brain exercises to help with the language and learning deficits of dyslexia.In a recent study, experimental training was done in adults to see if it would help to counteract the negative plasticity that results from age-related cognitive decline (ARCD). The experimental training design included six exercises designed to reverse the dysfunctions caused by ARCD in cognition, memory, motor control, and so on. After use of the experimental training program for 810 weeks, there was a significant increase in task-specific performance.The data collected from the study indicated that a neuroplasticity-based program could notably improve cognitive function and memory in adults with ARCD.

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From Wikipedia, the free encyclopedia

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ADHDReviews of magnetic resonance imaging (MRI) studies suggest that the long-term treatment of attention deficit hyperactivity disorder (ADHD) with stimulants, such as amphetamine or methylphenidate, decreases abnormalities in brain structure and function found in subjects with ADHD, and improves function in several parts of the brain, such as the right caudate nucleus of the basal ganglia.

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From Wikipedia, the free encyclopedia

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PHANTOM LIMBSThe experience of Phantom limbs is a phenomenon in which a person continues to feel pain or sensation within a part of their body which has been amputated. This is strangely quite common, occurring in 6080% of amputees. An explanation for this refers to the concept of neuroplasticity, as the cortical maps of the removed limbs are believed to have become engaged with the area around them in the postcentral gyrus. This results in activity within the surrounding area of the cortex being misinterpreted by the area of the cortex formerly responsible for the amputated limb.

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From Wikipedia, the free encyclopedia

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PHANTOM LIMBSThe relationship between phantom limbs and neuroplasticity is a complex one. In the early 1990s V.S. Ramachandran theorized that phantom limbs were the result of cortical remapping. In 1995 Herta Flor and her colleagues demonstrated that cortical remapping occurs only in patients who have phantom pain. Her research showed that phantom limb pain (rather than referred sensations) was the perceptual correlate of cortical reorganization. This phenomenon is sometimes referred to as maladaptive plasticity.With treatment, pain relief is possible in many, though not always.

Findings extend our understanding of the brain's plasticity because there is evidence that profound changes in the mental representation of the body can be induced purely by internal brain mechanismsthe brain truly does change itself.

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From Wikipedia, the free encyclopedia

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NEUROGENESIS, MIGRATION AND CELL REPLACEMENTFrom clinical and therapeutic perspectives, fundamental questions are whether changes in neurogenesis contribute to disease and whether newly formed neurons undergo migration to and integration into regions of injury, replacing dead cells and leading to functional recovery. A neurogenetic response has now been shown for multiple conditions in the adult, including brain trauma, stroke, and epilepsy. For instance, ischemic stroke in the striatum stimulates adjacent subventricular zone (SVZ) neurogenesis with neurons migrating to the injury site. Furthermore, in a highly selective paradigm not involving local tissue damage, degeneration of layer 3 cortical neurons elicited subventricular zone (SVZ) neurogenesis and cell replacement.17

SYNOPSIS OF PSYCHIATRY, Behavioral sciences / Clinical Psychiatry 11th Edition, by Kaplan & Sadocks, Page no-34-3517

NEUROGENESIS: THE OTHER IMPLICATIONSThese studies raise the possibility that newly produced neurons normally participate in recovery and may be stimulated as a novel therape