**L8 - Plasticity and Functional Recovery Flashcards
what is BRAIN PLASTICITY?
BRAIN PLASTICITY refers to the BRAIN’S ABILITY to CHANGE and ADAPT as a RESULT OF EXPERIENCE
PLASTICITY allows the brain to COPE BETTER with the INDIRECT EFFECTS of BRAIN DAMAGE, such as SWELLING or HAEMORRHAGE following a ROAD ACCIDENT, or the DAMAGE RESULTING FROM INADEQUATE BLOOD SUPPLY FOLLOWING A STROKE
how is BRAIN PLASTICITY and LIFE EXPERIENCE linked?
NERVE PATHWAYS that are USED FREQUENTLY DEVELOP STRONGER CONNECTIONS, those that are RARELY USED EVENTUALLY DIE
By developing NEW CONNECTIONS and REDUCING WEAK ONES, the brain is ABLE TO ADAPT to a CHANGING ENVIRONMENT. However, there is also a DECLINE IN COGNITIVE FUNCTIONING WITH AGE ATTRIBUTED TO THESE CHANGES.
BOYKE ET AL taught 60 YEAR OLDS A NEW SKILL (juggling), this INCREASED GREY MATTER in the VISUAL CORTEX - this shows the importance of keeping our BRAINS ACTIVE as we get older.
how is BRAIN PLASTICITY and VIDEO GAMES linked?
KUHN ET AL compared a CONTROL GROUP to a group who had been GIVEN VIDEO GAME TRAINING for AT LEAST 30 MINUTES A DAY FOR TWO MONTHS on the game ‘Super Mario’.
They found that PLAYING VIDEO GAMES caused a SIGNIFICANT INCREASE in GREY MATTER in the VISUAL CORTEX, HIPPOCAMPUS and CEREBELLUM
Playing video games results in NEW SYNAPTIC CONNECTIONS in BRAIN AREAS INVOLVED in SPATIAL NAVIGATION, STRATEGIC PLANNING, WORKING MEMORY and MOTOR PERFORMANCE
how is BRAIN PLASTICITY and MEDITATION linked?
DAVIDSON ET AL compared EIGHT PRACTITIONERS of TIBETAN MEDITATION with TEN STUDENTS who had NO PREVIOUS MEDITATION EXPERIENCE.
An EEG picked up GREATER GAMMA WAVE ACTIVITY in the MONKS, even BEFORE THEY STARTED MEDITATING.
Gamma waves COORDINATE NEURAL ACTIVITY
+ KEMPERMANN ET AL (EVALUATION OF PLASTICITY)
+ KEMPERMANN ET AL found FAR MORE NEW NEURONS in the BRAINS OF RATS in COMPLEX ENVIRONMENTS compared to those HOUSED IN BASIC CAGES
This INCREASE IN NEURONS was MOST PROMINENT in the HIPPOCAMPUS, which is involved in the FORMING OF NEW LONG TERM MEMORIES and the ABILITY TO NAVIGATE
+ MAGUIRE ET AL (EVALUATION OF PLASTICITY)
+ another strength of RESEARCH INTO BRAIN PLASTICITY comes from a supporting study conducted by MAGUIRE ET AL
MAGUIRE ET AL MEASURED GREY MATTER in the BRAINS OF LONDON TAXI DRIVERS using an MRI SCAN
The HIPPOCAMPUS was SIGNIFICANTLY LARGER than a CONTROL GROUP and this was POSITIVELY CORRELATED with the AMOUNT OF TIME THEY HAD SPENT as a TAXI DRIVER (the extent of their life experience)
what is FUNCTIONAL RECOVERY?
FUNCTIONAL RECOVERY is a FORM OF PLASTICITY. Following DAMAGE CAUSED BY TRAUMA, the brain can REDISTRIBUTE or TRANSFER FUNCTIONS usually performed by damaged areas to OTHER, UNDAMAGED AREAS.
When the brain is STILL MATURING, RECOVERY from trauma is MORE LIKELY, however, the brain is CAPABLE of PLASTICITY and FUNCTIONAL RECOVERY at ANY AGE. Studies have suggested that WOMEN RECOVER from a BRAIN INJURY QUICKER THAN MEN DO
how does the TRANSFER OF BRAIN FUNCTIONS HAPPEN?
TRANSFER OF FUNCTIONS from DAMAGED AREAS of the brain to UNDAMAGED ONES can occur, this is called NEURAL REORGANISATION.
Growth of NEW NEURONS and/or CONNECTIONS (axons or dendrites) to COMPENSATE FOR DAMAGED AREAS can also occur, this is called NEURAL REGENERATION.
AXON SPROUTING is part of NEURAL REGENERATION, NEW NERVE ENDINGS GROW AND CONNECT with OTHER UNDAMAGED NERVE CELLS to FORM NEW NEURAL PATHWAYS
what happens when the SPONTANEOUS RECOVERY SLOWS?
SPONTANEOUS RECOVERY from a brain injury TENDS TO SLOW DOWN after a NUMBER OF WEEKS so PHYSIOTHERAPY MAY BE REQUIRED to MAINTAIN IMPROVEMENTS in FUNCTIONING.
Techniques can include MOVEMENT THERAPY and ELECTRICAL STIMULATION OF THE BRAIN to COUNTER DEFICITS IN MOTOR and COGNITIVE FUNCTIONING that can be EXPERIENCED FOLLOWING A STROKE
+ PLS (EVALUATION OF FUNCTIONAL RECOVERY)
+ PHANTOM LIMB SYNDROME (PLS) can be USED AS EVIDENCE of NEURAL REORGANISATION
PLS is the CONTINUED EXPERIENCE of SENSATION in a MISSING LIMB, AS IF IT WAS STILL THERE
These SENSATIONS are OFTEN UNPLEASANT and EVEN PAINFUL. PLS is thought to be CAUSED BY NEURAL REORGANISATION in the SOMATOSENSORY CORTEX that occurs as the RESULT OF LIMB LOSS
+ HUBEL and TORTEN WISEL EVALUATION OF FUNCTIONAL RECOVERY)
+ HUBEN and TORTEN WISEL SEWED ONE EYE OF A KITTEN SHUT and ANALYSED the BRAIN’S CORTICAL RESPONSE
They found that the VISUAL CORTEX for the SHUT EYE WAS NOT IDLE (as was predicted) it CONTINUED TO PROCESS INFORMATION FROM THE OPEN EYE
This is FURTHER EVIDENCE that BRAIN AREAS can REORGANISE THEMSELVES and ADAPT THEIR FUNCTIONS
