za pedagoge mozak ucenje2013 - st- · pdf filemozak prošao je veliki put od “crne...
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3/4/13
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Suvremene spoznaje o funkcioniranju mozga i
mehanizmima učenja i pamćenja
Prof. dr. sc. Zoran Đogaš, dr. med. Prodekan za nastavu MF u Splitu Predstojnik Zavoda za neuroznanost, MF u Splitu Voditelj Centra za medicinu spavanja, MF u Splitu i KBC Split Predsjednik Hrvatskoga somnološkog društva-društva za medicinu spavanja HLZ-a European Sleep Research Society, Board Member Assembly of European National Sleep Societies, co-chair of Executive Committee
University of Split, School of Medicine; Department of Neuroscience
Split, 1. ožujka 2013.
12. Tjedan mozga u Splitu i u RH
11.-17. ožujka 2013.
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
TEME PREDAVANJA:
• Vrste učenja i pamćenja • Pozornost (primjer vidne pozornosti) • Stanična građa mozga (i korteksa) • Komunikacija u mozgu • Plastičnost mozga • Stanični mehanizmi učenja i pamćenja (neasocijacijskog i asocijacijskog)
University of Split, School of Medicine; Department of Neuroscience
Vrste učenja i pamćenja
• Neasocijacijsko • Habituacija i senzitizacija
• Asocijacijsko • Klasično kondicioniranje • Operantno kondicioniranje
• Eksplicitno i implicitno učenje i pamćenje
Učenje
Asocijacijsko – organizam uči ili o međusobnom odnosu više različitih podražaja (klasično kondicioniranje Pavlovljevog tipa) ili o odnosu podražaja i vlastitog djelovanja (instrumentalno ili operantno kondicioniranje Thorndike-Skinnerovog tipa).
Neasocijacijsko – organizam jednom ili ponavljano izložen podražaju, uči svojstva tog podražaja
University of Split, School of Medicine; Department of Neuroscience
Složeno asocijacijsko pamćenje
-eksplicitno (deklarativno)
-implicitno (proceduralno)
University of Split, School of Medicine; Department of Neuroscience
Pozornost -Usmjeravanje pozornosti
Odabir osjetnih informacija (tjemeni režanj) Preduvjet: usklađenost osjetnih mapa i personalnog (peri- i ekstra-) prostora
Primjer: vidna pozornost (PREDUVJETI: budnost, motivacija, vidna mapa,
okulomotori, vidno pamćenje, pa tek onda percepcija – UČENJE)
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
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University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
O tell me where is fancy bred Or in the heart, or in the head
William Shakespeare
Egyptian hieroglyphics for the word “brain”
17. century B.C.
The earliest known reference to the human brain
University of Split, School of Medicine; Department of Neuroscience
University of Split, School of Medicine; Department of Neuroscience
Zadnje desetljeće 20. stoljeća nazvano u znanosti Dekada mozga,
a 21. stoljeće – Stoljeće uma
Understanding the biology of brain function is a major goal of modern
science
neuroni
University of Split, School of Medicine; Department of Neuroscience
Piramidnineuronkralješnjaka SOMA
DENDRITI
AKSON
University of Split, School of Medicine; Department of Neuroscience
Podjela neurona
University of Split, School of Medicine; Department of Neuroscience
Neuroni moždane kore
University of Split, School of Medicine; Department of Neuroscience
KOMUNIKACIJA U MOZGU (SIGNALIZACIJA)
University of Split, School of Medicine; Department of Neuroscience
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University of Split, School of Medicine; Department of Neuroscience
Sinapsa
University of Split, School of Medicine; Department of Neuroscience
primjeri sinapsnih veza
University of Split, School of Medicine; Department of Neuroscience
Sinaptička veza
University of Split, School of Medicine; Department of Neuroscience
Acetilkolinski receptori
University of Split, School of Medicine; Department of Neuroscience
ACh receptor (nAChR)
computer rendering imaged by cryo-electron microscopy
University of Split, School of Medicine; Department of Neuroscience
Dopaminski receptor
University of Split, School of Medicine; Department of Neuroscience
Serotoninski unositelj
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
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Klasični neurotransmiteri
GABA, glutamat serotonin, dopamin acetilkolin, (nor)adrenalin, histamin
University of Split, School of Medicine; Department of Neuroscience
GABA (-)
Inhibicija Ekscitacija
GLUTAMAT (+)
RAVNOTEŽA
University of Split, School of Medicine; Department of Neuroscience
GABA (-) Inhibicijska aminokiselina
Ekscitacijska aminokiselina
GLUTAMAT (+)
Hiperpolarizacija → Inhibicija
Depolarizacija → Ekscitacija
IPSP
EPSP
University of Split, School of Medicine; Department of Neuroscience
kemijska reakcija nastanka GABA-e iz glutamata
University of Split, School of Medicine; Department of Neuroscience
“Razgovor” dvaju neurona
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
Tek nakon mnogo signala i “zbrajanja”
Visoko aktivno
neaktivno University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
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MOZAK PROŠAO JE VELIKI PUT OD “CRNE KUTIJE”
DO TJEDNA MOZGA
University of Split, School of Medicine; Department of Neuroscience
Učenje i pamćenje 38 University of Split, School of Medicine; Department of Neuroscience
Rinalni korteks – novo dugoročno eksplicitno pamćenje Hipokampus – dugoročno pamćenje položaja u prostoru Amigdala – pamćenje čuvstvenih značenja određenih iskustava Sekundarni senzorni korteks i asocijativni korteks – neuralni krugovi za pohranu dugoročnog pamćenja Implicitno pamćenje – senzomotorički zadaci – mali mozak i strijatni sustav (dopaminergičke strukture – kaudatus i putamen) Prefrontalni korteks – vremenski slijed događaja
University of Split, School of Medicine; Department of Neuroscience
PLASTIČNOST MOZGA
University of Split, School of Medicine; Department of Neuroscience
Neasocijacijsko učenje
• Senzitizacija (pseudokondicioniranje) je jačanje reakcije organizma na raznolike podražaje što se jave odmah nakon jednog snažnog i/ili štetnog podražaja (kad nas netko bocne iglom, a potom tek blago dodirne, trzamo se i na taj blagi dodir). “Narodne izreke”
• Habituacija je slabljenje reakcije organizma na ponavljani, a neštetni ili beznačajni podražaj (bušilica).
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
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University of Split, School of Medicine; Department of Neuroscience
Složeno asocijacijsko pamćenje
eksplicitno (deklarativno)
implicitno (proceduralno)
University of Split, School of Medicine; Department of Neuroscience
Eksplicitno pamćenje
Stječemo svjesnim naporom, a tako se i prisjećamo onog što smo procesom eksplicitnog učenja upamtili.
Stoga takvo znanje možemo iskazati (deklarirati – otuda naziv deklarativno pamćenje).
University of Split, School of Medicine; Department of Neuroscience
Anterogradna amnezija: bolesnik H.M. U rujnu 1953. kanadski neurokirurg Scoville je operativno
odstranio prednji dio oba sljepoočna režnja mladom muškarcu (Henry Gustav Molaison) koji je trpio od teške i neizlječive epilepsije. Tim su zahvatom odstranjene sljedeće strukture: vrh temporalnog režnja, uncus i amygdala, formatio hippocampi i susjedni dio parahipokampalne vijuge. Mladić se doista izliječio od epilepsije. No, javila se nova vrsta moždanog poremećaja: anterogradna amnezija. Svojstva tog poremećaja na ovom slavnom pacijentu su potanko proučena tijekom 30 godina sustavnog psihološkog testiranja.
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
U sljepoočnom režnju smještene su strukture bitne za eksplicitno pamćenje:
hippocampus
susjedna mezokortikalna područja cortex entorhinalis (polje 28) cortex perirhinalis (polje 35) ostatak parahipokampalne vijuge i vrh
sljepoočnog režnja.
University of Split, School of Medicine; Department of Neuroscience
52 University of Split, School of Medicine; Department of Neuroscience
Nakon pacijenta H.M. vršeni su brojni pokusi na pokusnim životinjama s lezijama Hipokampusa i Amigdala
H+A+ lezija: uklonjeni hipokampalna formacija (H) i amigdala (A)
Studije pamćenja
University of Split, School of Medicine; Department of Neuroscience
Uloga hipokampusa u pamćenju
1986. opis bolesnika R.B., koji je dobio izraženi i dugotrajni poremećaj pamćenja (amneziju) nakon globalne ishemije mozga. Pacijent je kasnije umro, a obdukcija je pokazala da su moždana oštećenja pogodila jedino polje CA1 u oba hipokampusa.
University of Split, School of Medicine; Department of Neuroscience
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Pacijent R.B. Učinci selektivnog
oštećenja hipokampusa – sloj piramidnih stanica u potpolju CA1
55 University of Split, School of Medicine; Department of Neuroscience
Uloga hipokampusa u pamćenju
Hipokampus je smanjen u bolesnika s ograničenim poremećajima pamćenja.
PET studije pokazale su da tijekom rješavanja psiholoških testova pamćenja do aktivacije dolazi upravo u području hipokampusa i parahipokampalne vijuge.
Majmuni CA1, CA2 i CA4 polja
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
Primjer plastičnosti mozga
DUGOROČNA POTENCIJACIJA LTP-Long Term Potentiation
Stanični mehanizam učenja i pamćenja
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
Kako izazvati i snimiti LTP?
Sinaptička veza
University of Split, School of Medicine; Department of Neuroscience
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NO
+ GLUTAMAT (NMDA)
University of Split, School of Medicine; Department of Neuroscience
Stanični mehanizam učenja i pamćenja
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience
Učenje – primjer plastičnosti mozga DUGOROČNA POTENCIJACIJA
LTP-Long Term Potentiation Stanični mehanizam učenja i pamćenja
University of Split, School of Medicine; Department of Neuroscience
BUDIMO PODRAŽAJ ZA STVARANJE LTP-a
TIME ĆEMO STVORITI I NOVE SINAPSE U MOZGU NAŠIH UČENIKA/STUDENATA
University of Split, School of Medicine; Department of Neuroscience
Svrha podučavanja? Ostvarujemo li je ili...?
The purpose of an education is to fill vessels and to light fires...
Today, we fill the vessels so full, they overflow and put out the fire...
University of Split, School of Medicine; Department of Neuroscience
HVALA NA POZORNOSTI!
University of Split, School of Medicine; Department of Neuroscience University of Split, School of Medicine; Department of Neuroscience