Introducere in Neurostiinte Curs 2 (1)

7/27/2019 Introducere in Neurostiinte Curs 2 (1)

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INTRODUCERE IN NEUROSTIINTE



Trepanatii in Egiptul antic si Americaprecolumbiana

Galen – inteligenta se muta din inima in creier

Golgi si Cajal – doctrina neuronilor & PremiulNobel

Broca si Wernicke – zonele limbajului din

creier Brodmann si harta creierului




Scopul neurostiintelor

“The task of neural science is to explain behavior in terms of

the activities of the brain. How does the brain marshal its

millions of individual nerve cells to produce behavior, and

how are these cells influenced by the environment...? The

last frontier of the biological sciences – their ultimate

challenge – is to understand the biological basis of

consciousness and the mental processes by which we

perceive, act, learn, and remember” —

Eric Kandel(Laureat Nobel 2000 pentru descoperirea mecanismelor

invatarii)




Decade of the Brain 1990-1999

By the President of the United States o f America A PROCLAMATION

To enhance public awareness of the benefits to be derived from brain research, theCongress, by House joint Resolution 174, has designated the decade beginning January 1,1990, as the "Decade of the Brain" and has authorized and requested the President to issuea proclamation in observance of this occasion.

NOW, THEREFORE, I, GEORGE BUSH, President of the United States of America, dohereby proclaim the decade beginning January 1, 1990, as the Decade of the Brain. I callupon all public officials and the people of the United States to observe that decade withappropriate programs, ceremonies, and activities.

IN WITNESS WHEREOF, I have hereunto set my hand this seventeenth day of July in theyear of our Lord nineteen hundred and ninety, and of the Independence of the United Statesof America the two hundred and fifteenth.




Diviziiile neurostiintelor:

neurostiintele moleculare si

celulare

neurostiintele sistemelor

neurostiintele cognitive

neurostiintele comportamentului

neurostiintele afective neurostiintele sociale

neurostiintele dezvoltarii




Instrumentele neurostiintelor

Investigatia electrofiziologica – EEG, ERP, MEG

Investigatia imagistica structurala – CT, RMN

Investigatia imagistica functionala – PET, SPECT, RMNf

Investigatia celulara investigatia moleculara si genetica

Investigatia psihofarmacologica: neurotransmitatori si

efect medicatie




Electroencefalografie (EEG)

Masoara undele creierului :

• Alfa - relaxare

•

Beta –

asteptare incordata, stres• Gamma – perceptie, reamintire, constiinta

• Delta – meditatie, somn cu vise

• Theta – somn fara vise, invatare




Potentiale evocate relationate

cu un stimul (ERPs)

• CNV = componenta de pregatireinaintea unei sarcini cognitive

•

N100 = orientarea atentie (100-200ms de la paritia stimulului)

• N200 = detectarea trasaturilor deviante, a erorilor, a feedbackului(200 – 240 ms)

• P300 = incheierea procesarii unuistimul, reamintire, up-date memorie(250 ms de la aparitie)

• N400 = incongruente semantice (400ms de la aparitia stimulului)




Electroencefalografie (EEG)EEG uses electrodes applied to thescalp and measures changes in theelectrical field in the brain regionunderneath. EEG has very hightemporal resolution (milliseconds) andcan therefore detect brief neuronalevents. Because the skull disperses theelectrical field, EEG has low spatialresolution (~1 cm) that depends on how

many electrodes are used. The number of electrodes can be as few as two or range up to hundreds in high-densityarrays. The greater the number of electrodes, the better the spatialresolution. Apart from the low spatialresolution, EEG has poor sensitivity for

deep brain structures. Equipment costscan be low (<$10,000) but increase withhigh-density arrays and the concomitantresources needed to process the data.(Ariely and Berns, 2010).




Tomografie cu emisie de

pozitroni (PET)

• masoara undele gammaemise de substante izotopi aioxigenului injectate in sange

• detecteaza activitatea informatiuni cerebrale

• detecteaza concentratia unor neurotransmitatori

• dezavantaje – rezolutiispatiala si temporala mici


http://localhost/var/www/apps/conversion/tmp/scratch_10//upload.wikimedia.org/wikipedia/commons/c/c4/16slicePETCT.jpg



Rezonanta magnetica nucleara (MRI& fMRI)

The technique uses an MRI scanner tomeasure the blood oxygenation level-dependent (BOLD) signal. The BOLDchanges are generally correlated with theunderlying synaptic activity. Spatialresolution is 1 –10 mm, and temporal

resolution is 1 –10 s. In general, thehigher the spatial resolution, the lower the temporal resolution. fMRI has asubstantial advantage in resolving smallstructures and those that are deep in thebrain State of the art MRI scanners costapproximately US$1 million per

Tesla and have annual operating costs of $100,000 –$300,000. (Ariely & Berns,2010).




Proba de memorie de lucru n-back

Control

Depresiv 1

Depresiv

2




Spectroscopie RMN








Film



Hagmann si colab., 2008




Descoperirile au condus la o evaluare a impactului diverselor tipuri de

psihoterapii si medicatii - s-au dezvoltat noi tipuri de terapii S-au dezvoltat tehnici noi de invatare si re-invatare

S-au dezvoltat noi tipuri de instrumente de evaluare

S-au dezvoltat proteze

S-au dezvoltat modele mult mai exacte de intelegere si predictie a

comportamentului si performantei

Avantajele rezultate din neurostiinte:




Aplicatiile in business: neuroeconomics, neuromarketing, HR, etc.

















Film






Mesajul verbal

prezentat singur nu este

procesat si nu

declanseaza emotii

Combinatia imagine +

mesaj verbal conduce la

procesarea mesajului si

la declansarea de emotii

Doar imaginile explicite

au efect

Impactul

mesajului de

avertizare




Fiecare brand – prin logo-ul

prezentat – a fost

recunoscut ca semnificativ

de către subiecți evaluândactivarea în așa-numita

”regiune a brand-ului” din

creier, și anume cortexulventromedian prefrontal

Modul în care fiecare logo

sau ambalaj a captatatenția a fost evaluat prin

activările în zonelespecifice – cortex occipital,

median prefrontal

anterior, precuneus șinucleul caudat

Identificarea modului in

care un logo sau ambalaj a

declanșat emoție în

creierul subiecților a fostevaluat prin activările în:

cortexul ventromedian

prefrontal, cortex cingulatanterior, cortex

retrosplenial, nucleul

accumbens, putamen,

amigdală și aria ventrală

tegmentală


Documents

Introducere in Neurostiinte Curs 2 (1)