Michael S. Fanselow Department of Psychology UCLA &n by s2939Sm

VIEWS: 4 PAGES: 16

									       Michael S. Fanselow
      Department of Psychology
              UCLA




                                                   Quic kTime™ and a
                                         TIFF (Uncom press ed) decompres sor
                                            are needed to see this pic ture.




http://www.psych.ucla.edu/fanselowlab/
• First step is to understand that fear evolved
  because it is good for us.
• It evolved because behaving in certain
  ways protects us in times of danger.
• Fear is a Functional Behavior System and
  its physical basis is the parts of the nervous
  system that recognize danger and
  generate defensive behaviors.
• Example of how evolution crafted our
  behavior.
• Powerful Emotion-Psychiatric Disorders
• Model System for Learning
               Pavlovian Conditioning
                                        QuickTime™ and a
                               TIFF (Uncompressed) decompre ssor
                                  are neede d to see this picture.




        Bell                                                                 Food
Conditional Stimulus                                                 Unconditional Stimulus
       Tone                                                                  Shock

                                QuickTime™ and a
                       TIFF (Uncompressed) decompressor
                          are neede d to see this picture.




                 Salivate                                                               Salivate
           Conditional Response                                                 Unconditional Response
               Fear (freeze)                                                           Pain (jump)
• Example of how evolution crafted our
  behavior.
• Powerful Emotion-Psychiatric Disorders
• Model System for Learning
  – Insight into memory & its failure--how long
    does a fear memory last?
Train:                    1 week
Context-->Shock Pairing


                          1.3 years




                          novel
                    Fear: a memory that lasts forever
                         (or at least >1.3 years in the adult rat)

               80
               70
Freezing (%)



               60
               50
               40
               30
               20
               10

                          1.3 years                1 Week Novel
                                                       Gale et al., 2004. J. Neurosci., 24, 3810-3815.
• Example of how evolution crafted our
  behavior.
• Powerful Emotion-Psychiatric Disorders
• Model System for Learning
  – Insight into memory & its failure
  – How experience changes the brain
• We now know the circuit or pathway from
  sense organs to muscles.
• A critical part of the brain is a small almond
  shaped area in the medial temporal lobe
  called the amygdala.
                                                  QuickTime™ and a
                                        TIFF (Uncompressed) decompre ssor
                                           are neede d to see this picture.
Normally you need the amygdala to either learn or express fear
              80



              60
    Freezing (%)



              40



              20




                   Muscimol ACSF
                                                                                                                  Unconditional Stimuli




                                                                       NMDA-Receptor Was glutamate released?
                                                                               QuickTime™ and a
                                                                           TIFF (LZW) decompressor
                                                                                   e
                                                                                            cTm
                                                                                         Q ui ki e™ ad a
                                                                                  TI FF( LZW) dcom pr esor
                                                                                                e
                                                                                                     n
                                                                                                   s c
                                                                                                          s
                                                                              ar e neded t osee t hi pi t ur e.

                                                                        are needed to see this picture.


                                                   Did my cell fire?
                                                                                                                               Conditional Stimuli
 Hey nucleus, turn on                                                                                                          (releases glutamate)
 genes that will give
 me some more AMPA
 receptors

                                                                                 QuickTime™ and a
                                                                             TIFF (LZW) decompressor
                                                                          are needed to see this picture.




                                                                         AMPA-Receptor

                                                                                                                                             QuickTime™ an d a
                                                                                                                                    TIFF (Uncompressed) decompressor
                                                                                                                                       are need ed to see this picture.




            Q uic kT ime ™ a n d a
T IFF (U n co mp r e ss e d) de c om p re s so r
                              s c
    a re n ee d ed to s ee th i p i tu re .
                                                                                                                     Unconditional Stimuli




                                                                          NMDA-Receptor Was glutamate released?
                                                                                  QuickTime™ and a
                                                                              TIFF (LZW) decompressor
                                                                                      e
                                                                                               cTm
                                                                                            Q ui ki e™ ad a
                                                                                     TI FF( LZW) dcom pr esor
                                                                                                   e
                                                                                                        n
                                                                                                      s c
                                                                                                             s
                                                                                 ar e neded t osee t hi pi t ur e.

                                                                           are needed to see this picture.


                                                      Did my cell fire?
                                                                                  QuickTime™ and a
                                                                                                                                  Conditional Stimuli
                                                                              TIFF (LZW) decompressor
    Hey nucleus, turn on                                                   are needed to see this picture.                        (releases glutamate)
    genes that will give
    me some more AMPA                                                       AMPA-Receptor
    receptors
      QuickTime™ and a
                                                                          When I see glutamate,
   TIFF (L ZW) deco mpressor                                              I tell my cell to FIRE!
are needed to se e this picture.




               Q uic kT ime ™ a n d a
   T IFF (U n co mp r e ss e d) de c om p re s so r
                                 s c
       a re n ee d ed to s ee th i p i tu re .
• When the level of fear is inappropriate to the threat.
  – Endorphins (natural morphine like chemicals)
• When we become afraid in inappropriate situations


                QuickTime™ and a
            TIFF (LZW) decomp resso r
         are neede d to see this picture.            QuickTime™ an d a
                                                 TIFF (LZW) decomp resso r
                                              are need ed to see this picture .




                                                   QuickTime™ and a
                                               TIFF (LZW) decompressor
                                            are neede d to see this picture.
• Treatment: Extinction teaches the brain not to fear.
   – Beginning to understand the neural mechanisms of
     extinction--so we can facilitate behavioral therapy.
• Understand how conditions like Post-traumatic
  Stress Disorder change how the fear system
  functions.
• How the brain can compensate for damage.
           Thanks!
       Michael S. Fanselow
      Department of Psychology
              UCLA




                                                   Quic kTime™ and a
                                         TIFF (Uncom press ed) decompres sor
                                            are needed to see this pic ture.




http://www.psych.ucla.edu/fanselowlab/

								
To top