Reconsolidation Experiment

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Reconsolidation Experiment
Psychology 4870 Winter 2008
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24 Sprague Dawley rats from ACS will be placed on
restricted diet to bring them to 85 of
projected weight.
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The rats will be habituated to the cages and test
boxes used in the experiment. They will be
introduced to the Nestle Nesquik cereal which is
used as reinforcer
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Week 1-Habituation

• The rats will be placed in a cage identical to
  their home cage for 10 min with Nesquik cereal.
• The rats will then be transferred to a test box
  for 10 minutes with Nesquik cereal.
• Record the time spent eating the amount eaten
  in each 2 minute interval.
• Be very careful not to frighten rats note if
  the rats spend any time immobilized with fear.

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Apparatus

• Cage

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Apparatus

• Test Box

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Week 2 Learning

• The rats will each receive 5 training trials of
  the odor learning.
• On the first trial the reward will be visible.
  The reward will be placed on the almond-scented
  sponge as well as in the centre hole.
• On the remaining 4 trials the reward is placed in
  the hole of the almond scented sponge.
• The other sponges are scented with orange or
  vanilla.

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Trial 1 --- Visible treat
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Apparatus

• Glass dishes and sponge (with Nesquik morsel).

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Apparatus

• Test box showing rat in start position (top
  view).

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Apparatus

• Test box showing rat in start position (front
  view).

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Week 2 Learning (continued)

• Between trials the glass dishes will be switched
  with those from another group.
• The position of the 3 dishes will be varied in a
  systematic (quasirandom) way.
• The rat start position will not vary.

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Week 2 Learning (continued)

• Record the time for the rat to obtain the reward
  in seconds.
• Record the number of commission (poking at hole
  of wrong sponge) omission errors (not
  retrieving reward from correct sponge.)
• Allow the rat to eat the reward. Maximum trial
  duration is 5 minutes.
• Remove the rat from the test box.

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Week 2 Learning (continued)

• On the basis of performance during acquisition,
  the rats will be divided into 3 groups of rats.
• 8 rats will receive 4 mg/kg IP propranolol
  without memory reactivation (propranolol alone).
• 8 rats will receive 4 mg/kg IP propranolol with
  memory reactivation (odor propranolol).
• 8 rats will receive IP physiological saline with
  memory reactivation (odor vehicle).

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Week 2 Reconsolidation

• The day after acquisition, rats in the two groups
  undergoing memory reactivation will be brought up
  to the lab. Each rat will be placed in a cage
  with a glass dish sponge scented with almond
  for 90 seconds. There is no Nesquik reward.
• The rat will then be brought to a room adjacent
  to the lab injected with either propranolol or
  saline.
• The rat is then returned to his home cage and
  transported back to the holding room.

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Week 2 Reconsolidation (continued)

• Rats in the propranolol alone group will be
  injected with propranolol in the animal holding
  room and placed back into their home cages. Rats
  in this group will not be brought up to the
  classroom and will not be exposed to the almond
  odor.

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Week 3 --- Trial 1--- Memory Test

• The rats will be placed in the test box with 3
  glass dishes scented sponges. There will be no
  reward.
• Record the latency to visit first dish.
• Record the latency to visit correct (almond)
  dish.
• Record errors of commission and omission.

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Week 3 --- trials 2-5---Retraining

• These trials will be conducted exactly as done in
  week 2.

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Week 3---Trial 6 Memory Test

• This is a 5 minute trial without a reward.
• Record
• Time spent investigating almond scented dish.
• Time spent investigating other dishes (combined).
• Number of nose pokes - almond scented sponge.
• Number of nose pokes - other sponges (combined).