Biology - Antonova (2011)

Question 1

Antagonist

Answer 1

A chemical or drug that binds to brain receptors and prevents a neurotransmitter or
hormone from affecting behavior. For example, scopolamine is an antagonist for acetylcholine

Question 2

Acetylcholine

Answer 2

The most common neurotransmitter. Acetylcholine receptor sites are found in the
hippocampus. It appears that acetylcholine plays a key role in memory consolidation from STM
to LTM

Question 3

Agonist

Answer 3

A chemical or drug that binds to receptors in the brain and causes a reaction. Agonists
can occur naturally in the body as hormones and neurotransmitters (endogenous agonists) or
come from exterior sources like drugs and toxins

Question 4

Functional Magnetic Resonance Imaging (fMRI)

Answer 4

A series of MRIs measuring brain function via
a computers combination of multiple images taken less than a second apart- show activity in the
brain over time

Question 5

Excitatory Function

Answer 5

: When a neurotransmitter increases the likelihood that the neuron will fire
an action potential. This depends on the receptor site. Many neurotransmitters are excitatory
when they act on some receptor sites, and inhibitory when they act on others

Question 6

Aim

Answer 6

: Determine is scopolamine affected hippocampal activity in the creation of spatial memory

Question 7

Procedure

Answer 7

Participants randomly allocated to conditions.
- Injected with either Scopolamine or a placebo 70-90 minutes before starting
- Put into an fMRI where they were scanned while playing the “Arena task” (virtual reality
game testing individuals’ spatial memory) (participants were asked to find a pole in the
arena, then the screen went black for them to rehearse the location of the pole, and then
the participant was at a new starting point in the arena and they would have to use their
spatial memory to find the pole again).
- Returned 3-4 weeks later to redo the test- receiving the opposite treatment

Question 8

Results

Answer 8

When participants were injected with scopolamine, they demonstrated a significant
reduction in the activation of the hippocampus compared to when they received a
placebo. Appears that acetylcholine could play a key role in the encoding of spatial
memories

Question 9

Evaluation

Answer 9

• Higher rate of error in scopolamine group but there was not a significant difference- the
  difference in activity in the hippocampus was significant- without the use of an fMRI
  there would be no way to know at the biological level that there was a difference
• Study was carried out blindly, controlling researcher bias
• During the debriefing, several of the participants expressed that they had felt stressed,
  either as a result of the injection of an unfamiliar drug or being in the fMRI enclosurethis could have an effect on the working of the hippocampus as we know stress may
  interfere with memory encoding