Van Den Oever - Aim and Procedure

What is the full name of Van den Oever's study?

Van den Oever et al 2008 Prefrontal Cortex AMPA Receptor Plasticity is Crucial for Cue Induced Relapse to Heroin Seeking Behaviour

What was the aim?

to investigate changes in (the) composition and function of synapses in (the) medial prefrontal cortes upon reexposure to heroin cues after long term abstinence

What were the participants?

hundreds (of) male waster rats

What was an advantage of skinners box?

allowed (the) researcher to control all extra variables such as social interaction and situational environmental factors creating a mini laboratory setting to model human experience

Describe the process of self administration of heroin?

light and buzzer, if rat pokes nose through hole, heroin dose through catheter

What were the drug associated cues?

light and buzzer

What was the drug seeking behaviour?

nose poking

What was modelled by the light and buzzer, and nose poking?

drug associated cues and drug seeking behaviour

What is an advantage of using animals in this study?

scientific as allows objective data collection and high control, standardised procedures

What are three examples of standardised procedures?

biological control as all male, same audiovisual cues, same amount of heroin (each time)

What was the focus of the study?

concerned with biological changes in (the) brain linked to heroin addict relapse upon reexposure to drug associated cues

What changes in the brain did van den oever specifically look for?

changes in AMPA receptors on (the) postsynaptic neurones in (the) mPFC

What are AMPA receptors?

receptors for the neurotransmitter glutamate which is linked with reward pathways

What was the name of stage 1?

self( )administration of heroin

What happened to the experimental group during stage 1?

trained to self( )administer heroin upon audiovisual cues

What happened to the control group during stage 1?

trained to self( )administer a sucrose solution

Why was a control group used?

to ensure that any neurobiological changes were due to heroin and not just any reward

What is the name of stage 2?

abstinence and extinction

What happened to the experimental group in stage 2?

split into two groups

What happened to the abstinence group in stage 2?

kept in separate cage for 21 days with no heroin

What happened to the extinction group in stage 2?

left in (the) self administration box for 21 days with no heroin

What difference was found between the abstinence and extinction groups?

none

What is the name of stage 3?

reexposure to drug associated cues

What happened to the abstinence and extinction groups in stage 3?

split into two groups

What happened to group 1 in stage 3?

reexposed to drug associated cues for 60 mins with no heroin

What happened to group 2 in stage 3?

not exposed to drug associated cues for 60 mins with no heroin

Why was group 2 in stage 3 necessary? (not exposed to drug cues)

control to confirm that any synaptic changes were due to (the) drug associated cues

What was the measure of relapse?

nose poking

What was the name of stage 4?

analysis of composition and function of synapses in (the) mPFC

What happened to all rats in stage 4?

decapitated and their brains frozen and analysed using mass spectrometry

What is mass spectrometry?

analytical technique to identify the amount and types of chemicals present in a microscopic sample allowing detection of subtle changes in receptor proteins