Discuss the effect of one or more neurotransmitters on behaviour.

Refer to the paper 1 section B assessment criteria when awarding marks. These can be found under the “Your tests” tab > supplemental materials. 

The command term “discuss” requires candidates to offer a considered review of the effect of neurotransmitters on behaviour.

Behaviour in this instance may include emotion, motivation, memory or any other accepted behaviour.

Neurotransmitters and relevant effects on behaviour include, but are not limited to:

• the effect of serotonin in regulation of mood
• the effect of dopamine in motivation and the experience of pleasure
• the effect of acetylcholine in memory.

Candidates may use animal studies to discuss neurotransmitters as long as the discussion focuses on a behaviour.

Relevant studies may include, but are not limited to:

• Rogers and Kesner (2003); Antonova (2011) on the role of acetylcholine in memory
• Crockett et al. (2010) on the effect of serotonin on prosocial behaviour
• Passamonti et al.’s (2012) study on the effect of tryptophan depletion on amygdala activity in relation to fear
• Fisher, Aron, and Brown’s (2005) study on the role of dopaminergic pathways in romantic love.

Discussion may include, but is not limited to:

• difficulties in carrying out research on neurotransmission
• generalizability of animal research to human behaviour
• ethical considerations in research into the effects of neurotransmitters
• the use of a reductionist approach to explain complex human behaviours
• the interaction of environmental and biological factors in behaviour
• applications of our understanding of the effect of neurotransmitters on behaviour, such as in the treatment of psychological disorders.

Candidates may discuss one neurotransmitter in order to demonstrate depth of knowledge, or may discuss more than one neurotransmitter in order to demonstrate breadth of knowledge Both approaches are equally acceptable.

There were many strong responses to this question where candidates demonstrated a solid understanding of the effect of neurotransmitters on behaviour. More robust responses described the process of synaptic transmission and specific neurotransmitters' functions; most common of these were dopamine, serotonin and acetylcholine. Weaker responses discussed hormones instead of neurotransmitters and described inappropriate research.

Relevant psychological research was described in detail, and there was an impressive variety of empirical evidence demonstrated which supported the effects of one or more neurotransmitters on behaviour. Many candidates described animal research, although there was a lack of clarity regarding the effects on human behaviour. Familiar problems associated with critical thinking persisted, and many responses provided generic evaluation statements, demonstrating a poor grasp of this skill, often using a methodological evaluation.