Chapter 3 Flashcards
Biological Bases of Motivation
What is the Reticular Formation and where is it?
I’s responsible for arousal, alertness and the process of awakening the brain to process incoming information. It’s located at the apex of the spinal cord where the spinal cord ends and the subcortical brain begins.
How many parts does the reticular formation compose of and what do they do?
It is composed of 2 parts:
1. The ascending reticular part: Where it is responsible for activating system projects to arise and awaken the brain.
2. The descending reticular part: That projects the nerves downward to regulate the body
What does the Amygdala do?
- Detects the aversive characteristics of environmental objects. –> Detects facial expressions of others (threat when angry) or happy expressions.
- Relay this emotion-laden information to neighbouring cortical and subcortical parts. –> Detects the absence of a reward or its presence. (Gambling example)
What happens when the amygdala is removed (Sometimes for medical reasons)
The person becomes calm, docile and emotionally indifferent even in threatening situations.
What is the Amygdala responsible for?
Detects learn about and responds to the stimulus properties of environmental objects, including threat-eliciting and reward eliciting associations.
Why do negative emotions tend to overpower cognition?
The Amygdala is connected to other parts of the brain and while it sends many projections to almost every part of the brain but receives few projections back. Therefore, it explains why there is an imbalance where emotions tend to overpower cognition more than cognition can regulate emotions.
What is the role of the lateral amygdala nuclei?
It forges reciprocal projections and pathways with the cortical brain (frontal lobes).
What does the Reward centre in the brain consist of?
- Striatum
- Nucleus Accumbens
- Ventral Tegmental Area
What is the reward centre?
It consists of several subcortical brain structures that communicate with one another via the dopamine network.
what is ventral striatum (Lower part)
Through its activation we know what to like, what to prefer and what to not like. Its also synonym of the experience of a reward.
What happens when there is a reward based stimuli?
- The Ventral Tegmental Area is activated and dopamine carries it across to the striatum and Nucleus Accombens to the Basil Ganglia, which translates the information to action.
The importance of the ventral tegmental area
It is where dopamine is manufactures and its starting point in the reward system.
Role of the orbitofrontal frontal cortex.
It’s where the learned reward experience is stored. Any environmental experiences that have resulted in pleasure will be stored in the orbitofrontal cortex and therefore it will resurface every time a similar experience occures.
VTA and the cortex area
Once VTA is activated it can go upstream to the cortical brain and it is in the prefrontal lobe that conscious pleasure occurs
What is the Brain Reward System
- It begins in the VTA where Dopamine is manufactured.
- The dopamine is then sent to the Nucleus Accumbens.
- The NA then sends it to the prefrontal cortex, which releases the experience of pleasure.
- Then to the orbitofrontal cortex, where the experience is stored.
