BLOA Content Flashcards
What are neurons?
• nerve cell involved in behaviour. They send electrochemical messages to the brain so that people people can respond to a stimulus, this transfer of messages is known as neurotransmission.
Define neurotransmission
the method in which messages are sent through the central nervous system
Explanation of neurotransmission
- when a nerve impulse reaches the end of the neuron, the neuron fires and neurotransmitters are released into the synaptic gap where they travel to the neuron at the other end of the synaptic gap.
- If the neurotransmitter is not absorbed it can be re-uptaken, diffused or destroyed. The neurotransmitter then binds to specific receptors at the other side. If a neurotransmitter is blocked or replaced (eg, because another chemical interferes) than the messages change. This affects the physiological system, cognition, mood or behaviour.
What is dopamine
- what is it involved in
- where is it released fro
- what increases it
a neurotransmitter involved in motivation such as pleasure-seeking, control of movement, emotional response and addictive behaviour. It is released in the brains reward system.
• Addictive drugs or substances increase the amount of dopamine in the reward system.
• It can be released by environmental triggers eg. Sight of food, cirgarette package, because this is associated with pleasure.
What is acetylcholine?
a neurotransmitter which has been linked to synaptic plasticity in the hippocampus and appears to play an important role in the learning and short-term memory via the cholinergic system (Shinoe et al 2005).
What is the cholinergic system?
a system of cells that uses acetylcholine in transmitting nerve signals. Memory processing and higher cognitive functioning are dependent on the cholinergic.
Do neurotransmitters effect behaviour?
Neurotransmission is an effective way to communicate messages through the brain. Therefore, neurotransmitters such as dopamine and acetylcholine affect specific human behaviours such as goal-directed behaviour and memory. Overall it can be concluded that neurotransmitters do affect human behaviour in a variety of ways.
What is melatonin?
a hormone that plays an important role in the entrainment of our circadian rhythms.
What is entrainment?
What are circadian rhythms?
The matching of physiological processes to changes in the environment.
Circadian rhythms= physiological processes that work accordingly to roughly 24 hour cycles.
An example of the entrainment of a circadian rhythm is the use of external cues about daylight to change when we feel tired. Melatonin plays a crucial role in this entrainment process.
Melatonin in entrainment process
- where is it secreted
- what receives info from sense organs
- when is it secreted
- what does it inhibit
- how is it linked to SAD
It is secreted from the pineal gland, at the base of the brain. The pineal gland receives information from the eyes and other sense organs about light and temperature levels. The pineal gland secretes melatonin during darkness but not during light.
One of the major functions of melatonin is to communicate with the pituitary gland in order to inhibit the secretion of many other hormones that relate to states of wakefulness.
It is thought that seasonal affective disorder (SAD) relates to melatonin levels. SAD often occurs at the beginning and end of winter, in countries where there are very short winter days, this reduced exposure to day light may lead to increased levels of melatonin.
What is oxytocin?
- where is it secreted
- what is it linked to
secreted by the hypothalamus and is released into the bloodstream via the pituitary gland or into the brain and spinal cord where it binds to oxytocin receptors. Oxytocin acts primarily as a neurotransmitter in the brain.
Oxytocin has been linked to trusting other people. Experimental manipulation of oxytocin levels have shown an increase in trust.
Changes in light and melatonin levels
- what happens as light decreases
- how does this affect the body
As natural light decreases and it gets darker and colder, more melatonin is released from the pituitary gland into the blood stream. This makes the body start to shut down, making us feel tired. It is thought that seasonal affective disorder and jet lag are linked to melatonin levels.
Supporting research: Avery et al (2001)
Use: this research suggests that the environmental factor of light has an affect on the physiological process on the release of the hormone melatonin. When there is more light, less melatonin is released.
Evaluate: used three different groups including a control group which means that results can be compared. However, they also used self-reports which aren’t objective.
Effect of navigational training on the hippocampus
- the idea that…
- what happens because of environmental demands
This is the idea that, although localization of function occurs, the specific location of a function is not necessarily fixed for everybody, and areas of the brain dedicated to certain functions, can be redistributed according to environmental demands.
Supporting research: Maguire et al (2000)
Use: research suggests that the continuous use of an environmental stimulus leads to neuroplasticity when the use of one area of the brain is increased, this area increases in volume. With the taxi drivers, the environmental factor of an increased use of spatial memory, which is localised to the hippocampus, lead to an increase in the volume of the hippocampus.
What are the implications of lifelong neuroplasticity?
- illnesses
- negative life events
- Illnesses that may have been seen as incurable in the past may now be able to be cured. This can be suggested as the idea of neuroplasticity is that the brain changes and so with the right environment it may be possible to change the brain for the better and cure illnesses.
- This can also be linked to the idea that the neural impact of negative life events can be reversed eg Romanian orphans.- the environment can encourage the negative to be reversed.
Examine one interaction between cognitions and physiology in terms of behaviour. Evaluate two relevant studies.
- How damage to hippocampus can cause memory impairment.
- Two case studies: Clive Wearing and H.M.
Clive use: shows clear interaction between damage to the hippocampus and memory. Once his hippocampus was damage he couldn’t consolidate or store new memories.
H.M use: shows the interaction between the hippocampus and memory, how the hippocampus is important in memory processing and storage of new memories. Indicated that the hippocampus in a temporary store rather than permanent.