The role of the brain Flashcards
Describe phrenology as an early brain investigation technique.
Developed by Franz Gall, phrenology is the study of the shape, size and geography of a skull to determine information about the mental capacity of a person. This technique was used as a baseless hypothesis for the inferiority of non-white people.
Identify brain imaging techniques and explain how they can be used to help understand the brain-behaviour relationships.
Neuroimaging techniques allow scientists to see blood flow and chemical reactions inside the brain in an attempt to understand why people act in certain ways. The electroencephalogram (EEG), for example, records electrical activity in the brain in the form of brainwaves. This is particularly important when studying consciousness and sleep but is unable to show specific location of activity.
A positron emission tomography (PET) scan, however, measures volume and location of blood flow by tracking radioactive substance. This allows the scientists to see the location of action in the brain, and also mental state as any disease progresses. Although, this is an expensive scan, which has radiation injected and only has a short time period.
Other scans are mainly used to show an image of the brain but are usually low resolution and are only used to look at shape of the brain.
Recognise the basic function of the central nervous system.
The central nervous system consists of:
- the midbrain (centre) : coordinates movement, sleep and arousal.
- the forebrain (exterior) : responsible for recieving and processing sensory information and for higher order thinking processes (problem solving, planning, memory, language and emotions)
- the hindbrain (closest to the spinal cord) : links to the spinal cord and the rest of the brain. It is important for movement and balance.
- spinal cord : a connection between the brain and the rest of the body (peripheral nervous system)
Reognise the basic function of the peripheral nervous system.
The peripheral nervous system is composed of all the nerves and ganglia outside the brain and spinal cord. This works with the central nervous system to enable interactions with the environment. It contains the somatic and autonomic peripheral nervous systems.
The somatic nervous system contains sensory and motor nerves. Sensory nerves control impulses from the body to the central nervous system. The motor nerves control impulses from the central nervous system to organs.
The autonomic nervous system is responsible for communication between the body’s non-skeletal muscles and the internal organs and glands that carry out bodily functions. This system cannot be controlled. Within this part of the system, there are the sympathetic nervous system and parasympathetic nervous system. The sympathetic system is an emergency system that prepares the body for action, activating during a threat. The parasympathetic system controls the freeze response, activated when running isn’t an option. It is also responsible for homeostasis, maintaining internal balance.
Construct a diagram of a neuron.
See notebook for diagram.
Distinguish between sensory, motor and interneurons.
Sensory neurons carry sensory information from body or outside world to CNS while the motor neurons communicate messages from CNS to particular muscles. Interneurons transmit information between motor and sensory neurons.
What are the different areas of the brain?
The different areas of the brain are the forebrain, midbrain and hindbrain. The forebrain as the exterior receives and processes sensory information and is responsible for higher order thinking, like emotions, problem solving and memory. The midbrain is in the centre, which coordinates movement, sleep and arousal. The hindbrain is located next to the spinal cord and is important for balance.
Broca’s area is located in the left frontal lobe, and is the speech production centre. Wernicke’s area is in the left temporal lobe, and is the language reception and interpretation area. It also includes the creation of grammatically correct speech. Geschwind’s territory provides a connection between these.
