Psychology AOS 2 SAC

Magnetic resonance imaging (MRI)

Magnetic resonance imaging (MRI)

Uses magnetic fields to vibrate atoms in the brain’s neurons and generate a computer image of the brain, can produce in-colour and clearer pictures than CT (structural imaging)

Computerised tomography (CT)

Uses x-ray equipment to scan the brain at different angles and make a picture of the brain (structural neuroimaging)

Positron emission tomography (PET)

Uses a radioactive drug called a tracer to locate metabolic activity, produces 2D or 3D scans or brain structure, activity, and function (functional neuroimaging)

Functional magnetic resonance imagine (fMRI)

Detects and produces images of brain activity by measuring oxygen consumptions across the brain. The colour variations reflect the level of activity of brain areas while a participant engages in a task (functional neuroimaging)

Strengths and limitations of MRI

Good to investigate/diagnose conditions that affect soft tissue such as tumours or brain disorders, expensive and time consuming

Strengths and limitations of CT

Useful screening tool for detecting possible tumours or lesions within the abdomen, not very detailed images

Strengths and limitations of PET

Can assess cancers and brain and heart diseases, can give false results if chemical balances within the body are not normal.

Strengths and limitations of fMRI

Can be used to see how a normal, diseased or injured brain is working, or to assess the potential risks of other brain treatments, lack of precision and high cost

Hindbrain

Structures at the base of the brain including the cerebellum, medulla and pons, influences motor functions and autonomic responses such as breathing, heart rate, sleep and arousal

Midbrain

Connects upper and lower brain areas and houses structure involved with movement, processing of visual, auditory and tactile sensory information, sleep and arousal

Forebrain

A collection of upper level brain structures that include the hypothalamus, thalamus and cerebrum; involved in complex cognitive processes, emotion and personality

Cerebral Cortex

Outer layer of the brain involved in complex mental abilities, sensory processing and voluntary movements; roles in a diverse range of activities

Frontal lobe

Has a role in all our thinking, feeling and behaving, coordinates many of the functions of the other lobes and determines our responses.

Primary motor cortex

A strip of cortex at the back of each frontal lobe that initiates and controls voluntary movements

Primary somatosensory cortex

A strip of cortex located at the front of each parietal lobe that receives and processes sensory information from the skin and body parts

Temporal lobe

Located above and around the top of each ear, involved with auditory perception, memory, aspects of visual perception

Primary auditory cortex

Receives and processes sound from both ears

Occipital lobe

Almost exclusively devoted to the sense of vision, damage can produce serious visual impairments

Neuroplasticity

The brain’s ability to change structure due to experience, is more effective in younger people

Long-term potentiation

When synaptic connections are repeatedly activated, they become stronger, leading to long-term strengthening in those connections.

Long-term depression

Repeated low level of activation of synaptic connections makes them become weaker, which leads to elimination through synaptic pruning

Synaptic pruning

Where the brain removes neurons and synapses that it doesn’t need

Rerouting

Involves nearby neurons creating alternative neural pathways when existing connections are lost through injury

Sprouting

Involves existing neurons forming new axon terminals and dendrites to allow new connections to be made

Ways to maintain and maximise brain function

mental stimulation, diet, physical activity

Acquired brain injury (ABI)

Is damage to the brain which occurs after birth and is not related to a disease, can be sudden or insidious (prolonged), result in a change to the brain’s structure and activity

Examples of an acquired brain injury

Falls, sporting incidents, blows to the head, violent shaking, stroke, alcohol, drugs, lack of oxygen, brain surgery, infection, brain inflammation, epilepsy, degenerative brain disorders such as Parkinson’s and Alzheimer’s disease, motor neurone disease and CTE

Biological effects of ABI’s

Impaired sensory functioning such as loss of vision/hearing disturbances, muscle weaknesses, arthritis

Psychological effects of ABI’s

Poor attention and problem solving, reduced ability to plan and organise, and lack of initiative/motivation

Social affects of ABI’s

Impaired ability to communicate with others that can’t understand them, socially inappropriate behaviour, and difficulty following social rules

Chronic traumatic encephalopathy (CTE)

A progressive, brain degeneration and fatal condition thought to be caused by repeated blows to the head and repeated episodes of concussion

Case study

Small sample size, not a controlled experiment