Neuropsychology

DEVELOP AN UNDERSTANDING OF BRAIN DAMAGE

Those of us with healthy brains work our way through life doing things we have learnt and learning new things all the time. How would you feel if you were no longer able to do this? Many people experience cognitive difficulties due to disease, brain damage or the onset of a mental health problem and life can become incredibly challenging for them. This course looks at how impairments can manifest through behaviour and thinking when the nervous system is compromised.   

EXPAND YOUR SKILL SET

Neuropsychology is the area of psychology that studies brain-damaged patients to understand the workings of our brain. Our brain is constructed of two hemispheres which are responsible for different facets of human personality and behaviour. Despite some essential differences in some functions, these hemispheres communicate through inter-hemispheric neural connections, mostly through the corpus callosum. This communication allows the brain to integrate different elements to produce coordinated, apparently seamless action and a unified personality.

Neuropsychology is an interdisciplinary subject, a mixture of psychology and neuroscience. It aims to understand how the function and structure of the brain relates to human and animal behaviour and psychological processes. Neuropsychology uses scientific methods and in common with cognitive psychology and cognitive science, it shares the information processing view of the mind. 

Study this course to develop your understanding of the way a person’s behaviour, personality and thought processes are affected by neurobiological processes, as well as the changes that can occur due to damage of the brain.

Lesson Structure

There are 10 lessons in this course:

1. Foundations of Neuropsychology
   • What is neuropsychology?
   • The Information Processing Approach
   • Studying the human mind
   • Techniques used
   • Brain scans
   • Animal studies
   • Methods of investigating the brain
   • Psychological tests
   • Stroop test.
2. Neurophysiology
   • Neurons
   • Parts of a neuron
   • Neurotransmitters
   • Effects of neurotransmitters
   • Neurotransmitters and their effects
   • Endorphins
   • Disorders associated with neurotransmitters
   • Glia cells
   • Schwann cells
   • Nerve impulse
   • Synaptic transmission
   • Nerve impulse
   • Neuromuscular transmission.
3. Neuroanatomy
   • The nervous system
   • Parts of the central nervous system
   • The brain
   • The spinal cord
   • Spinal nerves
   • Blood brain barrier
   • Peripheral nervous system
   • Autonomic nervous system
   • Sensory somatic nervous system
   • Spinal nerves
   • Cranial nerves
   • How the nervous system works (a summary)
   • Problems with brain functioning
   • Cerebral palsy
   • Brain tumours
   • Injuries to the head
   • Epilepsy
   • Headaches
   • Mental illness
   • Meningitis and encephalitis.
4. Laterality and Callosal Syndromes
   • Brain lateralisation
   • Left handedness
   • Cognitive neuropsychology
   • Callosal syndrome
   • Complete severance
   • Split brain
   • Complete severance
   • Split brain syndrome
   • Lobotomy
   • Psychosurgery
   • Dual brain theory
5. Cognition, Personality and Emotion
   • Brain damage
   • Emotion and moods
   • Phineas Gage
   • Brain damage and emotion
   • Frontal lobe
   • Higher level functioning
   • The Limbic system
   • Neurotransmitters
   • Neuropsychology
   • Emotions research.
6. Perception Disorders
   • Hemispatial neglect
   • Causes of hemispatial neglect
   • Auditory perceptual disorder
   • Agnosia
   • Visual agnosia
   • Types of visual agnosia
   • Prosopagnosia
   • Simultanagnosia
   • Optic aphasia
   • Hallucinogen persisting perception disorder.
7. Motor Disorders
   • Parkinson’s Disease
   • Motor disorders resulting from traumatic brain injury
   • Non traumatic and/or genetic paediatric movement disorders
   • Cerebral palsy
   • Motor conditions
   • Gerstmann’s Syndrome
   • Apraxia
   • Motor skills disorder
   • Motion dyspraxia
   • Neural transplants and Parkinson’s Disease
   • Gene therapy
   • How does gene therapy work
   • Ethical issues surrounding gene therapy,
8. Language
   • Broca’s area
   • Wernicke’s area
   • Speech
   • Language
   • Speech and language disorders
   • Apraxia
   • Aphasia
   • Stuttering
   • Neurogenic stuttering
   • Troyer syndrome
   • Speech disorders.
9. Dementia
   • Kinds of dementia
   • Alzheimer’s Disease
   • Vascular Dementia
   • Multi-infarct Dementia
   • Parkinson’s Disease
   • Pick’s Disease
   • Dementia with Lewy Bodies
   • Huntingdon’s Disease
   • Pseudo-Dementia
   • Spotting dementia and other conditions,
10. Neurodevelopment
    • Major processes of neurodevelopment
    • Neurogenesis
    • Migration
    • Differentiation
    • Apoptosis
    • Aborisation
    • Synaptogenesis
    • Asperger Syndrome
    • Neuroplasticity and brain damage.

Each lesson culminates in an assignment which is submitted to the school, marked by the school's tutors and returned to you with any relevant suggestions, comments, and if necessary, extra reading.

Aims

• Describe the relevance of neuropsychology to managing psychological disorders.
• Explain the physiology of the nervous system.
• Describe the anatomy of the nervous system.
• Describe how conditions within the brain affect the way in which a person is physically capable or incapable of performing a variety of different tasks.
• Explain how various aspects of a person’s thought processes may vary according to that person’s neurobiology.
• Describe a variety of perceptual disorders.
• Explain a variety of motor disorders.
• Explain the neuropsychology of language.
• Differentiate between different dementias.
• Explain aspects of development in neuropsychological terms.

What You Will Do

• Learn about the development of Neuropsychology and techniques used in human neuropsychological studies.
• Describe the Neuroanatomy of the: brainstem, cerebellum and cerebral cortex, organisation of the cerebral cortex, cranial nerves, brain covering, ventricular system, arteries, brain malfunction, visual system and other systems;
• Determine why there is laterality;
• Discuss callosal syndrome;
• Discuss and compare theories of frontal lobe function;
• Contrast normal aspects and abnormal aspects of emotion from a neuropsychological perspective;
• Develop a diagnostic table of perceptual disorders;
• Determine how the brain perceives faces;
• Discuss language formation;
• Describe language disorders;
• Develop a table of kind of dementia;
• Learn how recovery of function is affected across age spans.

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START WITH A BETTER UNDERSTANDING OF THE NERVOUS SYSTEM

The nervous system allows humans to adapt to changes. Changes can occur inside (e.g. too little oxygen while running) or outside (e.g. the anticipation of food or the chill of a winter wind). The nervous system will perceive the change and will take actions to adjust to it. The nervous system is rather like the lookout on a riverboat; it monitors conditions and gives warnings when something unusual or dangerous is ahead. Once the warning is received, the body is able to take steps to avoid or correct the situation. The nervous system has to be highly complex to be able to perform such sophisticated services.

Until the late 1800’s, scientists did not know if the nervous system was made up vast networks of connected nerve cells, or whether the cells were separate. We now know that they are, and that they carry out their enormous task of keeping the body alive and functioning, and our minds working, by means of chains of action. The human brain is estimated to have around 100 billion nerve cells working to help create apparently seamless and integrated action, thought, and body function. To understand how they interact, we must learn about their individual structure and behaviours.

NEURONS

The nervous system contains two kinds of cells: neurons, which receive and transmit messages, and glia, which help maintain neurons and facilitate their functioning.

The cell body or soma is the place in the neuron where major metabolic activity occurs, as it does in all animal cells. The soma of a neuron is enclosed in a plasma membrane that separates the cell from its environment. Water, oxygen and carbon dioxide can move through the membrane, and certain ions (atoms with a positive or negative charge), such as calcium, potassium, and sodium, can pass through the membrane in special channels.

The membrane also encloses a fluid called cytoplasm, within which float all the structures essential to the proper functioning of the cell. These structures, called organelles, have specific functions, and include:  

• A nucleus (lacking in red blood cells), which contains chromatin (active DNA) and a nucleolus (formed from chromatin) that produces ribosomes;
• Ribosomes, where the cell builds the protein it needs;
• Mitochondria, where energy is produced for all the cell’s activities;
• Endoplasmic reticulum, a network of tubes that moves proteins to different parts of the cell;
• Lysosomes, which recycle cell material and repair the plasma membrane; and
• The Golgi complex, a network of sacs that stores hormones for secretion by the cell.
  
  

Neurons can be divided according to function (which also affects their structure), into:

Sensory Neurons

These register stimuli, and are specialised to register only particular kinds of stimuli, such as touch or smell, to the central nervous system, which interprets the message as pain, heat, redness etc. The impulse in a sensory neuron begins in the nerve ends then travels along the dendron to the cell body. The impulse then passes through the axon to the next sensory neuron on its way to the central nervous system.

Motor Neurons

Messages are sent from the central nervous system to muscle or gland cells, stimulating them to take appropriate action, such as contracting, or withdrawing from the source of pain. Again, the stimulus passes through the dendrites into the cell body, then to the axon to the next motor neuron. The stimulus is finally received by motor end plates which are embedded in a muscle and cause the muscle to act, or by receptors in the gland.

This means that sensory neurons conduct impulses towards the central nervous system while motor neurons conduct impulses away. Sensory neurons are sometimes referred to as receptors (because they receive the stimulus) while motor neurons can be termed effectors (because they effect a change).

Parts of a Neuron

Nerve cells contain the same elements as all animal cells. However, most also have some elements distinctive to them: dendrites, and axon, and presynaptic terminals. The cell body (orsoma) and the dendrites of many neurons are also covered with synapses. The actual shape and structure of a nerve, however, is largely dependent on its function, and the number of other nerves to which it is connected. Some nerves have very few connections to other nerves, while others are parts of large networks. (Remember, though, that by ‘connected’, we do not mean physical connection but close interaction. Nerves cells are separate, even though many of them form long chains running through the body.

Dendrites

Neurons receive stimulation (sometimes called excitation or more simply, a message) from other nerves or the environment through their dendrites. Dendrites are the information receiving part of the neuron (Bodian, 1962), and are fibres that extend from the soma or cell body. Their name ‘dendrites’ comes from the Greek ‘tree’, because of their branching appearance.

Not all dendrites look the same. Dendrites of different neurons can look quite different, perhaps reflecting their different functions within their network. Some have only a few dendrites, some, a whole bush of them. Some dendrites are long and thin, others are thicker, with many more branches, or fairly short, depending on how they contribute to the surrounding network of neurons.

The surface of a dendrite is lined with receptors through which the dendrite receives messages from other neurons. Therefore, dendrites with greater surface area are able to receive more information. In this way, a single dendrite can receive thousands of messages from other neurons.

The dendrites of certain neurons also carry small growths or spines that greatly increase their surface area and allow them to receive specialised information. However, dendrites do not just receive information and pass it to the soma and axon; they apparently also play a role in shaping and integrating that information.

The dendritic branching of a neuron can grow or retract in the developed nervous system, allowing the nervous system to respond to environmental and other factors. A stimulating environment seems to be associated with growth of dendrites, whereas senility, alcohol and age can result in shorter and few dendritic branches.

Axon

An axon is a thin fibre that is usually longer than dendrites, along which an impulse is sent from the nerve body to other neurons, a muscle or a gland. A neuron has one axon, though it may have branches some distance from the cell body, and some axons are very long. Some are around a meter long, extending from the spinal column to the feet. Not all neurons have an axon, though. Some neurons transmit messages only to immediately adjacent neurons, and do not therefore require an axon; these are called local neurons.

Synapse

The synapse is the point at which communication occurs between two neurons or a neuron and a muscle or gland. Each axon and axon branch swells at the tip, where it releases the chemicals that either excite or inhibit the next neuron. At this tip, the axon swells into a bulb called a presynaptic terminal. The end of the axon receiving the message is called the postsynaptic terminal. The actual space between this terminal and the next neuron, muscle or gland cell is called the synaptic cleft, across which an impulse is transmitted electrically, but mostly, through chemical action. (See neurotransmitters, below). Because of the work involved in this chemical action, the terminal contains many energy-producing mitochondria.

Although axons are called the information-senders of the neuron, sending messages away from the soma, each axon also carries information from another structure towards the soma. As messages pass from neuron to neuron, a single neuron in the chain both receives and transmits messages. Therefore, an axon that brings a message to (is afferent to) one part of the brain might transmit that message from (efferent to) a gland. An intrinsic neuron is one that transmits messages within a single structure.

Myelin heath

In vertebrate physiology, many axons are covered with a myelin sheath made of fatty cells. The autonomic nervous system usually does not contain myelin sheaths. Myelin sheaths insulate the axon from electrical activity, which allows signals to be transmitted at a faster rate. It is not a continuous covering, for the cells are separated by gaps called nodes of Ranvier. Since fat is a good insulator, the myelin sheath speeds the transmission of an electrical impulse so that it jumps from one node to the next in a process called saltatory conduction. This rapid relay-type of transmission of impulses permits faster, coordinated responses to stimuli. Another benefit of saltatory conduction is that it conserves energy. The effects of destruction or loss of parts of the myelin sheath will depend on the functions of the affected neurons.

To summarise:

• Axon is a long extension of a neuron, carrying nerve impulses away from the cell body.
• Cell body is a cell body of the neuron, containing the nucleus (soma)
• Axon terminals are hair like ends of axon
• Myelin sheath is a fatty substance surrounding and protecting nerve fibres
• Dendrites are a branch structure of the neurons receiving messages, which are attached to cell body
• Node of Ranvier, one of the gaps in the myelin sheath, where the action potential occurs during salutatory conduction along axon
• Schwann’s Cells are cells that produce myelin, located within myelin sheath
• Nucleus is an organelle in the cell body of the neuron, containing the genetic material of the cell.

Benefits of Studying This Course

Neuropsychology is a specialist area of psychology. It is relevant to people who seek a more in-depth understanding of the brain and how damage through congenital conditions, injury, disease or disorders can affect its functioning and behaviour. It is assumed that people opting to take this course have some basic understanding of the brain's anatomy as well as reasonable knowledge of human biology.  The course doesn't cover how to undertake psychological testing of neuropsychological problems but it does provide students with a solid grounding in brain dysfunctions.
 
This course will mainly appeal to people working in, or wishing to work in: 

• Psychology
• Psychotherapy
• Biological sciences
• Health sciences
• Psychiatric nursing
• Health professionals
• Teaching
• Research