Some statistics

Last week we covered a fairly exciting section of the research methods specification - measures of dispersion and measures of central tendency. You need to know:

• How to calculate the mean, mode & median
• When it is appropriate to use each - ie the mean is affected by extreme scores so it might be best to use the median when you have lots of these, and the mode is best used for nominal (categoric) data
• How to calculate the range and when to use it
• What the standard deviation is and when to use it. You don't need to do the maths here but the standard deviation is a measure of the spread of the data around the mean.

This is all well covered in your textbook so do make your own notes as well.

Eyewitness testimony

Can we trust our memory? If you witnessed a crime, would your memory of it stand up in court? We are going to look at an area of memory research that has influenced legal practice. The experiments of Elizabeth Loftus and her colleagues were key in showing how unreliable eyewitness testimony can be.

Today's powerpoint is here.

You need to make your own notes on Loftus (1975), using your textbook.

Work for Mr Lawrence - Tuesday 22nd November

I'm recovering from a virus and not in school today.

We will have a short test on Thursday on the four models of abnormality so revise these, looking particularly at the cognitive model which we spent least time on in class.

For this lesson's work, read and make notes on Psychoanalysis, the therapy based on the Psychodynamic approach. Don't confuse this with the term 'psychotherapy' which is any psychological therapy - that is, anything not biological. In particular make sure you have notes explaining the following key terms:

• Insight
• Free association
• Manifest content (of a dream)
• Latent content (of a dream)
• Projective test (e.g. Rorschach ink blots)

When evaluating a therapy we need to consider its efficacy (how effective it is), how well it works for different disorders and for different types of people, how time-consuming and expensive it is and ethical issues. This is easier to do when we've looked at the therapies suggested by all the models, but have a read about this and we'll discuss on Thursday.

Psychodynamic, Behavioural and Cognitive models of Abnormality

Here are the presentations for the psychodynamic, behavioural and cognitive models. We spent some time in September looking at each of these approaches to psychology in general. For your exam you need to describe them as 'models of abnormality' - that is, general theories/explanations - key assumptions about the causes of abnormality and general strengths and weaknesses of their explanations.

It's very useful, but not essential, to know how each model explains one or two specific disorders - we've talked about schizophrenia (best explained biologically), depression (biological and cognitive) and phobias (behavioural).

Here is a documentary on Freud which is useful for evaluation of his theory - remember that there are more modern psychodynamic explanations too, with less focus on early childhood and sex.

Here is your essay for submission through Edmodo by Thursday 24th November.
a) Describe the behavioural and cognitive models of abnormality. 12 marks AO1
b) Compare and contrast these models – which provides the more useful explanation of abnormality? 12 marks AO2

We discussed the three components of the working memory model - the central executive, phonological loop and visuospatial sketchpad. Next lesson we'll look at some of the supporting evidence. Today's powerpoint is here.

You also started your miniprojects - Does the word length disappear when participants are given an articulatory suppression task?

The write-up guidance sheet is here. The completed project must be handed in on Tuesday 22nd November.

The use and abuse of student participants

We've discussed recently how the classic STM experiments (Peterson & Peterson, Baddeley (1966) etc) might be lacking in population validity - they tend to use university students as participants as these are readily available. This is widespread in experimental psychology, and psychology students often have to take part in research to gain course credit.

Here is an interesting article investigating the ethics & practical issues involved in using student participants.

The Biological Model of Abnormality

Yesterday we began to look at different models of abnormality. A model in this sense is a general theory or explanation - a set of assumptions and ideas about the causes of abnormality in this case. We will return to each of the approaches we covered at the start of the course (psychodynamic, behavioural and cognitive) to look in more depth at how they explain abnormal behaviour, and how they propose it should be dealt with.

To revise the key ideas of the approaches we looked at various explanations for the eating disorder Anorexia Nervosa. You don't need to know about any specific psychological disorders for your exam, but it's useful to know examples to extend your answers. Here are the cards we used in the lesson.

The biological model assumes that psychological disorders have physical causes in the brain - these may be genetic in origin, or be caused by infection. The structure of the brain (neuroanatomy) may be changed, or the balance of neurotransmitter chemicals (brain biochemistry) may be the problem.

Here is the presentation from the lesson.

Homeword for Tuesday 8th November is to complete notes on the Biological Model using your textbook, and focusing on its strengths and limitations. A list of points to use:
 
Successful explanation of general paresis (insanity caused by syphilis bacteria)?

• Humane or inhumane?
• Cause or effect?
• Objective, scientific evidence?
• Inconclusive evidence?
• Diathesis-Stress? - We will spend some time on this last one next week.