Guest Post: EEG, Eye-Tracking, and Evaluation: Finding a way into Psychology

Last week, Lora, a student from Year 12 at a local sixth form, visited me in the Department. I asked her to blog about her experiences. This is what she said:

I decided to search for work experience in Psychology because it is a new and exciting subject for me that I have found extremely interesting to study throughout my first year of Sixth Form. I am also considering taking on Psychology at university next year, so I felt that this experience would be valuable.

Monday

Today was my first day and I had a mixture of nerves and excitement, the latter proving more dominant. After asking several people how to find my way to the correct building, floor and office, I was successfully directed to Siân. Once there I: introduced myself, was given my very own work-space (a whole room in fact) and was shown the rest of the department.

My first task of the day involved 48 questionnaires for a visit to school tomorrow. I had to fold, staple, sort and proof-read (correcting any errors I found) . Two of the piles did not have a specified condition on the front, so Sian gave me the job of working this out. Now, I hadn’t finished quite yet as I needed to have two piles (one male, one female) of questionnaires and they needed to be randomly sorted. Another task I had to do was create an Excel document and write out all the questions. Not such a mammoth task seeing as the questions were the same. Accomplishment – a feeling which was felt on numerous occasions throughout the week.

Other things I got out of the day involved: reading social development papers, obtaining two massive, free text-books, because there was a departmental book clear-out, and beginning to use and get to know the statistics program SPSS. Nice people, a nice subject and free resources to keep – what a nice way to start off the week.

Tuesday

child school

Image from brookes.ac.uk/psychology

This morning I continued to help Siân input data she had collected the previous week into SPSS. Fortunately, we managed to finish this before we set off to collect more data. The primary school may have been local, but the commute took us about one hour. We arrived in plenty of time so that we could set up in ease and I could be given instructions on what I was to do. The children filled out the questionnaires very quietly and the school made us feel welcome. In my opinion, the classtime and the day were successful.

Wednesday

eyetrackThe day that Siân and I managed to input all of the data from the previous day into SPSS –accomplishment, once again. After this I was lucky enough to participate in an experiment for a postgraduate student’s research project. The experiment involved a structured interview, filling out questionnaires and then several stages of activities. The project focused on the link between ‘Eye Contact and Social Anxiety’, (i.e. some research suggests that people with high levels of social anxiety make less direct eye contact than people without social anxiety).

Later on in the day I attended a departmental seminar which took form of an IT workshop on Open Access and the REF. If I have to be honest, all the information didn’t really make sense to me because it was something I had never come across. So, halfway through, I migrated to reading Siân’s online blog. And here you are reading my first piece which has been published online.

My final job of the day was to make a start on sorting out a massive pile of evaluation forms from the Friendship Workshops that Siân had conducted in 2014 and 2015 so that they were ready for data input.

Thursday

On Thursday morning I attended Siân’s “Shut Up and Write” session. This session is a great way to be productive by just sitting down and getting on with your work, in silence. I occupied myself in drafting a Methods section for the research we did in school on Tuesday. Siân was kind enough to lend me her PhD for the session so that I was able to use the method section as a template. I was also given a whistle-stop tour on how to use SPSS to  get basic statistics. We were particularly interested in the means, standard deviations, and correlations.

Moreover, we had lunch with Sarah and several other colleagues from the Psychology Department – everyone was really friendly. And for the rest of the day I continued work on the hundreds and hundreds of evaluation forms, and I managed to finish this job! Need I say the feeling again? (Hint: the word begins with an A.)

Friday

Image from brookes.ac.uk/psychology

Image from brookes.ac.uk/psychology

My last day. The week has flown by. But as idioms go, time flies when you’re having fun. A good sign, surely. And I will be back again at the end of next week with my school in order to attend the Psychology conference. They haven’t got rid of me that fast!

So, for my last day, as Sian was away at a conference, I was cared for by the lovely Sarah and met even more colleagues. I was able to write this blog piece, do some transcribing and visit the EEG lab. Transcription consumes a lot time. One has to listen to the audio file, type what each speaker is saying, listen carefully to understand what they are saying and do this hundreds and hundreds of times. I had a go at one today and I didn’t even get through the full file. The interview was about 35 minutes long and I only got through 10 minutes! I guess it’s not too bad for my first go, but I didn’t get that full accomplishment feeling…

EEG stands for electroencephalogram. It is where the brain’s activity is recorded to help diagnose or manage certain conditions. Brian cells continuously send one another messages and signals that can be picked up as small electrical impulses from the scalp. This process of picking up and recording the impulses is known as an EEG. I was shown the swimming-hat-net-like-cap, made up of electrodes, which a participant would wear. Apparently, baby shampoo is put on the participant’s scalp in order to aid conductivity. How bizarre. However, the procedure is painless and the participant should feel comfortable throughout.

Overall, this week has been a valuable experience that I’m sure I will never forget. I really do appreciate everything that was done for me. The week has shown me the opportunities that await me and things I could be doing in future. For anyone reading this that enjoys Psychology and is considering the subject, I highly recommend doing work experience in this field. So that’s it for this blog piece. I hope it has been as successful as my week…

Very well-accomplished, blog-post, Lora – you’d make an excellent blogger in Psychology, if you fancy that later on…. I should also say that Lora was fantastically helpful to me in getting us ready for school, remembering things when we were at school, and in dealing with the aftermath of the visit. She also reminded me why I love working in Psychology so much. Here’s to the next generation of students …

PowerPoint: In Memorium?

pptLast weekend, a world-renowned University of Oxford professor stunned me when he told me he had never used PowerPoint. Realizing that small group teaching is at the heart of Oxford University’s pedagogical approach, I could see that it might not be necessary here – but not to have used it ever? What about conference presentations? Open days? In stark contrast, a quick straw poll of our MSc in Psychology cohort for this year has just revealed that they have never had a teaching session without  PowerPoint or Prezi. I know that all of the seminar speakers visiting our Department this year have also used this technology in their talks. In light of this dichotomy, I am dedicating this blog post to thinking about the use of PowerPoint* in teaching at university.

Initially, the emerging literature on PowerPoint was glowing. Researchers noted that when there was variety in the slides presented (Clark, 2010) and relevant text and images were presented (Bartsch & Cobern, 2003) PowerPoint could be an effective learning tool. With regards to Psychology, Erwin and Rieppi (1999) compared the effectiveness of multimedia and traditional classes. It was found that students in the larger multimedia class averaged higher grades than those in the traditional classes.

However, other research showed that the relative benefits of PowerPoint over the more traditional “chalk and talk” lecture might be illusory. For example, Savoy et al. (2009) showed that students preferred PowerPoint presentations, but retained 15% less information from such lectures. Relatedly, Amare (2006) assessed students’ written performance, after delivery  using PowerPoint versus traditional lecture, and found better performance with traditional lectures.

Of course, when it comes to such research it can get quite messy. Neither the assignment of students to lectures versus seminars, nor the group size were controlled for in Erwin and Rieppi’s paper and in Amare’s study traditional lectures were accompanied with handouts, whereas the PowerPoint lecture was not. The controls in each study (and many others) were wildly different from one another. Thus the jury is out when it comes to the effectiveness of PowerPoint over other teaching methods.

That aside, it remained troubling to my mind  that while some lecturers did not use PowerPoint at all, some cohorts of students apparently receive very little but instruction by PowerPoint, at least as far as group teaching sessions are concerned. So, it was a surprise when I attended the Brookes Learning and Teaching Conference 2015 #bltc15 yesterday, and was met with – almost no PowerPoint. The closest I got was an image of an umbrella – and a list of discussion questions.

wide_lane

So what happened instead? Well, the first session was led by @georgeroberts as a “walk and talk”. We took to a lane behind the university campus as a group, and ambled along it, taking it in turns to talk to the topic of inclusivity in education. In other words, we thought about inclusion in the classroom, outside the classroom – and perhaps, as a result, outside the box. For what it is worth, participants felt that their ideas flowed more freely in this setting, and it’s certainly one I would like to add to my arsenal for my next seminar (British weather permitting….).

Next was Isis Brook’s keynote, also delivered without PowerPoint. One of my colleagues admitted to being perturbed by this. I will admit to finding it more difficult to concentrate on what was said, without visual clues if my mind wandered. But – the session was far from dydadic –  questions were asked about our own experiences for intermittent discussion with colleagues.

cliffordThe afternoon gave way to further discussion about culture shock and mental health in international students, and included a guest appearance from Clifford the Elephant (the elephant in the room who visits events to open up conversations about mental health). To be more specific then, the afternoon was spent listening to students’ experiences (sans computer), to playing a game of human diversity bingo and to (re-) meeting Clifford and the issues he represents. Barely a slide was in sight.

So we come to today. Which must be these MSc students’ first experience of a large class teaching session without PowerPoint. We’re running a “shut up and write” group, to help them with their assignment motivation. On balance, as a participant and a teacher, I think I prefer teaching methods that don’t involve PowerPoint …I’m about to find out what my students think of it all. …

*Other presentation software is available.

The Right Way To Do Statistics in Psychology

It’s that time of the year again. The time when undergraduate students in Psychology have collected their data, and are furiously trying to get it analyzed and written up, in time for their dissertation deadline.  It’s also the time of year when students tend to panic about the “right” way to analyze their data. But – as far as statistics go – there is no single right way to go about things. In fact, there is as much debate about doing statistics in Psychology as there is about psychological theories themselves – with whole journals dedicated to the topic. When it comes to dissertation stats, there is no single right way here, either…I explain.

I have one manipulated variable (call it Experimental Condition) and two continuous variables that I measured, Measure A, and Measure B. I want to know how Measure A and Experimental Condition interplay to influence Measure B. I have met all the assumptions for parametric data analysis. Although that research question is clearly defined, there are still several ways I could go about this.

Option 1

One way would be to perform a linear regression, entering Experimental Condition as a dummy variable and Measure A (centered about the mean) as predictors of my outcome, Measure B. If I found any interaction, I could analyse it using a simple slopes analysis. That would answer my research question.

Option 2

Equally viable, however, would be to run this analysis using ANOVA – because the maths underlying ANOVA and regression analyses are essentially the same. You can check this for yourself, by running the two analyses on the same variables: you will find that because both rely on what is called the General Linear Model the R squared value is the same for each. The distinction between the two in teaching terms is really just an historical artefact arising because ANOVA has been traditionally used for experimental designs and regression for correlational designs. It doesn’t have to be that way: whether the analysis you do make any sense depends on what you were trying to find out, more than anything.

Anyway – if I ran this analysis using ANOVA, there are two ways I could go about it. I could continue to treat measure A as a continuous variable and, in SPSS at least, force the program, via the syntax editor, to treat measure A as continuous but nevertheless a bona fide fixed factor, by adding it after the WITH sub-command:

UNIANOVA
Measure_B  BY Experimental Condition with Measure A_centred

Option 2a

I could, however, legitimately perform a median split on Measure A, creating a new variable where people are coded as either high A-scorers or low A-scorers. I would then enter Measure A _ split into the ANOVA alongside Experimental Condition, as above.

In either case, if I found an interaction between Measure A and Experimental Condition, I would analyse it using a simple effects analysis (to look at the effect of Experimental Condition at differing scores on Measure A).

The Right Way?

So – either ANOVAs or regression could be used for the above research question. Neither way is “wrong” although statisticians will point out the advantages and disadvantages to each approach. The classic disadvantage to median splits, for example, is that I would lose some of the variance provided in the variable scores (because I have changed a continuous variable to a dichotomous one).

Of course, that said, there are some things that we need to do, for any of the above options to be “right” before we run those tests. Here is a checklist, courtesy of Tabachnik and Fiddell (2007) – with the health warning that, the debate around statistics rages on, and these are guidelines – one high-profile  journal in Psychology decided earlier this week that reporting p values is inappropriate full-stop….

(1) Before you do anything, check for missing values and cases where weird stuff seems to be happening. Work out what is weird, and consider deletion of these cases, or checking against the questionnaires for human error in data entry.

(2) Check you meet the assumptions for the tests you want to do. See Tabachnik and Fiddell (2007) for myriad guidelines on what to do with the data, if you fail to meet an assumption.

jf16(3) This is not a fishing expedition. Define your research question clearly, and the type of test(s) you need to do to answer it with your data. Report what you find.

(4) If you do perform extra post-hoc tests, because something interesting has come up, don’t be afraid to admit to that. There are ways of statistically adjusting for the probability of finding significant results in such cases, and the important thing is being transparent about what we are doing as scientists, to allow effective evaluation of findings.

So – to sum this up, before you do anything with your data, look at it. Is it weird? Is it normal(ly distributed)? Can you use parametric statistics or not? Then, work out what research question you would like to answer, and what types of variable you now have. Based on this, choose among the options for answering that research question. All the time, remember to be transparent about the analysis and post-hoc tests that you are using. Just as one rationalizes the inclusion of different variables in your study in the Introduction, the Results section should give a rationale for what you have done with each variable, why, and what was found. Statistics in Psychology is about having a rationale, rather than a “right” answer.