Teaching synaptic transmission using ping pong balls

You will be clearing up ping-pong balls for days.

Many students seem to come to us with a block about bio-psychology. I’m not sure why this is but I suspect it’s got something to do with the English science curriculum, whose writers have apparently mistaken content load in the absence of conceptual coherence for academic rigour. But that’s an argument for another day and, probably, a different blog. The issue is, faced with content-load problems of our own, and in the face of students’ objections to learning ‘all that science stuff’ it’s easy for us to retreat into a ‘here it is, you’ve just got to memorise it’ teaching style.

And it is quite easy to teach things like synaptic transmission this way – all we have to do is drill the students with a series of steps, probably with accompanying diagrams. Provided, that is, we’re content to settle for teaching for knowledge, as opposed to teaching for understanding. Now, there are arguments for taking that approach: it’s quick, and if the assessment for which we’re preparing the students is recall based, it’s often good enough for the purpose of ‘getting the marks’ in an exam. However, if our values are oriented towards teaching as a way of changing students’ understanding of their world then it might strike you as unsatisfactory. And even if we’re not, recent changes to the A – Level psychology exams mean markedly increased demands on students’ capacity to think with content as opposed to just recalling it. There is strong justification, therefore, for teaching biopsychology in ways that move beyond the more presentation of information.

Over the past few years I’ve made increasing use of physical models to teach biopsychology. They make biological processes concrete for the students, who may find it difficult to visualise events at the microscopic level, and they reduce working memory load because having manipulable objects at hand makes fewer demands than maintaining mental representations of multiple concepts, especially when these are newly acquired and not well integrated with long term memory (there is some debate about this, but see Pouw et al, 2014).

Here’s an approach to teaching synaptic transmission that can be extended to a range of related areas including the mode of action of drugs and biological explanations of mental disorders. I’ve used it with groups of up to 20 or so students; more than that and it would probably be better to divide the group. You’re going to need lots of ping-pong balls. I bought a box of 500 from eBay for about a tenner.

  1. Prepare by inviting students to read about the process of synaptic transmission. This could be for a home learning task or in class using a reciprocal teaching routine. There’s a reading on synaptic transmission here that you can use or there are any number of web and textbook resources.
  2. Arrange your teaching space so there’s a large, clear floor area. Explain that we are going to deepen our understanding of synaptic transmission using the ping-pong balls. Tell the students that they should organise themselves to depict the process of synaptic transmission. The only rule is that each ping-pong ball represents one molecule of neurotransmitter.
  3. At this point, let the students sort themselves out and observe what they do. It is likely that they will arrive at an arrangement whereby one set of students is passing the balls to another set (or possibly throwing or rolling them). Whatever they do, it represents their shared conception of synaptic transmission, so it’s your starting point for developing that understanding further. At this point, pause proceedings and ask named students to explain how the model represents synaptic transmission.
  4. What follows is an iterative process of identifying shortcomings of the students’ model and inviting them to correct them. The ideas is that, with each iteration, the model becomes a more accurate representation and the students’ understanding correspondingly grows. For example:
  • ‘Vesicles can’t throw, and receptors can’t catch’, (addresses the misconception that neurotransmitter is ‘fired’ across the synaptic gap/aimed at the receptors rather than being a probabilistic process based on diffusion);
  • ‘I can’t see what’s causing the vesicles to release neurotransmitter’, (prompts the students to connect a change in neuronal firing rate with the release of neurotransmitter);
  • ‘All these receptors now have a molecule of neurotransmitter activating them – what problem do we have now?’ (introduces the idea that the neurotransmitter needs to be removed or the receptors will be permanently stimulated);
  • ‘There are no more ping-pong balls left in the box and loads in the synaptic gap’, (can lead to the importance of neurotransmitter concentration, the reuptake mechanism and the possibility of neurotransmitter depletion).

And so on. How far you take this depends on your inclination and the time available. I’ve found it’s usually possible to generate a model that includes the pre- and post-synaptic firing rate, vesicles, diffusion/concentration, receptors, enzymes that break down the neurotransmitter and the reuptake mechanism.

It is crucial that you keep questioning named students about the correspondences between different elements of the model and the process of synaptic transmission. The model doesn’t teach anything on its own; it’s a point of focus for the dialogue between you and the students.

A good way to finish the activity is with a free writing exercise in which students either describe the process of neural transmission from memory or write an explanation of how their model represents the process. This should be done from recall and allows them to consolidate understanding whilst giving you a chance of catching any remaining misconceptions.

Once you have established a viable model, you can use it in a number of ways. Simply recreating the model on a future occasion is a good revision activity, especially if done from free recall and if students are instructed to take on different roles from last time, so they have to co-construct their understanding again. You can use it to develop further understanding e.g. ‘what you have modelled is an excitatory synapse – how would things be different in an inhibitory synapse?’ You can also use it as a basis for teaching related ideas e.g. the effects of drugs e.g. ‘What would happen if we stopped the reuptake mechanism from working/what would happen if we blocked off these receptors?’ etc.

This approach is not without its risks. You may feel that you cannot rely on your students’ capacity to self-regulate during activities like this. That’s your call, but I would urge you to give it a go. You do need to be on the lookout for social loafing – some students may feel able to position themselves as an innocuous section of neural membrane and quietly opt out of proceedings. For this reason you need to keep up with the directed questions throughout. Finally, and most seriously, there is a possibility, when using vivid demonstrations, that what students will encode is that they did an unusual activity and it was fun but not the actual conceptual content of the demo (see Willingham, 2010). For this reason I regard the preparation reading as crucial and would never attempt to use the above approach to teach synaptic transmission ab initio. It is also critical to keep prompting the students to re-encode what they are doing in terms of the target concepts and understanding through questioning at the time and in the follow-up activity.

Of course, I cannot prove that doing it this way will result in better understanding and learning than the approach it replaces but there is good reason to believe that it might. And it’s a lot more fun.


Pouw, W.T.J.L., van Gog, T. & Paas, F. (2014).  An embedded and embodied cognition review of instructional manipulatives.  Educational Psychology Review, 26, 51-72.

Willingham, D.T. (2010).  Why don’t students like school?  A cognitive scientist answers questions about how the mind works and what it means for the classroom.  San Francisco: Jossey-Bass.

Resources: eyewitness testimony (post-event information)

Here are some resources for teaching the effect of post-event information on eyewitness testimony.  There is an application problem for EWT (with guidance for the analysis on page 2) and a brief slideshow to accompany it.  The essay writing advice is pitched towards Edexcel exams, so YMMV.

Resources: the multi-store model of memory

Here are some resources for teaching the multi-store model of memory. There is an application problem using the multi-store model and a writing task to support well formed evaluation of the multistore model based on the SOLO taxonomy.

Will this video stop your students from typing silly things into Google?

Almost certainly not, but it was fun to make.

Reciprocal teaching for deeper understanding

Most of our students won’t go on to study psychology after their A – Level course but one of the things we can teach them that will help them whatever they do next is to read effectively.  In the past it has surprised me how a student might be able to read a complex text very fluently, yet have very poor comprehension and retention of what they have just read. One way of increasing the effectiveness of students’ reading is to use the reciprocal teaching technique originally developed by Palincsar and Brown (1984).

In the form in which I use it, reciprocal teaching is done as a small group activity (4 per group is ideal).  The group is given a text and decide who will take the ‘teacher’ role first.  The routine is:

  • All group members silently read a section of the text.  While they are reading, the ‘teacher’ must think of a question about that section of the text.
  • Once all have finished reading, the ‘teacher’ asks their question of the group.  The group then discusses and agrees on an answer with the ‘teacher’.
  • When the ‘teacher’ is satisfied with the answer, they summarise that section of the text.  A new ‘teacher’ is chosen and the cycle begins again.

The power of reciprocal teaching comes when you establish as a routine in your classroom, and practice is important.  What is crucial is the quality of the questions the ‘teacher’ asks.  They have to be genuine questions that require deep thinking, rather than ones that can be answered simply by pulling a word or phrase out of the text.  For this reason it is helpful to model the process of thinking up a question and discussing it with the class before handing over to the students.  I also find it useful to circulate and monitor the quality of the questions, intervening where necessary. With regular use, reciprocal teaching becomes just ‘our way of reading’.

Reciprocal teaching has been extensively tested and is associated with substantial learning gains.  Hattie (2008) reports an effect size of 0.74. Much of this research has focused on younger learners, many of these with poor reading relative to age, so it is sometimes overlooked that it also has a positive effect on apparently proficient learners of high school age (Alfassi, 2004).

One problem I have encountered, however, is finding suitable texts for my students to use with the technique. Research papers and more advanced undergraduate textbooks are potentially too difficult for students to access, especially if they are new to psychology.  However, the typical A – Level textbook is laden with intrusive ‘pedagogical features’ that deprive the students of opportunities to ask each other good questions and generally ‘grapple with the text’ in productive ways.  Consequently I have ended up preparing a number of my own.  These are written to be ‘just difficult enough’ but kept short enough for students to process them in a lesson phase lasting 15 – 20 minutes or so.  I’ll be tagging these as ‘reading’ when I post them up.

Alfassi, M. (2004).  Reading to learn: Effects of combined strategy instruction on high school students.  Journal of Educational Research, 97 (4), 171-185.

Hattie, J. (2008).  Visible learning: A synthesis of over 800 meta-analyses relating to achievement.  London: Routledge.

Palincsar, A.S. & Brown, A.L. (1984).  Reciprocal teaching of comprehension-fostering and comprehension-monitoring activities.  Cognition and Instruction, 1 (2), 117-175.

Resources: introductory memory concepts

Here are some resources for teaching introductory memory concepts. There is a memory concepts slideshow, some wordlists for serial position demonstrations, a spreadsheet for graphing the serial position demos and a short reading on Milner et al’s (1968) ‘HM’ case study.

A visible thinking routine (VTR) for comparisons

Two very powerful techniques for provoking learning are getting students to make comparisons and using graphic organisers (see Marzano et al, 2001 pp. 14-20).  The process of making comparisons helps with the acquisition and refinement of concepts because it stimulates students to think and rethink the boundary between this and not-this.  It also requires some fairly deep processing of the sort that seems likely to support long term retention of ideas.  The use of graphic organisers helps to facilitate understanding by making it easier for learners to discern the relationships between ideas.  There is consequently strong justification for using comparison tables a lot, and I do.

A standard comparison table with predefined criteria.

Typically, I use a table organised around criteria given by me.  This works well enough but it’s also somewhat unsatisfying precisely because I give the criteria. Marzano suggests this is preferable where convergent thinking is required because the students are unlikely to come up with suitable criteria on their own.  Point taken, but all the same, what we’re presumably shooting for here is students who are capable of defining their own comparison criteria.

I have been developing a visible thinking routine (see Ritchhart et al, 2011) that shows some promise in this direction.

  1. In groups of three or four, students start by generating as many facts as they can about each of the things they are comparing.  Each fact is written in a separate sticky note.
  2. They are then invited to look for correspondences between the facts about each by lining the sticky note up with each other.  It is best to model this with some sticky notes of your own on the board or under a visualiser, and think aloud whilst doing it e.g. “OK, MRI measures energy from water molecules and PET measures energy from a radiotracer…they sort of go together, so I’m going to line these up together…”
  3. Once students have identified some comparisons they can be encouraged to add more facts to match up with any ‘stray’ sticky notes that don’t currently have a corresponding fact about the comparand.

The students have by this point constructed a skeleton comparison table.  The next step is to encourage and support them in distilling and naming their comparison criteria so they can make their comparisons explicit. Depending on the students they might need more or less scaffolding to do this.

The comparison VTR in progress. Students have started identifying correspondences.

Final steps could be:

  • Recording their table, either drawing it up or photographing it;
  • Working as a whole class to draw up a ‘master’ comparison table based on small-group contributions;
  • Translating their table into well-formed written comparisons (stems can be helpful here).

This process has two significant virtues in that (1) the students do more of the thinking since they go all or at least some of the way to working out their own comparison criteria and (2) it makes their thinking processes visible to you – so you can intervene helpfully – and them, which supports metacognition.

I’ve used this approach several times and am satisfied that it results in comparisons that are as good as those that emerge from a pre-prepared table (although it does take a bit longer).  I am unable to say whether it has any significant impact on my students’ more general capacity to think in comparative ways, although it has intuitive appeal. The important point here is that a visible thinking routine needs to become, well, a routine.  I have not yet used this approach consistently enough across a sufficient range of contexts for my students to incorporate into their everyday thinking repertoire and thereby to permit spontaneous use and generalisation.  My next step, therefore, is to review my schemes of learning for next year and see where the opportunities for this might be.

Marzano, R.J., Pickering, D.J. & Pollock, J.E. (2001).  Classroom instruction that works: Research based strategies for increasing student achievement.  Alexandria, VA: ASCD.

Ritchhart, R., Church, M. & Morrison, K. (2011).  Making thinking visible: How to promote engagement, understanding and independence for all learners.  Hoboken, NJ: Jossey-Bass.

Resources: brain scanning

Here are some resources for teaching brain scanning.  There is a text on CT, PET and fMRI (.pdf), some application problems (.pdf), a comparison table (.rtf) and a short slideshow (.pptx) with key ideas and images.

Using a timeline to teach synoptic thinking in psychology

A timeline of concepts/theories/observations/applications/innovations in psychology.
A timeline of concepts/theories/observations/applications/innovations in psychology.

We recently moved to a linear/terminal assesment curriculum with a heavy synoptic element (Edexcel A – Level; other brands are available).  As we experimented with different ways of teaching the synoptic elements it repeatedly struck me how much the last seventeen years of modularisation have militated against the kinds of ‘joined up’ thinking that is characteristic of good quality learning in Psychology (and, presumably, other subjects/disciplines).

One manifestation of this is that many of our students lack a coherent sense of how the curriculum fits together chronologically.  I initially wanted to address this so our students were prepared for questions about ‘how psychological understanding has developed over time’ (Edexcel 2015 specification) but as soon as the students got stuck in it became clear that the activity that emerged could potentially provoke a much deeper understanding of psychological ideas in context and the relationships between them.

On a long stretch of noticeboard I made six parallel timelines, each labelled with one of the topics/applications on the specification: cognitive psychology; social psychology; bio-psychology; learning theory; clinical psychology and criminological psychology.  The timeline was marked from 1850 to 2025.  Before the lesson I ‘seeded’ the timeline with a few significant events/innovations (e.g. Darwin publishes ‘Origin of Species’; Wundt opens the first psychology laboratory; Ramon y Cajal presents the neural theory etc.)

In the first phase of the lesson I simply invited the students to populate the timeline with as many concepts/theories/studies/applications/observations as they could.  For this, they worked in small groups, one to a topic.  I encouraged them to work from recall as far as possible but to supplement their memory with material from their notes and to look up additional things they decided were important.

In the second phase, once the timeline had a decent amount of material on it, each group was given a ball of wool, a different colour for each topic.  They were then invited to start connecting the concepts/theories/studies/applications/observations to show how earlier ideas influenced later ones.

As the students started linking things together, observations, insights and questioned emerged quite spontaneously.  It was consequently very easy to sustain a productive discussion using a handful of prompt questions like:

  • What do you notice?
  • Can you see any patterns?
  • Why do you think…?

From this discussion the whole group then distilled some important influences on the development of psychological knowledge and understanding (e.g. the use of the scientific method, refinements in methodology, the interplay between ‘pure’ and ‘applied’ areas, new technologies, and social change).  In the following lesson the students developed their writing by selecting a few ‘strands’ from the timeline and using them as the basis for an essay.

I believe that this provided an opportunity for students to integrate the things they already knew into a more coherent and stable conceptual structure.  The students reported that it was engaging and thought provoking.  Time (and the examiner, of course) will be the judge of whether it really did have the intended effect.  But I was sufficiently impressed to regret not having thought of this before.  My intention for the coming academic year is to start the timeline very early on and add to it gradually over the year.  My hope is that I can thereby build that ‘joined up’ thinking right through the course.

psychlotron.org.uk has re-entered the building.

The original psychlotron.org.uk psychology resource website started in 2005 and was regularly updated until 2013.  At that point, fatigue, exam specification changes, cancer (my partner’s) and then open heart surgery (mine) collectively intervened to bring further updates to a halt.

As I now have material I’d like to share and a bit more time and motivation I’ve decided to pick up where I left off in 2013.  If you used the site before you’ll notice I’ve ditched the lovingly hand-crafted html of yore and will now be building psychlotron using WordPress.  I’m hoping that this will make managing the content a bit more straightforward and the addition of things like tags and a search box will make it easier to find what you’re looking for.

If you’re looking for links to resources posted on the old website, try the archive link on the right hand side.  I’ve combined all the old resource links on one big fat web page; you’ll have to scroll down until you find what you’re after.

New resources will be posted in the new ‘blog’ format and tagged to make them searchable.  Here’s an experimental one to see if the process works as intended: an application problem for teaching the multi-store model of memory.