2. 2
1: Introduction.
Vision is one of our seven senses and is based on the most delicate and complex system in the human
body. It has great intrinsic value as a target area for public popularisation and profiling for a swathe of
economic, social and educational reasons. Vision finds much relevance and application in modern
society, in healthcare, optometry and employability for example. Approximately two million people in the
UK are thought to be living with sight loss, and that number is rising (Access Economics, 2009). The
number of and the rate of administration of NHS funded eye tests is increasing (HSCIC, 2013a), with
gross total expenditure dedicated to visual problems in England rising for six consecutive years between
2007 and 2012 (Department of Health, 2013b). Such prevalence of sight problems can have widespread
causes and effects. The three most common causes of severe visual impairment in children, for example,
encompass disorders of the cerebrum, retina and optic nerve (Rahi and Cable, 2003). The consequences
of such widespread health problems reach into a number of sectors, including financial and educational.
For example, Emerson and Robertson (2007) estimate that adults with learning disabilities are ten times
more likely to be suffering from some form of suboptimal sight problem. The increasing importance of
public awareness is further emphasised when considered alongside the millions of pounds a year that
such conditions cost the UK government (Slade, 2014).
The principles underlying our vision have deep evolutionary roots. The first recorded fossils of eyes date
back approximately 540 million years (Parker, 2009), to a period of evolutionary history referred to as the
Cambrian explosion. Since then a rich variety of light sensitive organs have evolved, including pit eyes,
mirror eyes, compound eyes and our own lens eyes, with complex image forming vision thought to have
evolved in excess of 50 times (Land and Nilsson, 2002). Vision, in the sense of photoreception, is a key
sensory ability across many domains of life, and many of its features have been well preserved by
evolution. At the genetic level, genes such as Pax (paired homeobox) 6 have been shown to contribute to
eye development in multiple vertebrates and invertebrates (Gehring, 2005). This gene and its orthologues
highlight similarities in the development of eyes, both within mammalia, and between mammals and
insects (Gehring and Ikeo, 199). Even better conserved are the opsin proteins and their use of the
chromophore retinal to mediate the electromagnetic spectrum‟s interface with biochemical systems,
allowing phototransduction to take place. Photosensation by any opsin employs this retinal chromophore
(Sichida and Matsuyama, 2009), these include the rhodopsins (G-protein coupled receptors-(GPCRs))
used by animals, rhabdomeric invertebrate opsins, or the ion permeable channelrhodopsins of unicellular
flagellates. This universality of vision and its underlying mechanisms gives it a huge importance many
domains of biological science, which should be emphasised at all educational opportunities.
Its wide variety of stakeholders gives the subject of vision exciting potential for science outreach, simply
from the sheer fascination that the topics‟ component phenomena can elicit. From the perspective of
science professionals, research into eyes and vision can be used to popularise and raise awareness of
3. 3
research and progress in an expansive array of fields. Work on a subset of retinal ganglion cells by
Berson et al (2003), or Lucas et al. (2012), for example, implicates visual science in pioneering advances
in circadian biology. It is high impact factor areas like this that the umbrella heading of vision allows
outreach schemes to harness in pursuit of public awareness, something that is becoming increasingly
important as grant-giving institutions continue to seek an educational return on tax funded science (Rull,
2014). Similarly to this, as “benefit to society” and “personal relevance” emerge as key influences over
sources of funding (Rowe et al., 2010), the ease with which public groups can relate to a need for an
understanding of vision becomes an increasinly persuasive argument for funding. The aforementioned
prevalence of sight problems means they impact a huge number of people both directly and indirectly,
through the clinical and industrial sides of eye care, or as patients. Thus, the relevance and benefit of
research into vision has never been better underlined. Furthermore, as the forefront of popular technology
and media becomes more and more screen based, the diversity of applications of visual science
continues to expand rapidly, giving the field great economic potential.
The visual system can also be an extremely useful teaching tool, but is often not fully exploited in this way
at GCSE or A level. Relevance to „real life‟ and the human body has been highlighted as a particular
source of enjoyment in science learning among young people (NFER, 2011). Much is known about the
human visual system, making it extremely relatable to pupils. What‟s more, the visual system remains a
relatively neglected collection of important and stimulating core concepts, particularly in neuroscience,
including synaptic transmission, action potential propagation, sensory transduction and information
processing. Yet, the curricula of some of the biggest players in public education and examination do not
reflect the potential of this example system to aid both teaching and learning. Edexcel, OCR and AQA
have largely monopolised a great deal of scientific examination in English schools, but omissions in
syllabuses are clear and present, with very little specific focus on vision or the eye. This is a deficit that
science outreach can attempt to reduce.
Here, I describe the development of a new visual display unit (VDU), designed to communicate some of
the fundamental principles of the visual sense, in the environment of a science fair. This resource will
focus on a number of key areas, including the principles of colour vision, the evolutionary conservation of
fundamental physiology and common principles and diversification in the anatomy of eyes. This display
unit attempts to generate impact using a variety of interactive components, including anatomical models,
kaleidoscopic „Fly vision‟ goggles and experimental assays which use live Drosophila melanogaster and
light emitting diodes (LEDs).
The generation of this multifactorial resource has been undertaken with a number of core aims: Firstly, to
produce a family friendly public engagement resource that encourages social learning, as children have
been shown to perform significantly better on exhibit related questions, when interacting with museum
exhibits in a social context (Blud, 1990). Secondly, to cultivate an effective educational experience for
users, that will use a wide range of materials to increase the specific and general knowledge of users,
inspiring and enthusing a diverse audience. And finally, to develop a project resource that can be reused
4. 4
and/or adapted for use in similar or different educational forums, in an attempt to deviate from a trend
highlighted by Sumner and Prokop (2013), in which final year projects only ever attain single usage. The
primary exhibition of this composite resource was to be at The Manchester Museum‟s public „Body
Experience‟ event, held on March 19
th
, 2016.
2: Materials and Methods.
Poster design and generation:
Poster design was completed in a three stage process, utilising multiple computer programmes. It was
predetermined, prior to the initiation of the design process, that the final versions of all posters created
would be produced on the graphic design programme Adobe (2003) Illustrator CS, V6. Initial designs
though, were produced on Microsoft (2010) PowerPoint, greater familiarity with which allowed faster
progression through the design process. Once the design had been decided, it was implemented in
greater detail using Adobe software. Printing of three laminated, A1 sized versions was carried out by the
University of Manchester PhotoGraphics unit.
Assay tube construction:
The Drosophila assay tubes/ mazes were created using an amalgamation of cylindrical plastic vials,
ordinarily used for Drosophila stock maintenance, which are readily available in fly laboratories and
transparent to allow optimum viewing of the insects encapsulated inside. As an added benefit, the
standardised diameter of the tubing (25mm) would make the process of transferring flies between holding
vials and assay apparatus easier, and reduce the chance of losing flies during transfer. Consistency of
dimensions would also make the tubing easy to work with, as creating flush joints with components of
differing diameter would have been problematic. Tubing units made angular at one or both ends were
made so using a fine toothed manual hack saw, and were joined using polyethylene glue and adhesive
tape, in order to increase impact tolerance (clear tape used to maintain good external to internal visibility).
In conjunction with tube assembly, each assay container required the cooperative construction of multiple
electrical circuits. Eight of these were produced in total, each incorporating a single diode, single
manually operated switch, LED appropriate resistor and nine volt battery, using components purchased
from RS Components, which are detailed in the table below:
Component: Quantity: Stock number:
Bivar UV5TZ-400-15 UV LED 4 713-5043
Kingbright L-7113VGCK, Round Series Green LED 2 466-3526
Knighbright L7113ID-LC27SF1.5 Round Series Red LED 2 646-6642
Industrial by Duracell Alkaline 9V battery 8 795-1545
RS pro Strap & lead mount battery strap, 1 press stud
contact.
8 489-021
UV/ Green LED resistor 6 755-1-72
Red LED resistor 2 489-0987
6. 6
completed at the stand, or returned at a later date via email or post. Participation in this form of feedback
was encouraged with a chance to win a guided tour around a selection of the Faculty of Life Science‟s
research facilities, including the Manchester Fly Facility.
However, the return rate for this type of feedback media for events such as this one is typically very low,
especially without forced completion factored into resource design. As such, users were provided with a
second option. This additional method of feedback can colloquially be termed a „post-it‟ board, on which
visitors can anonymously attach sticky notes detailing their thoughts on the exhibit. The speed, ease and
anonymity of this technique were employed to increase the chances of receiving feedback from users
disinclined to fill in feedback forms.
Research strategy:
Selection of an appropriate strategy was an essential step in carrying out research into existing vision and
eye based learning resources online. An important consideration was that this project would largely be
aiming at a relatively young stratum of a lay audience. As such, their primary port of call will not be the
niche, highly advanced scientific publication sites from which much of the related research materials
originally stem. High web visibility sites were prioritised for review, so as to assess the range of materials
with the greatest user exposure.
Several key categories of website were targeted for analysis. Firstly, those aimed at a school age
audience which is researching or studying (for exams or homework, for example). Since this is likely to be
the biggest source of usage for resources of this nature, it was important not to replicate existing school
supplements. However, students are not the only demographic with cause for interest in vision. Patient
groups with sight problems are also important viewers, so websites dedicated to visual healthcare were
also an important target for analysis, to assess the level of detail sought by these users. On the other
hand, since this VDU was to be presented at a museum, it was also important to review information
presented by museum websites, to establish an effective format for engaging audiences with a specific
interest in museums. Finally, as the largest video sharing platform in the world, an overview of the most
viewed YouTube resources was also necessitated. The overall search strategy aimed to locate the most
viewed and most visible resources, utilising broad search terminology including “Human vision”, “Vision/
Eye revision resources”, “How do your eyes work” and “Compare human and fly eyes”.
Risk assessment:
Being a public event, the Body Experience mandated full risk assessments from all presenters. For this,
an existing risk assessment from the Manchester Fly Facility was adapted, in accordance with direction
from health and safety coordination staff within the Faculty if Life Sciences (Ms V. Kelly), and Manchester
Museum staff Experience event (Ms V. Grant). Mandatory precautions included spectrophotometry of UV
LEDs, supervised handling of assay apparatus and appropriate containment of electrical circuits.
Evaluation of compliance with the risk assessment would be based on the adoption of all necessary
predetermined precautions. In addition, the setup of the stall was given visual inspection and verbal
7. 7
confirmation from event staff, prior to public admittance to the Body Experience. All documents available
as supplementary material.
3: Implementation.
3.1: Strategic considerations.
The most important consideration to be made when formulating the strategy for this project was how to
most appropriately target the audience. A brief review of available information on the demographics of
previous years‟ audiences, including a video produced by the Faculty of Life Sciences (Manchester Life
Sciences, 2014) highlighted the need to cater to a family dynamic. Additionally, since this event was to be
held on a Saturday (19/03/2016), the average group size attending the museum could be expected to rise
from 1.9, to 3.8 (Morris Hargreaves McIntyre, 2007). It was therefore important to plan ahead for large
crowds, and attempt to avoid a divided audience, since science fair events can often result in young
children actively interacting, while parents remain distanced. As such, the strategy employed used a
multi-faceted display, which delivered information at several levels of detail. This would allow otherwise
passive parents and adults to simultaneously engage at the same time as younger visitors, to create a
scenario similar to that described by Patel and Prokop (2015). Similarly, strategic adoption of a setup
utilising multiple interactive features was also used to extend the likely period of interaction.
The selection of software for poster design was also a strategic decision. Adobe illustrator software was
chosen to maintain stylistic compatibility with existing visual resources from Manchester fly facility. This
would permit reuse in future outreach schemes, and produce a better integrated display at pilot events.
As such, the intrinsic educational value of the final resource would be raised, by extending its functional
lifespan, as per one of the key aims of the project.
It was also vital to consider the array of potential topics that could be covered by the stall, and the
activities that could be used to enhance their delivery. The list of potential topics included, but was not
limited to: the physiology if the human eye and how it differs from that of the fly, the relationship between
the anatomy of the human eye and the physical properties of light (and so concepts such as
accommodation, refraction, spectral composition), colour vision, disorders of sight, phototransduction and
the evolution of vision (and therefore the design of photoreceptors subsequently produced). The final
selection of topics was based on the strengths and weaknesses of existing web resources, as well as the
degree to which particular areas were represented on the internet.
This range of potential topics informed the list of potential activities that could be used to illustrate them. A
number of optical illusions were considered, to illustrate some of the flaws in human visual processing, for
example the Mach band effect, Müller-Lyer illusion, lilac chaser illusion, beta movement, or aftereffect
illusions. Ishihara colour blindness tests were also considered for the illustration of principles of colour
vision. Several spectral preference and colour perception demonstrations were also designed for use with
live Drosophila (supplementary materials). A Drosophila „laser quest‟ style game was also considered, in
which participants would attempt to generate a jump response in flies using a laser pen. Kaleidoscopic
goggles, with lenses of plastic tessellated hexagons were also obtained to demonstrate the composition
8. 8
of insect vision. Finally, interactive models, of a human eye and an ommatidium were also proposed to
enhance the hands-on experience. The decision to include particular activities was based on their
relevance to chosen topic areas, user friendliness, health and safety considerations, cost, capability for
synthesis, variety, interactivity and novelty value.
3.2: Research into existing resources.
In order to save time for the generation of the VDU, it was essential to search for available ideas and
resources that could be adapted or incorporated. Potentially interesting and relevant resources are listed
here.
A key revision resource pool for school age science pupils is the BBC Bitesize system (BBC, 2016), since
it caters to key stage 3 (KS3) and GCSE level syllabuses in England, Northern Ireland and Wales. These
resources revealed that the coverage of vision-related, or even more general neuroscience-related topics
is poor. The KS3 content completely avoids the use of the visual system as an example in the „Nerves
and Hormones‟ section although it touches on the evolution of sight. Importantly, one of the video
resources available makes clear reference to the universal necessity of rhodopsin to photosensation, and
alludes to the molecular changes that it undergoes (http://www.bbc.co.uk/education/clips/z9sq6sg).
The GSCE menu on this site does dedicate a page of its resources on the nervous system to the eye,
but, the supplementary video links are the same ones as those used for the KS3 material. Thus, this is an
opportunity missed to cultivate a layered knowledge in users, something that science fair VDU resources
could easily improve on. One positive, was the recurrent consistency of the style of anatomical eye
diagram used here when compared to the VDU poster designs, highlighting the value of its clarity. Overall
though, detailed information on the functioning of the eye is thin on the ground and topics such as
refraction or the differences between rod and cone cells are barely mentioned, while visual processing
and phototransduction are left completely untapped..
Another site with a high degree of web visibility is the S-cool revision website (S-cool Youth Marketing
Ltd., 2016) targeted at GSCE and A-level students. These eye based resources focus almost exclusively
on the reflexes of the eye to light, and its ability to accommodate. Whilst the detail on these responses
exceeds that presented by the BBC webpages, it further highlights the need to produce resources of
variety when developing outreach products, so as to provide the greatest chance of securing interest from
members of the public based on the availability of novel concepts and information.
Naturally though, students are not the only stakeholders for online information regarding human vision
and eyesight. Patient groups for example, may provide another target market for science outreach and
public engagement. For example, the website for the Royal National institute of Blind People (RNIB,
2016) lists patient friendly descriptions of a number of visual disorders, including 3 common to the
„Disorders of Vision‟ poster produced for the Body Experience – Glaucoma, Retinitis Pigmentosa and
Cataracts. Critically, these pages are aimed at a lay audience, in a similar way to that in which this VDU
focuses on users of a non-scientific background. Therefore it is important to note, once again, the
compatibility of core illustrations with those of the VDU posters. Common purpose has clearly cultivated a
9. 9
common style, familiarity with which will entice members of the public. This specific style of image can be
kept simple, yet anatomically accurate, and permits any number of reader friendly labelling schemes.
However, the material presented by the RNIB goes into much greater depth and detail than science fair
resources can afford to. This may be due to a more specific interest presumed on users of sites such as
the RNIB, for example, because users may themselves be, or know someone to be affected by one of the
conditions described. Conversely, at science fairs or similar events, visitors simply will not have the same
length of time available to them as when undertaking research online in their own time. As a result, the
resources developed for the Body Experience VDU need to be far more selective in the information
presented. In order to cater to the short timescales over which audiences will be interacting with
materials, details of each visual system disorder presented need to be kept concise and snappy. This will
require a refinement and distillation of content compared with the RNIB site, so as not to clutter posters/
resources. Examples of areas that could be considered too much detail for the VDU resources include the
X-linked inheritance of retinitis pigmentosa, surgical procedures for cataracts, or mechanisms for
increasing ocular hypertension in glaucoma.
Analysis of museum based resources was also important, since the final delivery of this project would be
museum based. The Manchester Museum, unfortunately, does not offer online resources directly
comparable to those described above. However, as a similar institution with one of the highest degrees of
web visibility in the country, the London Science Museum (south Kensington) does dedicate some web-
space to some biological education resources.
The Science Museum‟s range of neuroscience related content is quite diverse relative to previously
described online sources. However, material with raw amazement potential is largely absent.
Photoreception and visual processing merit recognition, but with little more than a paragraph dedicated to
each (Science Museum, 2010). However, the simplistic nature of the explanations available correlates
well with the tone that this project hopes to achieve when engaging users. For example, the fact that
photoreceptor cells possess the ability to create an electrical signal is well articulated, but there is a
notable omission of any accompanying details of the process. As such, the Science Museum resources
can be considered components of an effective, yet incomplete, larger scale delivery of information. The
inception of new, physical museum based resources provides an excellent opportunity to build on this
attractive format, enhancing it with further development. For instance, the Science Museum‟s online
resources for vision are very sparsely illustrated, and do not make overt links to evolution, which is odd,
given the versatility of evolution as a tool for arousing the public.
On reflection, one of the major issues with existing resources seems to be a lack of uniformity in
information presentation. Both web page and video resources currently available exhibit effective and
engaging diagrammatic (RobotSpaceBrain, 2014), interactive (Children‟s University of Manchester, 2012)
or narrative (CrashCourse, 2015) features, but typically lack a broad spectrum of topic materials
presented at a consistent level. Part of the reason for this may be that most online resources with high
web visibility or visitor frequency are formatted to supply follow-up material, designed to help an initial
10. 10
interest proliferate. This is a tactic that new outreach resources may benefit from contrasting, so as not to
waste resources „reinventing the wheel‟. Therefore, a new outreach initiative should aim to integrate with
the user‟s intuitive process at a more introductory level, by providing a more varied array of material, with
a uniform assumption of prior knowledge. In this way, a greater diversity of avenues is presented to
young users, with fewer important areas left ignored (as phototransduction often is). Curiosity aroused,
users are then free to further augment their new knowledge online.
3.3: Description of VDU.
The following items were taken forward from the brainstorming and development stages to form the final
components of the display for the Body Experience event:
Posters:
Three A1 size posters, printed on laminated photographic paper were mounted on poster boards situated
behind the stand (Fig. 1; Supplementary material). Through the use of bright colours, these posters were
made attractive and recognisable from a distance. They were kept as simple as possible so that visitors
could easily engage with and understand the materials, making them more likely to approach and remain
at the stand. Simplicity also necessitated that images were large enough for visitors to see and recognise
them from a distance.
The Blue poster, entitled “What is vision?” illustrates three key principles of vision. Firstly, it depicts a
multi-coloured wave image, which represents the range of visible light within the electromagnetic
spectrum. Secondly, two parallel flow diagrams liken the process of phototransduction in the eye to the
process of solar panels converting sunlight into electricity, in an attempt to help users grasp the concept.
Finally, a large coronal section through the eye details its gross anatomy, including the localisation of rod
and cone photoreceptors to the retina and the path of incident light rays. This poster therefore, combines
the physical properties of light with the related anatomy and physiology of the eye.
The orange poster, entitled “Disorders of vision” utilises the same coronal section through the eye as the
first poster, to illustrate where a variety of different visual disorders manifest themselves. These included
Glaucoma (optic nerve), Extraopia/ Esotropia (extraocular muscles), Retinitis pigmentosa (rod cells),
Figure 1: The vision stand, as
presented at the body experience
fair. Image shows how posters
were arranged behind the
presenters, still allowing reading.
11. 11
colour blindness (cone cells) and cataracts (lens). This poster helps visitors to appreciate the vulnerability
of their eyesight and value their eyes as delicate, precious organs.
The green poster entitled “The evolution of vision” (Fig
3; supplementary material) capitalises on the
prevalence of evolution as a topic in the public eye.
Evidence of this favourable representation can be
found in the national curriculum, which states that
schools “should” teach evolutionary concepts and
principles during Key Stages two, three and four
(Department of education, 2015). This poster
harnesses the increased chance of recognition or
familiarity with the topic amongst the audience to draw
people in. It illustrates the light induced conversion of
trans- to cis- retinal as an evolutionarily conserved
principle of light detection. It then compares and contrasts human and insect vision at various levels of
complexity, including eye anatomy, photoreceptor structure, phototransduction enzymes and higher
processing centres. Additionally, this poster reaches out to the live Drosophila demonstrations and the 3D
models of the camera and compound eyes also on display.
Content related models:
The three dimensional anatomical model of the human eye (28x23x22 cm in its largest dimensions) can
be dismantled to illustrate the “eyeball”, bones of the nose and cheek, extraocular muscles, ciliary bodies,
optic nerve, lens, iris, pupil, retina and vitreous humour. This model provides a kinaesthetic interface
where users can consolidate what they have learned about the anatomy of the eye, but also provides an
eye-catching attraction.
The ommatidium model (20x20x25 cm in its largest dimensions) has a hexagonal wooden face, into
which the eight photoreceptors of Drosophila melanogaster are embedded, each colour coded for clarity
and made from plastic wiring. These taper to a point to represent their exit from the compound eye and
into the optic lobes.
Images of both these models can be found in the supplementary
materials.
Live Drosophila assays:
The spectral preference assay uses wild type flies, kept in a three
armed, radial maze that incorporates permanently illuminated red,
green and blue/UV diodes at the end of each arm respectively (as
shown in Fig 3.). In this assay, the flies accumulate at the UV
light, demonstrating their innate preference for a certain
wavelength of light.
Figure 3: Radial arm spectral
preference assay setup, with red,
green and UV circuits attached and
illuminated.
Figure 3: Final version of third poster, “The
evolution of vision”, as designed on Adobe
Illustrator CS.
12. 12
A second preference assay used a four armed, branched maze three housed the same trifecta of LEDs
as the first. This setup contained sevenless mutant flies, which lack UV photoreceptors (Rabbe, 2000)
and illustrates how UV phototaxis is removed by genetic mutation. Alternatively, though, this assay can
also utilise NorpA mutant flies, which are totally blind (Pearn et al., 1996). However, this will unfortunately
render the flies relatively immobile when on display.
The interactive UV assay uses wild type flies in a single, kinked tube with UV LED circuits at each end.
Repeatedly activating each of these diodes in isolation alternately attracts the flies to the illuminated LED,
thus demonstrating the input that light has on their behaviour.
These interactive displays were very successful in drawing visitors to the stand, who then enjoyed the
hands on experience of manipulating the behaviour of some of the flies. These assays facilitated the
explanation of a range of scientific concepts, including the impact of visual ability on behaviour, and the
principle of this phenomenon being under genetic control, even in organisms as simple as Drosophila.
Additional materials:
In addition, A4 sheets of labelled diagrams and explanations were also included, providing additional,
relevant information on a range of topics. These included anatomy of the eye, optics, the light path
through the human eye, refraction, phototransduction, and photoreceptor structure in mammals and
insects (Supplementary material). An optical illusion was also displayed for visitors to experience, taken
from the text book Neuroscience: Exploring the brain (Bear et al., 2007), it allowed users to visualise the
blind spot in their eyes. These materials were considered too specific to be easily relatable extensions of
poster content, and so were reserved for visitors with greater interest or who has trouble initially
understanding some of the explanations.
3.4: Events.
Pilot events:
The events used to trial a selection of the resource that would be used at the Body Experience were
science fairs held on the 17
th
and 18
th
of March 2016, the two days prior to the main museum event.
These science fairs were hosted in the great hall of the University of Manchester‟s Sackville Street
building, as contributions to both British Science week, and the University‟s Science, Technology,
Engineering and Maths (STEM) public and community engagement programme. These events were ideal
testing grounds for the Body Experience project material thanks to the large and diverse audiences
reached by British Science week events. The previous years‟ festival produced over 5000 engagement
events, contacting an estimated 1.6 million participants (British Science Association, 2015). Over the
course of the two days, the selected resources were displayed to an audience of over 500 KS3 and KS4
pupils, from a range of local schools, for a total of five hours.
Unfortunately, due to the timing of these events and spatial constraints, it was not possible to showcase
the VDU for the Body Experience in its entirety (as previously detailed). However, it was possible to tiral
two of the main features that would be central to the museum event: the posters and the live Drosophila
assays. These components on their own were not enough to host an entire science fair stand, so this
13. 13
opportunity was taken to collaborate with other outreach staff from the Manchester Fly Facility, who were
also exhibiting Drosophila based activities. This provided a cooperative environment to improve synergy,
refine presentation narratives and undertake preliminary evaluation of the resources.
Main event:
The Body Experience is an annual event, held at the Manchester Museum and is free for members of the
public. A five hour science event specialising in human biology, it incorporates a multitude of stands and
exhibits, distributed throughout the museum‟s galleries, each dedicated to a specific part of the human
body (this VDU being the eyes, of course). A total of 16 stands were erected, run by a total of 82 research
personnel and volunteers.
The event was formatted in such a way as to encourage visitors to attend all of the stands on offer. Upon
entry, all visitors were provided with a Body Experience „passport‟ – a small paper booklet containing a
list of the stands present, where they could be found and fun facts about the body part they represented.
Attendees could collect a unique stamp from each stand, a full set of which afforded the bearer a lucky
dip prize. This was important because, as a non-registered event, the number of passports handed out
was the best indicator of the numbers attending the event. A total of 540 of these passports were
distributed, at a rate of one per family/ group, unless a party contained more than one child, in which case
each additional child was also given their own. Assuming a weekend average visiting party size of 3.8
(Morris Hargreaves McIntyre, 2007), estimated attendance at the event was well in excess of 2000
people.
4: Evaluation and results.
Pilot events:
The resources were presented at a British science week event, where the attendance of 517 pupils, plus
accompanying school staff was registered. This allowed the exposure of a selection of materials to a
large audience comprised of secondary school pupils from multiple local schools of differing calibre,
ranging from year eight (12/13 year olds) up to year eleven (15/16 year olds), plus teaching personnel
from the same schools. One drawback to this event was the lack of space available for new VDUs and as
such, the material chosen for display had to be showcased as part of a larger, more general VDU by the
Manchester Fly Facility. Unfortunately, no means of formally collecting feedback were in place at this
event; however it was possible to collect verbal feedback from visitors attending the stall. The integration
of the vision resources was clearly effective and well received as one pupil was quoted saying “One thing
I‟ll remember from the event is talking to the people form the Manchester Fly facility at the science fair.”
Overall, verbal feedback was entirely positive and largely directed towards the live assays, highlighting
their success as a means of engaging a diverse school age audience. Users were encouraged to
physically interact with the live assays in person, to improve their enjoyment and learning experience, and
this highlighted some clear strengths and weaknesses regarding the usability of the resources on display.
Use by visitors revealed that the multi-pronged fly light assays were a little too fragile and cumbersome to
warrant physical manipulation by the audience, and additionally, joints in assay tubing needed to be
14. 14
further reinforced with adhesive tape. On the other hand, the kinked, dual diode assay was compact and
rigid enough for visitors to take into their own hands safely. Furthermore, it became clear over the course
of the event, that placing the tubes against a white background (as opposed to the purple University of
Manchester table cloths) drastically improved the clarity of the demonstrations. In summary, these
resources were very well received at these events and were very effective at delivering the desired
information.
Main event:
A key issue that the body experience presentation revealed was that more than just the two presenters
were needed at the stand. Once both presenters became tied up giving explanations to groups of visitors,
it became very hard to engage additional passers-by or additional people joining the rear of the crowd. As
a result, the numbers of visitors engaged with over the course of the day were lower than could have
been possible.
The reinforced assay setups proved to be very effective, all of which maintained full structural rigidity
throughout the event. Despite this, one of the UV LED circuits did suffer a severed connection after
particularly aggressive shaking by one toddler. This highlights the need for stronger soldering at certain
connections, and that a potential re-design of the housing for electrical circuitry should be considered for
future events.
Two forms of evaluation were tested at this event; a „sticky note‟ feedback board for visitors and a quiz
with a prize draw. The sticky note board received a total of 52 feedback notes over the course of the
event. One strong positive from the sticky note evaluation system was a consensus among users that the
exhibit was well optimised for younger people. Comments made by younger, school age visitors
consistently referred to the resources themselves, whilst feedback from adults often made additional
reference to how much their children or younger family members had enjoyed the stall. A full transcript of
all the comments made via this forum can be found in the supplementary material, and here a selection of
the most representative quotes is given:
Parents/ adults: Young children:
“Great way to teach kids” “Very Cool”
“Very informative, kids loved learning about the
eyes”
“Best. Love it”
“Really interesting, loved seeing the flies and
learning how important they are.”
“Hands on and clear explanation. Thank you.”
“Kids loved it” “I loved learning about how flies see”
Over 1/3 of all comments made direct reference to one or more of the interactive activities, highlighting
these as a key strength, with the live assays being the most popular and memorable. However, the „fly
vision‟ goggles were also highly praised, appearing in almost 20% of comments. None of the written
comments made reference to the posters, which might reflect the somewhat unsettled nature of the
15. 15
narratives used at the stand, which were still relatively immature at the time and really required a longer
development/ trial period for full refinement. Bringing posters directly to the viewers‟ attention, rather than
just serving as background information would increase the educational value of the stand further and
possibly elicit more specific feedback comments from users. Directing questions to the audience about
information depicted on posters would be another way to assess the value of these posters.
Unfortunately, feedback from the quiz/ questionnaire sheets was far less informative. As predicted,
uptake was far lower than for the „post-it‟ board, with only one family electing to fill them in at the stand
and eight more returned online, out of the 200 distributed. Although results from these forms were
therefore clearly unrepresentative, they did give positive feedback- in that 100% of the quizzes returned
yielded a complete set of correct answers, suggesting that the content was of educational value and well
absorbed.
Several strategies could be adopted in an attempt to improve response rates of the quiz questionnaire.
For example, the design was far more rushed than would have been ideal, as a result of organisational
difficulties. More aesthetically pleasing handouts may have been more encouraging of completion, or
perhaps the inclusion of interactive activities might make filling them in more attractive and playful.
Excellent examples of interactive strategies that could be adapted or incorporated have been produced
by the National Eye Institute (2013) (see Link List in supplementary materials). Alternatively, a way of
analysing how much people have learned from the resources could be built into the format of the stand,
for example interactive tests during which visitors are questioned while engaging with presenters or the
resources.
Moreover, the receptivity of participants to the information presented was very encouraging. Positive
verbal and written feedback confirmed that as predicted, the content material was of educational value
and intellectually stimulating, while the activities available made were able to enhance the learning
experience of users and provide and enjoyable learning environment. Thus, this VDU was able to meet
many of its objectives, and provides an excellent starting point from which to further improve its structure
the data it can feed back into science outreach schemes.
5: Discussion.
As explained in the results section; the aim of this project, of developing a VDU about vision and the
eyes, was clearly achieved and presented at two separate science fairs. The evaluation of these events,
usefulness of the resources and potential for improvements and other uses are discussed here.
Educational value of the VDU:
Compared to existing resources (section 3.2 and accompanying supplementary material “Link List”), this
resource provides a more inclusive selection of topics. Existing resources tend to focus on one aspect of
vision, for example: the anatomy of the human eye, evolution of vision or reflexes of the eye (pupillary
light reflex, accommodation etc.). Sources providing coverage of a more expansive range of topics
generally do not achieve the level of detail that this VDU aimed to. Those which did strike an appropriate
level (among them some excellent online videos) were often too limited to be effective as the type of
16. 16
broad spectrum educational resource this VDU was designed to be. For example, healthcare related
websites (such as RNIB) were able to describe a number of disorders in detail, but failed to deliver the
appropriate background information. Contributions specific to topic areas like phototransduction,
photoreceptor structure and colour vision were also very scarce. Inconsistency in the level of detail used
was also a typical problem that this project was able to identify and therefore avoid.
Web research allowed the identification of specific strengths and weaknesses in existing materials, and
the highlighting of important gaps in available information. The design of this VDU attempted to address
some of these weaknesses by integrating a number of strategies and topics, which were presented in a
comparable and consistent level of detail, effectively interlinked, and enhanced by interactive displays.
For example, disorders of the visual system were related to the anatomy and physiology of the eye using
intelligent poster design and a model of the eye; synchronising the explanations from different parts of the
VDU. This VDU also exhibits an excellent level of novelty value when compared highly accessed web
resources. This novelty was epitomised by the evolutionary aspect and the comparison between human
and fly, which produced new and highly educational aspects that are hardly found in online resources.
Accordingly, feedback from visitors was excellent, 100% of the 52 sticky note comments were positive,
generally conveying a message of great enjoyment and interest. 28% of the comments made direct
reference to the Drosophila demonstrations, 19% referred to the „fly vision‟ goggles and a total of 36% of
comments made positive reference to one of the interactive activities, rather than just generally good
comments. The stand was so well received on site, that the feedback was even uploaded to social media
by the Faculty of Life Sciences (Harrop, 2016). As such, based on the feedback from user interaction, it
can be concluded that the presentation of this resource at the Body Experience was an overall success.
Unfortunately, the questionnaire, which was coupled to a prize draw, was relatively ineffective in
comparison with the sticky note board, with a very low return rate both online and on the day.
Potential improvements to the resource:
The presentation of this VDU revealed a number of key lessons, which can be taken forward to increase
the value and effectiveness of future resources.
Most importantly, the stand will need to be given a clearly recognisable and easily identifiable title, for
instance “What is vision?”, or “Understanding our eyes”. This will give the stand a clear and obvious
identity, which will enable members of the public to ascertain from a greater distance that this is an exhibit
they are interested in. Having an open title, such as one the aforementioned, will not only engage users
by indicating that the topic of the stand is exciting, but will also generate an attractive atmosphere to the
stand. Open-endedness of the title will entice visitors who have an answer or statement of sorts that they
can test against initial question, but also clearly provides an environment where individuals with no prior
knowledge can approach the stall if they are simply interested in exploring a new or unfamiliar area of
science. In this way, right from the outset, the VDU is openly catering for visitors with all levels of
experience or education, making it a more attractive proposition. Next, the stand will need a clear line of
narration that provides a concise introduction appropriately following on from the title. This introduction
17. 17
should be short, general and fairly basic, so that visitors can easily understand its content at first
exposure. However, it should also contain intriguing information, ideally that will be novel to the majority
of visitors, so that they become inclined to interact with the rest of the VDU. For example, this introductory
taster might describe the principle of phototransduction, focusing on the wondrous process of translating
electromagnetic light energy into electrical nerve impulses to be interpreted by the brain.
Further content should then be packaged into three modules. The main advantage of a modular system is
that not all visitors have to engage with the stand for extended periods of time. Instead, they can choose
their topic(s) of preference, so those with little interest can move along quickly and free up space for
subsequent visitors, whilst more attentive users can experience all modules. Ideally, each module should
open with a question or narrative that engages the visitor, and encourages them to follow the information
presented. This will facilitate more enriching interactions between stall holders and members of the
public, creating an environment that better caters to the individual user. Below is a proposal for the new
modular structure:
Colour vision:
The title/ opening question for this module should aim to engage visitors by contradicting something they
already think they know about colour. For example, an effective opener might be “What are the primary
colours”. This will provoke lots of visitors into making initial contact, as they will assume they know the
answer. Alternatively, it is an easy question for presenters to pose to passers-by. A lay audience,
particularly children will assume from what they know about art, that the primary colours are always red,
blue and yellow. Thus, many will be surprised and curious to hear that in science, the primary colours are
red, blue and green. This will open a clear sequential narrative for this module. Once red, green and blue
have been described in the introduction, presenters can then tell users that these are in fact the three
colours that humans can directly distinguish, leading on to explanations about trichromacy, and the way in
which other colours are perceived through a combination of red, green and blue cone cell activation. This
will then allow the presenter to describe the types of opsin proteins utilised by cone (and rod) cells, an
important topic for this module to focus on, as opsins were not well represented in the content of the first
VDU setup. The range of sensitivities of human photoreceptors can then be compared to that of
Drosophila. This may be done verbally, or through the use of a new poster illustration (supplementary
material), which depicts the continuous spectrum of colour, and where the sensitivities of human and
insect photoreceptors lie. This module will also be the ideal opportunity to ideally showcase the live
Drosophila based demonstrations, which will show how colour vision can dictate behaviour, but is itself
determined genetically. Ishihara colour blindness test plates may also be a good way to involve people in
this module. This module will therefore focus more heavily on the perception of colour than did the
previous “What is vision” poster. The intended outcome will be that visitors show a new appreciation for
how a seemingly continuous spectrum of colour can be generated via discrete photosensation by cone
cells, the functioning of which is the result of genetics.
Basic principles of sight:
18. 18
This module should have a title question that relates directly to the principle of phototransduction, which
will have been touched upon in the general stand introduction. It should centre on turning light into
electrical impulses, for example “What are you really seeing?” (electrical impulses in the brain), or “What
are you not seeing?” (actual photons). The presentation sequence can then go into more detail about the
nature of phototransduction – how it is achieved and why is it necessary. The train of explanation can
then follow the path of energy into the eye (refraction), conversion into action potentials, through the
retinal layers, through the optic chiasm (most users will be unfamiliar with the nasal and temporal
ipsilateral and contralateral pathways) and finally into the visual cortex. The presenter can then also detail
how retinotopy is preserved during higher processing, either verbally, or through the use of a modified
poster (supplementary materials). This poster will utilise systematic labelling of incident light rays, the
retina and the visual cortex to show how the relative spatial positions of incoming stimuli are coded and
preserved.
Disorders of vision:
This module will be able to utilise the existing poster from the Body Experience, as the system of
assigning one exemplar condition to each of the major anatomical parts of the eye was deemed an
effective one. However, it too will need an eye catching title question. This should relate to eye health, but
also address the user directly, for example “How well can you see?”. Alternatively, this question could
relate to a profession that requires good eyesight, for example “Do you want to be/ Could you be a fighter
pilot!?” Once the user has been addressed directly in this manner, the flow of information can follow an
obvious course. If the user wants to be able to see well/ become a fighter pilot, then they must take care
of their eyes. Why is this important – because the eye is very complex and delicate, with lots of sensitive
parts. Examples of anatomical features of the eye can then be given sequentially, and related to the
disorders presented on the poster. Additional materials on a wider spectrum of conditions will also be
necessary, so more people may be able to relate to them. The disassembling eye model will also remain
a useful tool for helping visitors better visualise the structures highlighted by the descriptions of the
disorders being showcased. The take home message for this module will be to look after your eyes.
Assay setups:
As previously mentioned, the Drosophila assays would be incorporated into the new structure as part of
the colour vision module. However, these too could be further optimised.
The assay apparatus needs more substantial housing to better protect electrical components. Larger,
sturdier custom housing would permit more vigorous handling, allowing members of the public to
manipulate more than just one of the assay setups. Broader, flatter containers, rather than tubular ones,
would exert less pressure on wiring, putting less strain on solder when shaken.
The LED setups used were able to elicit a positive phototaxis to UV light alone, and in the presence of red
and green light, but were unable to elicit a phototactic response to green light in the absence of UV. This
inability to produce the generalised positive phototactic behaviour typical of Drosophila may have been a
property of the green LEDs. Spectrophotometry data (supplementary materials) indicates that these
19. 19
green LEDs have a peak intensity at approximately 515 nm, well within the maximal sensitivity range of
Drosophila rhodopsin Rh6 (Yamaguchi 2010), but a peak irradiance two orders of magnitude lower than
the UV LEDs. As such, the use of brighter green diodes may be able to elicit a positive phototaxis.
Alternatively, (Gao et al, 2008) suggest that manipulating the activity of specific subsets of histamine
gated chloride channel (Ort) expressing neurons can be used to cultivate increased green and attenuated
UV spectral preference behaviours in Drosophila. Thus, future setups could also utilise Ort mutants.
Questionnaire:
The feature of the VDU most in need of improvement is the feedback form. Its main design flaw was
attempting to assess learning and user experience. In future it may be more helpful to separate these two
streams of measurement, or even remove one. It has been suggested that museum visitors do not learn
in a way that can be formally measured (Birney, 1995), but that learning in museums comes from guests
being able to relate the information to personal experiences/ backgrounds (Falk et al, 1986). Therefore,
the degree of learning may be better assessed through observational methods; conversationally exploring
how well visitors can apply the concepts explained. Alternatively; integrated, optional, module specific test
activities, which force completion, could be built into future VDU setups. This would leave the leaflets/
flyers dedicated to further promoting the topic areas and propagating learning outside the museum
environment, as a form of Trojan Horse strategy (Sumner and Prokop, 2013). This may be achieved by
highlighting other interesting resources (such as those produced by the Manchester Fly Facility -
http://www.flyfacility.ls.manchester.ac.uk/forthepublic/)
Potential further applications of this resource:
The resources produced for this project also carry huge potential for diversification. As mentioned in the
introduction, vision as a teaching tool is well suited to a vast range of science topics taught in schools.
These include human health and disease, evolution, biodiversity, sensory systems, stimulus coding and
processing, as well as many basic neuroscience concepts such as action potential propagation or
synaptic transmission. Obviously the national curriculum is not open to perturbation by individual science
outreach projects, but teaching staff could easily use some of the content or activities to supplement and
rejuvenate lesson plans. This can be facilitated through the use of communal platforms, aimed at
teachers and fed by a range of cooperative science outreach schemes. Existing platforms include: the
National STEM Centre‟s resources, the Wellcome Trust‟s education resources, or the Manchester Fly
Facility‟s „dros4schools‟ page. Useful resources for schools may include worksheets related to the project
content, poster diagrams, or downloadable lesson plans that utilise the Drosophila assays, similar to
those found on the droso4schools page (Manchester Fly Facility, 2016).
There could also be applications for some of these resources in healthcare communications. The
disorders of vision poster for example would not be out of place on the wall of an optometrist‟s clinic or
hospital waiting room. The accompanying information could alternatively be refined and condensed into a
leaflet for use in similar settings, for people to take away with them after having a new pair of glasses
fitted, or an eye test. Both patient groups, and families affected by sight problems would benefit from the
20. 20
opportunity view this information in the clinical setting or online. The generation of online resources is an
obvious next step for broadening the impact of this project. These can serve a range of purposes for both
the public, and for other science outreach schemes. Public pages would primarily augment and extend
the learning from science fair or classroom scenarios, but can also serve a more basic function, simply as
a source of information. Furthermore, once descried in detail online, these resources may also assist the
development of other outreach programmes, and thus extending their target audiences.
Alternatively, another simple application for these resources may lie in future student projects. For
example, the assays or model ommatidium may be useful in public engagement projects that focus less
on vision and more Drosophila itself. Projects targeting a different setting or audience, for example in the
classroom environment may benefit from adapting the practical activities, as opposed to re-inventing the
wheel and coming up with a whole new set. Used in different settings, the same materials could be used
to collect educational data on different demographic populations.
6: Conclusion.
Science outreach is of ever growing importance in and around the scientific community, with more and
more time, resources and funding becoming dedicated to its propagation. However, the approach to
developing new initiatives and strategies must be considered well judged, to avoid simply re-inventing the
wheel. Here I have described the development and implementation of a new visual display unit that has
successfully educated a lay audience about the principles of vision and the nature of the eye. This
science outreach resource has been crafted to impart information about the origins and evolution of
vision, the way our the human visual system compares to that of other organisms, common disorders of
the visual system, and how the visual system is capable of interpreting light in the first place.
Through laboratory testing and through field testing at multiple public engagement events, the compilation
of resources described here has been able to contact a wide and diverse audience. Feedback from users
ranging from pre-school age children, right the way up to professional scientists has emphasised the
success of these resources at delivering an educational and enjoyable experience to members of the
public, with particular reference to its interactive components.
However, limitations to the strategy used for the operation and evaluation of these project resources,
namely formal feedback and narration, have restricted their true value somewhat. Despite this though,
this project promises to make an extended contribution to science communication. Thanks to appropriate
preliminary research and novel combinations of resources, this project adopts a level and format
previously identified as sub-optimal in existing resources. By meeting a need in this way, the strategy and
products that have begun to be developed here can continue to contribute to the ever growing momentum
and importance of science outreach progress.
21. 21
Acknowledgements:
1. Bailes, Dr H., Faculty of Life Sciences, University of Manchester, 1.203, Stopford Building, Oxford
Road, M13 9PT.
2. Department of Optometry, Faculty of Life Sciences, University of Manchester. Carys Bannister
Building, Dover Street, Manchester, M13 9PL, UK.
3. Grant, Ms V., Family Programme Coordinator, Manchester Museum, University of Manchester,
Oxford Road, Manchester, M13 9PL.
4. Harrop, Dr C., Public Programmes Manager, Welcome Trust Centre for Cell-Matrix Research,
Faculty of Life Sciences, University of Manchester, Michael Smith Building, Dover Street,
Manchester, M13 9PT.
5. Kelly, Ms V., D.1239, University of Manchester, Michael Smith Building, Dover Street,
Manchester, M13 9PT.
6. Patel, Mr S., Manchester Fly Facility, B.4204, Faculty of Life Sciences, University of Manchester,
Michael Smith building, Dover Street, Manchester, M13 9PT.
7. PhotoGraphics Unit, University of Manchester. 1.828, Stopford Building, Oxford Road,
Manchester, M13 9PT, UK.
8. The Manchester Museum. University of Manchester, Oxford Road, Manchester, M13 9PL.
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