Listening to this on iplayer right now. Science: From Cradle to Grave. About longitudinal studies in medicine and health. It’s presented by the lovely Dr. Ben Goldacre, with his wonderful voice. 🙂
Listening to this on iplayer right now. Science: From Cradle to Grave. About longitudinal studies in medicine and health. It’s presented by the lovely Dr. Ben Goldacre, with his wonderful voice. 🙂
I couldn’t imagine loosing any of my senses, least of all my sight. To go blind slowly over time must be one of the most challenging illnesses a person can have to face. Knowing that there is nothing that can stop a hereditary degeneration of your sight must be heartbreaking, to say the least. Just imagine having the memory of what a flower covered in morning dew looked like as a sunbeam touched the tip of the petal, or being able to recall how you used to look in a mirror but can no longer see yourself, to know that there are wonders beyond most peoples own imaginations that are possible to observe in a sunset and to have all of that knowledge, that discover, taken from you along with your independence has to be one of life’s most unfair consequences of genetic illnesses.
Like any disability that worsens over time you’d hold on to the hope that one day science will find a cure, but it would seem an unfathomable wish for them to cure blindness. This is why the news that came out this week of a microchip that has the potential to restore at least the basic functions of sight seems almost too good to be true.
Some forms of blindness are caused by a degeneration of the photo-receptors within the eye. These are the cells that allow us to interpret light signals into meaning, by building on signals received about colour and brightness. With this information our brain is then able to construct the images that allow us to perceive the world around us. Clever, clever nature.
In people with degenerative eye conditions such as retinitis pigmentosa (RP) the optic nerve is left mostly intact. There are two ‘treatment’ options available at the moment, the first involves forms of gene therapy and other protective factors, which have been shown to slow degeneration in people with this and similar conditions. However, this has to be received at an early enough stage of the degeneration. The second option is what this current research focused on, and sounds more like something from a science fiction film than reality. They invoke electrical stimulation of the surviving retinal networks to try to produce some form of visual experience in people who’s level of degeneration is beyond that which might be helped by the other form of ‘treatment’. More specifically in this case a microchip is implanted under the transparent retina to act as electronic man-made ‘replacement’ photoreceptors.
The chips are able to sense light and create signals from this at many pixel locations. This is achieved using “microphotodiode arrays” or MPDA’s. There are 1500 pixel generating arrays on a chip, and each acts independently as a light sensitive electrode, this is subsequently able to provide an electrical stimulus to the neurons nearby. In this way it is unique to other approaches, within each element is the electrode set allowing for the electrical stimulation of neurons to be caused by the reception of light. There are also photodiodes found within the chip which allow for varied amplifications to be transmitted based on the level of light reception.
With the chip in place within the eye, the photodiodes are able to capture an image each, several times a second, simultaneously.
Illustration from the original paper found here . It gives a better demonstration of the set up of the microchip with the electrodes and MPDAs, and also a nice picture of an eye is always a winner. (I can remember dissecting an eye in alevel bio, it was fascinating)
It’s enough to make your head hurt to think about, I mean really. There are 1500 elements able to transmit signals from the photodiodes, which are able to capture an image in a ridiculously small time frame and transfer this into meaningful information by way of electrical impulses to the bipolar cells that would have originally received information from the rods and cones of the eye. With the amount of current that is sent by each electrode determinable by the brightness recorded by each photodiode. Oh, did I also forget to mention that the chip that all of this occurs on is a mere 4mm square in size!
In this trial study of ‘the chip’ three people with hereditary degenerative blindness were given the implant. They were tested 7 to 9 days after the implant with some psycho-physical tests. If they achieved well on these they went on to be tested for recognition of everyday objects. Due to the electrical nature of the chip it was possible for two test conditions to be employed for all these tests, a chip ‘on’ and chip ‘off’ baseline condition, which allowed for statistically significant results to be acquired.
All three patients were able to detect single electrode single pulse simulations, the perception of this varied slightly between patients but they all reported seeing the stimuli.
They went on to distinguish letters from one another, patient one begin able to tell the difference between U and I, and patient three going further by successfully distinguish four letters presented at random. Patients were also tested on pattern recognition, two of the three were able to correctly distinguish the direction of grid patterns, showing that the chips have high spatial resolution capacities.
Patient two show better recognition in further tests, and interestingly was the only patient of the three to have the chip placed in a slightly different part of the eye. In these cases the patient, identified as Miikka, was able to name objects presented in an unknown dining table situation, including distinguishing between a fork and spoon, as well as an apple and banana. In subsequent optional tests he went on to read his name (a clip that many will have seen on the news) and pointed out the fact that they’d made a spelling mistake!
The fact that they’d only had the chips in place for just over a week and this was having an impact on their perception of light is impressive enough, but for one participant to go on to read their own name is quite incredible for a first trial.
It’s difficult to find fault in this study, you could say it only worked very successful on one subject, but that wouldn’t be fair at all. It seems promising that all of the patients were able to respond to light stimuli in the first instances. There are any number of individual differences that might account for the relative different levels of impact that the chip had on all three participants. One might try to say the media exaggerated the findings in some way but the majority of the reports I saw were very careful to give a full background of the type of blindness that this is appropriate for, as well as the fact that it is very new technology and that it doesn’t ‘restore full sight’.
No questioning then that the results are truly remarkable, and although the success wasn’t replicated in all three subjects, all involved had slight improvements above the level of vision that they had previous to the implant. This research is clearly going to continue to develop into something more and more complex throughout its research future and I hope it can go on to be offered to people with RP more widely in years to come.
It is not often that there is a developement of such magnitude that I’d feel comfortable ending on such a hopeful and positive note but I really do think that this will one day be able to improve the everyday lives of those who have degenerative eye sight. I hope that it’ll go on to allow them to regain the independence that has been taken from them by their conditions and also relieving some of the demands on the carers who have to become their replacement eyes at the moment.
The original paper is:
Subretinal electronic chips allow blind patients to read letters and combine them to words
Eberhart Zrenner, Karl Ulrich Bartz-Schmidt, Heval Benav, Dorothea Besch, Anna Bruckmann, Veit-Peter Gabel, Florian Gekeler, Udo Greppmaier, Alex Harscher, Steffen Kibbel, Johannes Koch, Akos Kusnyerik, Tobias Peters, Katarina Stingl, Helmut Sachs, Alfred Stett, Peter Szurman, Barbara Wilhelm, Robert Wilke.
and a full free PDF can be found here !
The BBC are running a special report in November on Young Carers in the UK and have asked people with experiences with caring to share these with them. I shared mine in three parts, as I wrote too much. It’s a sort of conscious stream of thoughts, feelings and memories so I apologise for the poor style but if you are interested here is what I wrote to them:
My name is Olana Tansley-Hancock, and was a young carer from the age of three. I am now 23, and although no longer living at home having been at University for the past four years I will never stop being a carer for my family.
Unlike most other young carers I knew when I was growing up, I had the unusual circumstance of all three of my family members having disabilities and I was the only ‘normal’ one. My mom has grand mal epilepsy, and a degenerative spinal condition, my big brother is also epileptic and in recent years has unfortunately been diagnosed with biological depression also. My little sister, Roxanne (who is adopted) has cerebral palsy, epilepsy and severe learning difficulties. At the time of her adoption I was only 3, my brothers epilepsy had just been diagnosed and was uncontrolled and my parents were still together. However, my father had begun showing signs of bipolar disorder. When I was five my parents divorced. My mom encouraged me to be involved with Roxanne’s physiotherapy and care as it was really the only time mom got to spend with me.
We moved to a new house when I was 5, and then it was just me, Mom, Dietrich and Roxy. Over the years Dietrich’s epilepsy got more and more under control. Although, I do remember some scary moments when he was having medication changes, like the time he lost his memory and tried to strangle me cause he thought I was a stranger. Or the time he got electrocuted by the electric fence in the nearby fields and he had multiple seizures so severe he had a heart attack. I was walking with him in the field on my own at the time, and had to get him home semiconscious. I was only 9. I remember watching my mom performing CPR, and apologising to the ambulance men for ‘wasting their time’ cause normally when he’d fit, a neighbour would drive Mom and D to the hospital and the ambulance man said ‘if you’d waited for a lift from a neighbour your son would have been dead’.
Mom’s fitting used to scare us all too, but we got used to the routine we had to follow when they did happen. We knew to phone the ambulance, to phone her friend to come over, and to have pain killers and a glass of water ready for when she’d come round. I knew where the medications were in the house, I knew exactly how much medication and what medication everyone of my family took to tell the ambulance men when they arrived. I knew how to put my mom, brother and sister into the recovery position, I knew how to insert rectal diazepam, I knew how to do my laundry, I knew how to cook basic dinners, I knew how to take money out of a cash machine and pay for electricity and gas, I knew how to put the coffee on in the morning for mom, I knew all of these things and more and I was only 7.
I never once envied my other ‘normal friends’ with their ‘normal families’ because to me there was nothing abnormal about my family and I still don’t see them as different.
So we didn’t have yearly family holidays off to faraway places, but instead we went on trips to London to the hospital, or to care centres and we’d always get a Burger King on the way home, and being from the Isle of Wight we didn’t have a Burger King ever! We did go on two family holidays in my childhood, both to the same place in Scotland. I have very fond memories of snow, skiing and squirrels. I believe these holidays were paid for by a charity organisation, as we stayed at a cottage that was specially equipped for the disabled.
My sister had respite care every other weekend, and my Brother got a place at a very good boarding school because he was super smart! So from the age of 11 he only came home for holidays. My sister also a few years later got a place at a specialist school for disabled children on the Mainland and she was there from the age of 11. At that time I was 12, and in a drama school on the Isle of Wight. Just two years later my mom’s back went. She has since had 4 operations on her back and undergone many complications due to these. Whilst it was I suppose ‘easier’ once Roxy and Dietrich went to boarding school, my mom’s disability got progressively worse and worse and I was the only one left at home to look after her. At the age of 11 I was introduced to the Young Carers Project on the Island and they’d take me out on the odd weekend to go horse riding or to the cinema.
When I was 14 I was at a private school on a scholarship on the island, my mom cleaned at the school to pay for some of my tuition that wasn’t covered by the scholarship. She did this until she ended up in hospital because of her back. During my GCSE year my sister underwent an experimental operation to readdress the weight distribution through her feet, this was initially thought to have been unsuccessful and we were told she’d never walk again. She defied the odds however after being in plaster casts for 12 weeks and spending her Easter holiday at St. Mary’s Hospital on the Isle of Wight because we didn’t have the space for her at home in a wheelchair.
I was meant to take all 10 of my GCSEs a year early but due to my caring responsibilities I fell ill in the year before my exams, I missed a crucial 3 weeks of school through exhaustion and it was decided that I should only sit 5 GCSEs early. I still achieved grades A*-B for these exams. I then changed schools for the 7th and last time, and went to the local state school. Here I was able to take two AS levels early along with the rest of my GCSEs. Throughout all three years of being at this school my mom was in and out of hospital. I was running the house and doing to cooking, cleaning and shopping. A charity called ‘Crossroads, now Two Counties’ on the island would pick me up once a week and drive me to Tesco to do the weekly shop. I’d then be the one to do most the cooking, and would fit in my school work around everything else. I finished my high school education with Ten A*-B grade GCSEs, Four A-C grade A levels, and One B grade As Level. I always tell my friends/teachers that being a carer gave me an unfair advantage at school when they all saw it as a disadvantage, but I was so determined to focus on something other than my family that I poured about 70% of my energies into school, the other 30% went into Irish Dancing. I had been dancing since turning 14 and it was the only thing that made me forget absolutely everything about home life. When I was dancing nothing else mattered, nothing else existed, and I was going to be good at it.
I got a place at University and chose to go to Royal Holloway as mom had been getting stronger and I felt being only an hours’ drive from Portsmouth was close enough and yet far enough away for me to feel safe about being away from home but also so that mom could regain her independence. I’d taken so much of it away over the years by doing everything for her that had I been only in Portsmouth or Southampton for Uni I really do believe neither Mom or I would have found out who we were over these past four years, relying on each other as we had done for so long.
Over the Christmas Holiday of my second year of uni my mom fell down the stairs, knocking the bone marrow cage out of place that was surrounding the base of her spine. She developed septicaemia and the infection was so aggressive that she was air lifted to Southampton General Hospital for an emergency operation on New Years Eve. I remember the phone call from the nurse at the hospital, she said ‘your Mom says to tell you to carry on with your new years plans, go out and have fun, and she’ll call you in the morning’. None of us realised how serious her condition was until the weeks that followed. She could have died that night, but thanks to the hard work and amazing dedication of the team at Southampton she was okay. She spent the next month in Southampton and I had to put my studies on hold. By mid January I’d worked out a plan that involved travelling up to uni Monday-Wednesday for essential lectures, coming home via Southampton hospital to be with mom’s dogs Wednesday evening to Sunday, the neighbours looked after the dogs on the days I was away. I didn’t know at the time but this sort of thing is called ‘extenuating circumstances’ in university speak, I didn’t ask for any extra considerations for any of the assignments I handed in during or after this time as in my opinion I wasn’t the one in hospital so why did I need special considerations. I still came away from university with a high 2:1 in Psychology. I have spent this past year studying a MSc in Human Neuroscience and hope to do a PhD in a year or so. My interest in neuroscience comes directly from my family, all of them have disabilities that are a direct result of atypical brain functioning. It always comes back to that; the brain. I want to do more than be a physical help to my family, I want to help on a larger scale now, help fix the original problem so to speak.
The support I have had throughout my life has come from my family, they give and they take like any family. Disability has nothing to do with it. The young carers did help, but dancing helped more, finding something that was just mine was the most important thing for me. Other outside help didn’t really come into it, for example I only found out this year that as a carer you should get a free ticket at the cinema when accompanying you’re disabled sister or mom or brother. How has it taken 23 years for someone to tell me this information? Despite these silly little things, I do not feel like I have had a ‘disadvantaged’ childhood any more than someone who comes from a poorer background would have had. There is nothing ‘unusual’ about my family and I would not change a single thing about them, well maybe one thing, it’d be nice if I hadn’t been born ginger (I hear there’s no cure for that).
Anyway, back to the present day, my brother is back living at home, running his own business with help from mom, who is continuing to get stronger despite having a degenerative illness. My sister is at a development centre learning independent living skills and improving herself all the time. I visit her at least every two weeks and we hang out like any sisters in their 20s would (maybe with a little less alcohol and clubbing but still we have our own fun).
I will always care for my family, you don’t stop being a carer just because you no longer fit under the banner of ‘young carer’. Instead you’re simply a ‘carer’, you’re under the same banner as the husbands and wives who care for their spouses who had age related illness, or the children of elderly parents caring for them, there is no longer a distinction. To be a carer at 20 is a lot tougher in terms of outside awareness than being a carer at 8 or 18. My family are my inspiration, motivation and happiness, and I love them.
Hope that’s given some insight into things, I do get that my situation is a little unique. I can’t say I met many ‘young carers’ at University.
Hope to continue to try to understand the brain and go on to fix a few things!
Last chance to sign science is vital petition: 1.30pm Wed 13 Oct! http://bit.ly/scivit
Go do it right now! Thanks 🙂
Today I attended the Science is Vital rally in London outside the treasury to encourage Osbourne to rethink his proposals to cut the funding budget for science.
A plethora of scientists and others were there to show their support, and the afternoon was filled with speeches by people such as Dr Evan Harris, Simon Singh, Ben Goldacre, Colin Blakemore, Dr Petra Boynton, and a smattering of comedy sci!
All in all it felt like a very unified afternoon, and manged to get me thinking and hopefully will have raised the media awareness which we so need! I don’t want my future to be compromised by a government I didn’t even vote for, but it currently looks like this will happen.
I can’t write too much as I’m using my iPhone and it’s irritating to type on, but the rest of this post will be quotes from the day from signs I spotted to what people said..!
Science beats living in a cave
Putting on a stained lab coat dr evan Harris ‘i wasn’t a very good doctor and I was worse at doing laundry’
‘screening for applications at Eton are such that they elimate taking in those with the gene for shame and regret’- dr michael brooks. ‘we are living in a scientific age and deserve scientifically literate MPs’
Colin Blakemore pointing out that less than half of 1% of the GDP is actually invested in science.
Dr Petra ‘nurture young scientists’
Cutting the budget will compromise the training and saftey of young social
Scientists. Cuts in this country will have an impact on being able to do collaborative research with poorer countries, limiting both of our growths.
Science saves lives!!!
Ben goldacre donned an anorak and shared these gems: Nerd Power! The notion of a Brain Drain- already loosing brightest minds in academia to higher paying city jobs. “you either use it or you lose it”.
Things we can do to help!
1) sign the petiton http://scienceisvital.org.uk/
2) write to your MP
3) get others to sign the petiton!!!
4) come to the lobby on oct 12th
5) go along on the evening October 26th to the royal institute and make your views known!
Science is vital, come on guys you know this. Science is in everything, and affects us all! Get on it. Stop the stupidity and spread awareness.
My mom managed to capture the last 30 seconds of Barley eating. I think it’s interesting how she’s trying to completely clear her bowl (in the side that she is already eating from) so one might suggest she is still feeling hungry when she walks away from the bowl, presumably because she ‘thinks’ it is empty!
The saga continues…
More images of Barley eating, these are from the 6th September, this time she didn’t eat her whole bowl and again ate only from the right hand side.
So the left hemispace neglect symptoms seem to still be present. I’m working on getting a video and mom has said she’ll try to get the vet to maybe get a scan of barley’s brain so will post those if/when they happen.
Have been in touch with a researcher in my dept at Royal Holloway who forwarded the info on to a researcher at UCL’s NIC. He seems very interested in it, and pointed out that Balint induced neglect symptoms in a dog in his early studies on neglect.
Again, anyone with any information that might be useful please get in touch with me. I should get back to writing up my research project, draft is due in next week and I’ve not written a great deal so far.
It’s difficult for me to write with 100% accuracy about her progress as I am at university 80 miles away from home so am relying on interpretations from emails/photographs and updates via the phone from my mom (who is being incredibly helpful, so big thanks is due!).
But Barley’s most recent progress seems quite promising. My mom said she’d noticed Barley’s ‘fussy eating’ (as she calls it) about 2/3 weeks ago after what was likely to have been another stroke since her first major stroke just over a month ago, which left her with a strong left side weakness which she is now recovering from. The photo’s she has sent today indicate that if she is showing signs of neglect or another similar neurological condition that these symptoms are beginning to subside. However, I still think that they way in which she is eating is still very interesting, see the below photos for an illustration.
There seems to be a definite right side preference for the food bowl, (image one) and she clears a whole half almost down a straight line bisection before she moves across to the second ‘half’ of the bowl on her left hand side (image 3). The fourth picture seems to indicate she has changed position slightly, as in the previous photos she is standing right in front of the bowl and in this image she seems to be at it’s side. Again I’ll stress that I do not know precisely how she is eating, I keep trying to get my mom to work out video on her photo so we can have a more accurate step by step portrayal of this.
The fact that she’s managing now to eat her entire bowl without promting is a nice postive sign, I suppose as cool as it is that she’s showing these signs of a neglect I do really want her to get better and make a good recovery. I’m not all about ‘the science’.
I’ll end with this image of Barley being looked after by our new Puppy called Moya (who’s in training to be a dog for the disabled for my mom who has a degenerative spinal condition. I love Moya, she is awesome even if she ate my teddy bear last time I went home!)
Thanks to all of you who’ve seen the post about Barley and have shared it around. If anyone has any suggestions as to how I might better test for neglect signs other than with her food bowl please don’t hesitate to put them forward! I’m also not sure how long neglect can last in a dog when it hasn’t been induced medically for scientific research purposes. So I’d be most grateful for any info from those with veterinary science backgrounds or experience with such things as well. All other information about this condition that anyone may have would be really great to see too!
So I really thought that I’d written a post about Unilateral Neglect before but apparently I’m just imagining that! Perhaps my confusion is because I did write an essay about it for the first course I took last year, and hence forth I’ve become all muddled and confuddled that I can no longer differentiate from the work I ‘have to do’ and the blog posts I enjoy doing…
Anyway, this is the most perfect time for me to write about unilateral (or hemispatial) neglect, as my dog appears to be displaying the symptoms! Brilliant isn’t it? I shouldn’t be this excited but I can’t help it.
She is a 16 year old Whippet x. Lurcher who used to spend her days chasing bunnies and sometimes catching them, but now just potters about the place and would rather just stare at a field of rabbits and keep walking than bother to do anything about them. A few months ago Barley had a stroke, she suffered severe left side weakness and although has gained a lot of mobility back still has a slightly wonkey head. I believe she is still having small strokes and that she must have had one about a fortnight ago that affected her posterior parietal cortex. My reasons for suspecting this are outlined below, after my brief explanation of unilateral neglect symptoms in humans.
Okay, so here goes the ‘science’. Hemispatial neglect can occur following damage to the right or left posterior parietal cortex, most commonly occurring however in the right and usually as a result of a stroke. The form of neglect can be both extrapersonal, representational and/or personal. In right hemispherical damage the effects tend to be longer lasting and more severe, though most patients do recover over time.
In cases of extrapersonal neglect patients fail to be aware of objects on the contralateral side of their lesion, in most cases this means that they neglect objects in the left side of space. For patients to be diagnosed with hemispatial neglect no other explanation such as a motor or sensory deficit can be present (Vallar, 1998). This form of neglect can involve near space (or peripersonal space) or far space, or both. Often patients will recover over time from hemispatial neglect syndrome. It’s common for these patients to fail to draw the left hand side of a picture, as illustrated below, or for them to even eat food only from the right hand side of their plate and not realise that there is still food on the left to be eaten.
In these cases patients neglect the contralesional space in their memories and imagination of places, objects and people. Representational neglect is far more common to right hemispherical damage and is found in conjunction with the extrapersonal visuospatial neglect described above (Bartolomeo, D’Erme, & Gainotti, 1994).
Personal neglect differs in that the patient fails to recognise or use parts of their own body that are on contralateral side of their brain damage. Patients are reported to be unaware of their own limbs, claiming for example that the left leg attached to them belongs to somebody else and is not theirs. This form of neglect is less common than that of extrapersonal neglect, and may involve additional regions of damage. Right personal neglect following a left sided lesion is extremely rare although some cases have been reported (see Peru & Pinna, 1997).
Now of these three forms of neglect I believe it is quite likely that my dog Barley is suffering from extrapersonal neglect following some sort of damage to her Posterior Parietal Cortex in her right hemisphere. The photographs below show my reasons for thinking this is likely. (Thanks go to my Mom for taking these photographs and emailing them to me!)
Number One. Bowl still relatively full of food.
Number Two. Barley eating her food.
Number Three. Barley thinks she has finished eating.
It is pretty clear from these images that she’s really neglecting to ‘see’ the food that is in her left visual field! If mom turns the bowl around so that the food is then on the right hand side of the bowl she continues to eat, albeit a little confused as to where this food has magically appeared from but still.
I hope that these images and experiences of Barleymow have helped illustrate this neurological disorder well, and I will keep tracks on how Barley is doing over time and write about anything new or interesting that happens.
The BBC had this story up recently which I have mixed feelings about. http://www.bbc.co.uk/news/science-environment-11084476
It mentions a survey that highlights the clear lack of public awareness/general knowledge there is regarding important women in science. Would be interesting to see comparative data for general public knowledge of male scientists beyond ‘Einstien’. Or better yet ask people to name a theory or explain why those male scientists are famous.
I think a lot of the ignorance isn’t because these scientists are women necessarily, more likely that our knowledge of science, contemporary or otherwise comes from school and is built upon in further education and through popular culture. As such the theories and people behind them that we hear most about, happen to be those that have been put forward by men. I mean they have had a several 100 years head start on us ladies so it’s not surprising really!
The only way this perception of ‘important women in science’ would be likely to change is if it’s a team of wonder women at CERN who discover the Higgs, or a group of girls who find a cure for cancer, or an individual lady finally finds something concrete and indisputable about cognitive function in the non primate brain!
However, with a still heavily biased population of male scientists I think it is unlikely that these major breakthroughs will be down to one women or a group of only women!
I also don’t think it matters what the sex of an individual is if what they do and discover leads to a change our world or a change in our perception of our world in some way.
Why are we still so hung up on equality between the sexes in areas where it seems illogical and really doesn’t matter in the grand scheme of things?