How I Rescued My Brain (20 page)

The damage to my left hippocampus and temporal lobe probably explains my difficulty in recalling the names of things and people, and in remembering what others tell me. The recall of a complete memory is like a successfully baked cake. A cake requires flour, baking powder, eggs, butter, sugar, and flavouring, but if one of these ingredients is missing, the cake will still be cake-like, just not as complete. Similarly, when memory recall is altered by brain damage, there is still a memory, although it will be missing elements of the full memory.

The key thing I take from Doidge's book is that training — repeatedly reactivating a neural network — is necessary for long-lasting brain changes. This results in the brain learning a new skill, or new knowledge, which becomes more embedded with repetition.

Certain brain chemicals cement neuroplastic change by their actions on synapses and neurons. Brain-derived neurotropic factor (BDNF) is a protein that helps to maintain existing neurons and encourages the growth of new neurons and synapses; its supply in the brain is key to neuroplasticity. In the family analogy, BDNF is like the food the family members eat; the amount and quality of this food is critical to their wellbeing. Most neurons have a white sheath — myelin — surrounding the axon, the white matter of the brain. As the neuron becomes more active, the myelin sheath grows in thickness. This increases the speed at which an electrical impulse travels along the axon. BDNF facilitates myelinisation.

Driving a car requires focused attention on sensory, motor, and decision-making aspects. With practice, the neural networks involved in driving are more efficiently connected, thereby requiring less of the driver's conscious attention. Learning to drive well and safely is an activity with a high degree of focused attention and motivation, and both of these factors work to enhance the neuroplastic changes. I remember that as a learner driver, there were an overwhelming number of things to concentrate on. My hands gripped the steering wheel tightly — as if I was afraid that I might somehow let go — and I could only look straight ahead. Conversation about anything other than driving was impossible. But in time, driving became automatic, and I could think and talk about anything, holding the steering wheel lightly, while keeping my eyes on the road.

Neuroplasticity not only means new connections between existing neurons. In a few parts of the brain, new neurons grow from stem cells, in a process called neurogenesis. This is the part that really excites me, because neurogenesis has been found to occur in the hippocampus. Can I restore my damaged left hippocampus and, therefore, get my memory working again?

I best understand the variations of neuroplasticity using a road analogy: new sections of road can be built to provide ways around blockages in the existing road network (synaptogenesis), completely new roads can be built (neurogenesis), and existing roads can be made easier to travel along through widening and resurfacing (myelinisation). The type of change governs the time required: synaptogenesis takes minutes to hours; neurogenesis takes weeks; and myelinisation takes months. Quick neuroplastic changes strengthen existing neural connections, while the slower, but longer-lasting, changes rely on the formation of new connections and new neurons.

My experience of how hard it is to maintain a conversation and how noxious certain sounds have become — some people's voices, music in cafes and shopping malls, and mechanical noises — points me to the belief that I have an auditory-processing problem. Doctor Small has told me that the damage to my brain, while most obvious in the occipital lobe, has also encroached into the temporal lobe on the left side, an area critical for understanding speech. This could explain why I forget what others tell me, and so my difficulty in keeping up in conversation: if I'm slow at taking in what people say, there's less chance of remembering what's been said. The words of new people, with their unfamiliar voices, requires more neural processing than do the familiar voices of family and friends.

I can hear speech all right, and I can make the sounds of the words in speech. But my brain finds it difficult to translate the sounds of speech into engrams — neural representations of words. And there's my difficulty with finding the right word, too. According to Doidge, this problem can be due to ‘fuzzy engrams'.

It reminds me of my trip to Paris in my early twenties, when I relied on my schoolboy French. I could pick up a word or phrase here and there when listening to the native speakers, feeling as if I should be able to understand them, but I couldn't, really.

If my neural circuits for making others' speech intelligible were once dual-lane freeways, they are now single-lane highways; my brain is trying to handle the same amount of auditory traffic as before, but with reduced neural infrastructure. No wonder I'm drawn to quiet places, soft voices, and people who speak at a slower pace.

I begin to wonder: could I retrain my brain specifically to improve auditory processing? I have to find a way of getting my brain muscles working again — my and my family's future depends upon it. Doidge mentions Posit Science, a provider of training programs aimed at reducing cognitive decline in the elderly, and I decide to investigate further.

When I look at the Posit Science website, it says that they offer two programs designed to help the elderly with the common outcomes of cognitive decline associated with ageing. The InSight program improves visual processing. The Brain Fitness program improves auditory processing: forgetting names, slowness of thinking, difficulty in word retrieval, difficulty in deciphering speech, and fatigue in conversation. I'm not elderly, but this describes me perfectly. Could it work for me too?

RECOVERY

12

IT'S SEVEN MONTHS
post-stroke: February 2010. I'm anxious to get on with my recovery, and the more I read, the more it seems like a computer-based cognitive training program is what I need.

I ask Doctor Small about such programs, but he knows nothing about them. Then I ask Doctor Mercer, the ophthalmologist, if computer-based training would improve my visual deficit, but she's not heard of this approach either. She recommends gentle exercise, such as walking along the beach, and tells me that I'll see improvement with the passage of time.

Doctor Small has recommended a neuropsychological assessment, so I decide to put off ordering a program until I speak with the neuropsychologist. A standard assessment includes a clinical interview and a series of tests that aim to measure a person's cognitive functioning, including short- and long-term memory (both verbal and visual), processing speed, spatial skills, conceptual thinking, decision-making ability, and learning capability. I am keen to know the extent of my cognitive capacities, like a high jumper wanting to know how high the bar can be set.

I call the neuropsychologist to let him know that I am a clinical psychologist and I have experience in neuropsychological testing. I'm aware that my prior knowledge of some of the tests might influence the results. He asks me what tests I've used in the past; he'll find alternatives, he says, and thanks me for making contact.

On the day of my appointment, I meet him in his city office, which is quiet and comfortable. The assessment, including the interview, takes almost three hours, with a break in the middle. In one test, he recites a list of eight pairs of unrelated words and asks me to repeat them back to him. After the first trial, I correctly remember two of the eight word pairs. He repeats the list three more times, and after each trial, I repeat back the word pairs I can remember. By the end of the fourth trial, I have only learnt one extra pair — three all up. I'm trying really hard, but the words just don't stick in my mind. This is the type of test I've given many times before, and I know that mine is a poor result: I should've learnt most of the pairs by now.

The neuropsychologist reads out two short stories. Then he asks questions about the content of the stories, and, some time later, asks me to recall as much as I can. Once again, my performance is poor, even though I think I've administered one of the stories myself in testing clients.

My memory for faces and my working memory (working memory typically lasts twenty to thirty seconds) are poor. My visual memory is good, and my vocabulary and speed of processing on visual tracking tests is in the superior range.

My uneven results across the different tests points to an organic cause for my cognitive deficits that's consistent with a brain injury. The neuropsychologist says that the high level of chronic stress and my post-traumatic stress disorder could also have caused the cognitive deterioration. He tells me that he went to a professional-development seminar where the presenter showed the test results of four cases: two with post-traumatic stress and two with brain injury. The participants in the seminar were unable to distinguish the non-brain-injured from the brain-injured by the test results alone.

In his opinion, there's no way I could return to clinical work: my poor memory, difficulties with auditory processing, and mental fatigue would preclude it. Also, my past exposure to trauma puts me at risk of being re-triggered.

I ask the neuropsychologist about computer-based cognitive training. His only knowledge is of the training games available for the Nintendo DS, a small handheld gaming gadget I've seen children using.

On my way home I look at these brain games in a store, and they're simplistic compared with the sophistication of the Posit Science programs. I reach a conclusion: I'm going to have to design my own rehabilitation program. And the first step in that will be brain training.

But what program do I choose?

An internet search reveals there are few commercially available programs, and what little scientific research I can find on computer-based cognitive training points to Posit Science having the most backing for its claims. I locate the Australian distributor, Alzheimer's Australia, and call them. Their adviser, Matthew, tells me that they decided on Posit Science's programs based upon an exhaustive review of existing cognitive-training programs they undertook in 2008.

I will only manage one of Posit Science's two programs with my limited mental energy. I've lost a quarter of my visual field, and the InSight program, which trains visual processing, could help with that. But what hampers me most in daily life? I'm driving okay, and my visual memory is good. All in all, my visual deficit does not restrict me greatly. By comparison, I think of how tiring it is to understand others' speech, and how I need to think out each word before I say it, as though English is now a second language.

Matthew says that studies with older people have shown that those using the Brain Fitness program double their processing speed and gain more than ten years on their scores in standardised measures of memory and attention, leading to improved comprehension. Yes, this is what I need most. According to Matthew, I'm not the usual type of person who enquires about the programs, but he can't think of a reason why I shouldn't give it a go.

I pay for the two-person version of Brain Fitness, thinking that Anna might like to do it too.

BEFORE I CAN
get started on the Brain Fitness program, there is something else I need to deal with. In late March, I walk out of a lift and taste the dry, air-conditioned air. I'm in a shining chamber of marble — almost too shiny to look at.

I haven't been looking forward to today.

Over to my left, a receptionist with perfect hair and a pinched look of concentration sits behind a highly polished counter. She wears a telephone headset: the type that looks like a hairband, where the incoming call goes into only one ear, leaving the other ear free to hear external sounds. It is to this ear that I direct my enquiry. ‘I'm here for a meeting with Mr Tsanov?'

‘He's in conference,' she says. Gesturing behind me with a flick of her head, she adds, ‘Take a seat.'

In the seating area, there is a long coffee table with an etched-glass surface. Set upon this are two tall, fluted vases holding long-stemmed gladioli with pink and red blooms: one at each end of the table. Placed precisely in the centre is a stainless-steel tray, upon which sits a plump glass jug, filled with water to its throat, where blocks of ice congregate. The ice and the beads of condensation suggest that the water is nicely chilled, untouched by anyone this morning. Circling the jug, like a small band of kindergarten children — upright and attentive, as if waiting for their teacher's instructions — are eight clean glasses. I have a dry mouth after the walk from the bus terminal, but I don't want to disturb this perfect arrangement, perhaps put together by the woman with the perfect hair. And I don't want to drink
their
water and feel myself coming under
their
sway. Instead I sit on one of the heavy leather sofas with fleshy armrests, the two facing off like bull-mastiffs.

I reflect on what's happened over the past few months. A property we'd purchased off the plan, which was going to be a retirement apartment for Anna's parents, was due for settlement late last year, but of course we couldn't pay for it. A property investor had recommended Donald Trump's book
Trump Never Give Up
. When Trump faced bankruptcy, he acted on faith that he would work his way through it. He stressed that it was important not to ever give up. I followed Trump's advice to make personal contact with creditors: I phoned the developer and told him, before settlement was due, of our financial position. He sounded accommodating, saying, ‘Get your lawyer to write to us and state your case.' I wasn't keen on this approach: lawyers meant that negotiations would become adversarial and expensive. But we couldn't dictate the process, so what else could we do? Doom and Gloom wrote to the developer with supporting financial and medical documentation, and all we got for our trouble was a legal letter of demand from the developer's lawyers — settle the purchase or we'd be up for damages. I tried making contact with the developer again, but never got a return call.