Confirmation bias

I’m prone to confirmation bias. This is a disadvantage in research, because once I latch onto a hypothesis, I tend to become closed to exploring other possibilities until someone who knows more argues me out of it. But it has an advantage too, because in pursuit of confirmation, I develop sufficient interest in a subject to learn about it in some depth.

Concept-based learning

Tonight I realised that my study method is suboptimal. I probably understand only one-third of what I am reading, which is not good. We employ concept-based learning in our Project Management Concepts course, and that demands that people define and explain the terms they encounter along the way; but I haven’t been doing that consistently in my own study of molecular and cell biology.

In our course, participants create a List of Terms to record terms along with their definitions, also using them in sample sentences. They must also be able to explain these terms as though to a thirteen-year-old child. A few weeks ago, before I installed CM Tooltips Glossary for the Marius Cloete Moulds Web site, I checked out some of implementations of the paid version of this WordPress plugin. One of them was a glossary at a genetics site, which I thought did this simple-explanations thing pretty well. So I’m giving myself homework: I am going to make a glossary as part of my studies.

Background to my homework assignment

I have a friend who has symptoms which I decided are indicative of a CACNA1A mutation. I’ve been stuck in confirmation bias about this for more than a year, and I look forward to hearing the result of her genetic tests to find out whether I was right. In the process of learning about CACNA1A, I am learning about the other CACNA-whatever mutations too. Since calcium channel diseases are rife among autistic people (and relevant to sensory overstimulation, which I am studying), and since I engage with a lot of autistics in discussions about health, it’s hardly surprising that I also recently encountered someone with a confirmed CACNA1S mutation (along with other genetic issues). I introduced her to some of my fellow students, including my possibly-CACNA1A friend.

Now, back to my homework.

My homework assignment

I am going to start my glossary by making an effort to understand every term in this passage:

Spinocerebellar ataxia type 6 (SCA6) is an autosomal-dominant neurodegenerative disorder that is caused by a CAG trinucleotide repeat expansion in the CACNA1A gene. As one of the few bicistronic genes discovered in the human genome, CACNA1A encodes not only the α1A subunit of the P/Q type voltage-gated Ca2+ channel CaV2.1 but also the α1ACT protein, a 75 kDa transcription factor sharing the sequence of the cytoplasmic C-terminal tail of the α1A subunit. Isoforms of both proteins contain the polyglutamine (polyQ) domain that is expanded in SCA6 patients. Although certain SCA6 phenotypes appear to be specific for Purkinje neurons, other pathogenic effects of the SCA6 polyQ mutation can affect a broad spectrum of central nervous system (CNS) neuronal subtypes.

Before I start my glossary, I’m going to define the key terms to the best of my ability, so that I can assess my progress later once I have looked up these terms and studied them properly. Even if I don’t have a clue what a particular word means now, I will still create a wild-guess definition for it. Later, once I have entered the term into my personal glossary, tooltips will appear upon mouseover, and you will be able to learn what they really mean.

Here’s the list of key terms:

  • spinocerebellar ataxia
  • autosomal-dominant
  • neurodegenerative
  • CAG trinucleotide
  • repeat expansion
  • CACNA1A gene
  • bicistronic genes
  • human genome
  • α1A subunit
  • P/Q type voltage-gated Ca2+ channel CaV2.1
  • α1ACT protein
  • 75 kDa transcription factor
  • cytoplasmic C-terminal tail of the α1A subunit
  • isoforms of both proteins
  • polyglutamine (polyQ) domain
  • phenotypes
  • Purkinje neurons
  • pathogenic effects
  • mutation
  • central nervous system (CNS)
  • neuronal subtypes

Do you want to study along with me? If so, copy and paste the quote and the list, and tweet me a link to your own top-of-your-head best-guess definitions. I’ll create a separate post for my wacky first try. Later, we can send each other links to our new improved definitions.


Now read…


My wacky best-guess CACNA1A definitions