The other day, I heard the Stranglers' Strange Little Girl for the first time in ages, prompting me to recall having an Indian takeaway in a friend's Morris Oxford somewhere off the Clarendon Road on a sunny evening in 1982. I wonder: does this help explain why older people are more hostile to the Labour party than younger ones?

My response to that particular song was of course idiosyncratic. But it is nevertheless typical. All of us have Proustian madeleines - cues that prompt us to recall some memories. We all, I suspect, have songs which we associate with specific people and places. This is why "trigger warnings" are sometimes necessary: traumatic memories can indeed be triggered. As Daniel Levitin writes:

The brain is not like a warehouse; rather, memories are encoded in groups of neurons that, when set to proper values and configured in a particular way, will cause a memory to be retrieved and replayed in the theatre of our minds. The barrier to being able to recall everything, we might want to is not that it wasn't "stored" in memory, then; rather, the problem is finding the right cue to access the memory (This Is Your Brain on Music, p165)

In a new paper Jessica Wachter shows that this process colours our financial decision-making. Take for example the finding of Erin McGuire and Stefan Nagel and Ulrike Malmendier (pdf), that economic conditions in our formative years influence how much we invest in equities even decades later. From one point of view, this seems absurd: expected returns are the same for all of us. So, how can it happen? Simple. The questions "should I buy shares?" or "What is the economic outlook?" trigger particular memories. For some, these are memories of the bear market of the 70s. For slightly younger people they are memories of the 80s bull market. And these generations invest accordingly.

A similar thing, says Professor Wachter, explains why shares fell so far - in hindsight by too much - when Lehmans collapsed. This triggered memories of (reading about) the Great Depression and hence alarm. (Luckily, though, it also reminded the Fed of the Great Depression, so it knew what not to do).

I suspect a similar process contributes to older people's greater opposition to Labour. Remember that it is not inevitable that young people should be predominantly left-wing: in 1987, for example, more of them supported the Tories than Labour. So why are things different today?

One reason, of course, is that older people own houses and younger ones don't.

But it could be that different memories are involved. If you are in your mid-50s or older, talk of a left-wing Labour party cues memories of the Soviet Union and of the 1970s - and of the more salient aspects of the 70s such as strikes rather than less salient ones such as the fact that most workers got better real-terms pay rises than they've had recently.

Young people, however, have none of these memories. For them, talk of nationalizing the railways trigger not memories of British Rail sandwiches but of pleasant train journeys in Europe.

Of course, the 1970s were the 1970s whether you experienced them or not. But as David Hume said, actual experiences - impressions - are stronger than mere ideas.

In one sense, all of this might be trivially obvious. In another, though, it's not. Even though the truth should in theory be the same for all of us - in the way that future share price moves will be - we perceive it differently. This is not (just) because we are stupid or dishonest. It's because of how memory works.