Tuesday, June 21, 2011

Adam McNamara - Can we measure memes?


Part of the standard criticism of memes is that no one has ever seen one, by which neuroscientists mean that there has been no neurocorrelate found in the brain that identifies a meme. This paper looks at the possibility of finding a meme encoded in the brain. Another part of the criticism is that there is no clear definition - McNamara refutes these points and argues that we can define memes and that new technology may allow us to see them in the brain.

Can we measure memes?

  • Department of Psychology, University of Surrey, Surrey, UK

Memes are the fundamental unit of cultural evolution and have been left upon the periphery of cognitive neuroscience due to their inexact definition and the consequent presumption that they are impossible to measure. Here it is argued that although a precise definition of memes is rather difficult it does not preclude highly controlled experiments studying the neural substrates of their initiation and replication. In this paper, memes are termed as either internally or externally represented (i-memes/e-memes) in relation to whether they are represented as a neural substrate within the central nervous system or in some other form within our environment. It is argued that neuroimaging technology is now sufficiently advanced to image the connectivity profiles of i-memes and critically, to measure changes to i-memes over time, i.e., as they evolve. It is argued that it is wrong to simply pass off memes as an alternative term for “stimulus” and “learnt associations” as it does not accurately account for the way in which natural stimuli may dynamically “evolve” as clearly observed in our cultural lives.

Citation: McNamara, A. (2011). Can we measure memes?. Frontiers in Evolutionary Neuroscience. 3:1. doi: 10.3389/fnevo.2011.00001

Here is the beginning of the paper:


Memes, Mirror Neurons, and Modern Neuroimaging

It has been suggested that the sudden explosion of what is considered fundamentally human: consciousness, culture, language, and intellect is a consequence of our evolved capacity to imitate (Donald, 1993). That the driving force for this cultural explosion was the generation of a second environ-mental space in which memes drove biological selection as well as genes (Blackmore, 1999). A meme is a replicator, a cultural unit operating under Darwinian evolutionary principles analogous to a gene, but a distinct replicator in its own right (Dawkins, 1976; Goodenough and Dawkins, 1994). A meme in layman terms is a concept or idea, embodied by a word, a phrase, a riff, image, or gesture. A meme “exists” in the world of ideas and replicates by imitation. Memes are fluffy, non-delineated concepts rendering them somewhat untouchable by cognitive neuroscience albeit that they share considerable functional overlap with a seminal discovery in neuroscience. Over a decade ago mirror neurons, encoding the intention of “others,” were discovered (Gallese et al., 1996; Rizzolatti et al., 1996). It was quickly proposed that these neurons, located in regions highly involved in imitation, were the neural substrates upon which language could have evolved (Rizzolatti and Arbib, 1998). The biological observation of neurons facilitating action recognition and replication fully supported a theory of memetics (Blackmore, 2005) and the field of memetics has grown (Heylighen and Chielens, 2008). However cognitive neuroscience has given the idea a fairly wide birth, probably due to the aforementioned non-measurable, indefinable nature of memes. This paper briefly reviews the biologically based work on the evolution of language. The paper concludes cognitive neuroscience can, and should, apply considerable weight to the investigation of memetics. Firstly, the paper suggests that although memes may not be quantifiable, the traces of the neural processes involved in memetic replication and storage within the central nervous system (CNS) are measurable. Producing artificial memes for study is easily achieved and has already been done within experimental protocols in a number of fields (see Do We Measure Memes Already?). Modern neuroimaging techniques enable us to quantify changes in neural-network-functional-connectivity-profiles as we perceive, learn, memorize, imitate, or perhaps more accurately “replicate” memes.

The Neat View of Genes

According to popular imagination, genes fit nicely into the physical world view that we can imagine even if not see. They are encoded using a four letter alphabet, lie in long lines and one can imagine reading them in a sensible manner. They are easily defined and their function is delineated. Unfortunately for geneticists the truth is not as simple as the popular imagination would have one believe. Defining a gene/cistron is no easy task – let alone identifying a gene’s impact on an organism’s internal functions. Admittedly there are “start” and “end” coding sequences to a gene, but not all the sequence between these markers are read, non-coding intron sequences are scattered across the gene (Gilbert, 1978). Genes can overlap on the chromosome (Normark et al., 1983; Veeramachaneni et al., 2004; Sanna et al., 2008), differing genes can be coded upon the same strand, or not, within the same frame, or not. Overlap can affect regulation of gene expression at the level of transcription, mRNA processing, splicing, or translation (Boi et al., 2004). Introns often also lead to alternative RNA splicing making genes difficult to define by creating alternative pathways for protein expression (Berget et al., 1977; Breathnach et al., 1977). Alternative splicing can account for massive consequences on function (Cavara and Hollmann, 2008) and is crucial to many genes involved in generating immunity (Lynch, 2004). Taking into account the cellular environment, functionality of the “start,” “end,” “enhancing,” and “silencing” sequences is entirely dependent upon other factors. The end product of genes is of course proteins, of which many of these protein’s function is ultimately defined by its molecular environment. The action of a gene becomes far less clearly delineated when one moves away from the common man’s overly deterministic concept of a gene and faces the real complexity that geneticists have to disentangle. It is estimated that we have identified less than 0.3% of all 650,000 estimated protein interactions among the ∼25,000 human proteins (Stumpf et al., 2008). Genes replicate in the physical world and we can measure them. However, we began to measure genes via their phenotypes long before identifying where, and on which chromosome they resided. Genetics was born from the painstaking and careful observation of clear, single gene phenotypes in pea plant petal color (Mendel, 1951). In reality how a gene fits into the organization of an organism is not as clear as one may imagine, how a gene impacts on cellular events and ultimately an organism’s phenotype is only, in very rare cases, fully known. Mendel did not discover the fundamentals of genetics by throwing his hands in the air and exclaiming that it was all too complex and immeasurable. It appears that this is the current scientific stance on memes.

This paper is open access and is available online or as a PDF download.

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