Butterflies of the soul

Metaphors for the mind and brain

The idea of the brain as a muscle was popularised with the notion of brain training, and accompanying 'brain strain'. The nephew of Alan Turing has embraced the term 'brain training' in a series of puzzle books ironically called the 'Turing tests'.

In 'The Master and his Emissary' (2009) Ian McGilchrist explores the idea of hemispherical lateralisation, popular since the 1960s after texts like Betty Edwards' Drawing on the Right Side of the Brain. He makes the welcome argument that society has become overly focused on the 'emissary' (the left), to the detriment of the 'master' (the right).

Empty headedness is a trait sometimes also described as absent-mindedness, having your head in the clouds, or being a space cadet. In a more concrete sense, cognitive load theory popularised the idea of cognitive overload, describing how working memory is capacity limited and can indeed, in a sense, be fuller or emptier.

Descartes was very taken with the hydraulic fountains in the Royal gardens he visited in Versaille and St Germain. He speculated that the brain worked similarly, by way of hydraulics. In 'Passions of the Soul' (1649), Descartes describes this hydraulic action occurring when 'animal spirits' in the brains ventricles are agitated.

The metaphor of the brain as a computer is dominant today. It is closely linked with computational understandings of cognition. In the 'The Computer and The Brain' (2000), John von Neumann uses this metaphor to explain how the brain appears to use both digital and analogue operations... and also a peculiar statistical language all of its own.

Ramon Cajal described neurons as 'butterflies of the soul', gaining his insights from direct observations which he recorded in beautiful drawings. He was referring specifically to interneurons, a specific variety of neuron which he believed to be important to human consciousness through their connective function.

Like batteries, neurons are able to generate and maintain an electric potential, through the exchange of ions (sodium and potassium). In 'Atoms of Mind' (2011) W.R Klemm invokes the battery metaphor, as he explores how the electric operation of synapses has been invoked in quantum explanations of consciousness.

In 'Man on his Nature' (1940) Nobel Prize winner Charles Sherrington likened the brain's operations to a political system. He refuted William James' (1890) idea of a single central nerve cell to which consciousness was attached, and described the human brain as “a million-fold democracy whose each unit is a cell”. More recently, Ari Berkowitz describes different brain systems as a range of political systems, in 'Governing Behavior: how nerve cell dictatorships and democracies control everything we do' (2016).

In the 1660's, Nicolaus Steno described the brain as a machine, arguing that in order to understand it, like any other machine, we must "dismantle it piece by piece and consider what each do separately and together". More recently, in 1988, Neurobiologist Colin Blakemore published 'the Mind Machine' to accompany a thirteen part BBC series about the mind and brain. In it, he claimed that the human brain would not remain an incomprehensible 'black box' forever, rather it is a hugely complex 'machine' capable of being understood.

Mind-mapping is a common practice now. It implies the mind is a terrain to be mapped, but a terrain of a certain kind, with nodes, hubs and connections. The kind of terrain we map is strongly influenced by ideas of schemata that originate with Piaget. In 'The language and Thought of the Child' (1923) Piaget explains how the schema we hold grow and transform (assimilate and accommodate) as we acquire knowledge and skills. In keeping with the mind-map analogy, William James described neural pathways, havling learned that the flow if information through a neuron is one-directional. Later, in 1948, in a paper titled 'cognitive maps in rats and men', Edward Tolman asserted that, based on his rat maze learning experiments, the brain was not so much like a telephone exchange, but rather like a map control room "indicating routes and paths and environmental relationships."

In 'The Blank Slate', (2003) Stephen Pinker revisits the nature nurture debate, and the idea of the infant mind as a 'tabula rasa' 'blank slate' or 'white paper' (of John Locke) as something shaped by its environment.

Spatial metaphors are often used to describe memory, and are also applied as mnemonic devices to enhance memory, known as the 'method of loci', or sometimes 'the memory palace'. In 'In the Palaces of Memory' (1991) George Johnson explores three quests to understand memory, from a philosopher, a biologist and a physicist.

The phrase 'the ghost in the machine' was originally from Gilbert Ryle's The Concept of Mind 1949). It was intended to point out the absurdity of Cartesian mind-body dualism. Ryle used a number of other metaphors for the mind-body problem: 'the sealed signal box', 'the two parallel theatres' and 'the horse in the locomotive', but it was the ghost in the machine which caught on. Arthur Koestler appropriated Ryle's phrase, in his book of the same title 'The Ghost in the Machine' (1967), although dismissed Ryle as a 'snickering' Oxford don. Later the term was also used with reference to the 'Turing test' (for machine consciousness), and also to ideas about AI, influencing popular sci-fi like the 1995 anime film "Ghost in the Shell".

Ideas of the mind as being like software are closely linked to computational psychology. This is at least in part due to the amount of funding for cognitive research that was intended to understand the computational basis of human learning and inference, in order to inform the development of AI. In "Are you a machine" (2007), Eleizer J. Sternberg popularises some of the discussions around consciousness and the brain. https://www.google.co.uk/books/edition/Are_You_a_Machine/cT4QAQAAIAAJ?hl=en&gbpv=0&bsq=inauthor:%22Eliezer%20J.%20Sternberg%22

After beginning his career as a family therapist, Robert Schwartz applied the principles of family therapy to individuals, doing 'parts work' with their internal sub-personalities. In Internal Family Systems Therapy (1995) he describes the structure and roles of the internal family.

The roaming, or sometimes rutting, elephant of the mind is mentioned in various traditional Buddhist stories. The elephant represents the ego, and is to be tamed by cultivating compassion. A recent translation of Kashmiri stories, dating back to around 400CE, 'Once a Peacock, Once and Actress', includes a story in which a King praises a woman for being able to calm people's passions with her teaching, "like a hook that restrains the rutting elephant of the mind from rampaging through the forest of countless virtues" (p.197) Once a Peacock, Once an ActressWritten in Kashmir around 400 CE, Haribhatta's Jåtakamåla is a remarkable example of classical Sanskrit literature in a mixture of prose and verse. https://www.google.co.uk/books/edition/Once_a_Peacock_Once_an_Actress/V5YtDwAAQBAJ?hl=en&gbpv=0

In his 2009 'Radical Embodied Cognitive Science' Antony Chemero broke away form the dominant idea of mental representations, and from the use of rule-based algorithms to represent mental processes. He instead invokes dynamic equations, which are able to describe (if not predict or explain) mental processes that involve agent-environment dynamics. After all, with no environmental interaction, there is no mental activity. This dynamic approach has influenced fields like robotics, like in the Boston dynamics lab.

In his (1989) paper '"recent issues in the analysis of behaviour", B.F. Skinner explained the behaviourist approach to psychology as leaving "what is inside the black-box to those who have the instruments and methods needed to study it properly."

The idea of an internal observer is most often invoked in explanations of vision. Or rather, in pointing out that descriptions of what we know about vision do not account for our actual experience of it. In 1937, Penfield and Boldrey invoked homunculi to explain the location and relative size of somatic and sensory sites in the cortex. (see Penfield's drawing below)

Henri Bergson, in his 1896 essay Matter and Memory, dismissed the brain as "no more than a kind of central telephonic exchange". At the time, telephone exchanges were quite new, and operated manually with switches and cables. Neurons had been recently described as "an infinite series of switches" by French Physician Matthias Duval in a foreword to one of Cajal's books in 1894.

'Dendrite' comes from the greek 'dendron' (tree). The term was coined in 1889 by Wilhelm His. (Quoted in Stanley Finger, Origins of Neuroscience) More evocatively, Cajal extended the metaphor, to describe the cerebral cortex as: "like a garden, full of an infinite number of trees - pyramidal cells - which, by careful cultivation can produce more branches, push their roots deeper, and produce ever more varied and exquisite flowers and fruits". (quoted in Matthew Cobb, The Idea of the Brain). The tree metaphor now includes the process of 'dendritic arborization' or 'dendritic branching', in which neurons 'branch' to create new synapses.