analogy and metaphor running amok

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ARTICLES

Analogy and Metaphor Running Amok:An Examination of the Use of Explanatory Devices in Neuroscience

Kathleen L. Slaney and Michael D. Maraun

Simon Fraser University

Abstract

The use of analogy and metaphor as descriptive andexplanatory devices in neuroscientific research wasexamined. In particular, four analogies/metaphors com-mon to research having to do with the brain and its func-tion were illustrated. It is argued that the use of theseand other similar literary devices in neuroscientificresearch sometimes leads to certain conceptual confu-sions and, thus, fails to aid in clarifying the nature ofthose phenomena they are intended to explain.

Scientific enterprise frequently involves the use of complex, difficultto understand concepts and conceptual relations. Employing technicaland otherwise uncommon terms in published research can both limitthe reader’s ability to comprehend clearly what is being reported, aswell as disrupt the stylistic flow, which may further hinder the reader’sunderstanding of the research findings. It is therefore not uncommonfor researchers to make use of literary devices such as analogy, meta-phor, metonymy, and simile in attempts to enhance both the coherenceand presentation of their ideas. In fact, science has a rich history ofemploying metaphor, analogy, and the like, with the aim of easing theburden of describing or explaining complex phenomena. To name buta few examples, the analogies drawn between flowing water and elec-trical current, between pipes and wires, and between pressure and volt-age within the hydraulic model have been instrumental in describingcertain of the properties of electricity; Bohr’s “planetary” model of thehydrogen atom, although not completely correct, highlighted similari-ties between the gravitational force of the solar system and the attrac-tion between an atom’s positively charged nucleus and negativelycharged electrons; the “twisted ladder” analogy of a DNA strand hasbeen a useful tool for describing the structural relation between thebase unit chemical pair “rungs” and the sugar and phosphate “sides”.


154 Journal of Theoretical and Philosophical Psy. Vol. 25, No. 2, 2005

There is no question that the use of analogy, metaphor, and the like,can be extremely helpful in explaining, exemplifying, and clarifyingideas that are difficult to understand when presented in technical lan-guage. Indeed, many scholars are very clever in their use of suchdevices, often making dry material not only more accessible, but alsomuch more interesting to the reader. However, things can tend to runamok when the analogies and metaphors begin to take on a life of theirown. In such instances, the line between the metaphorical and the lit-eral becomes blurred, and what begins as an explanatory aid oftenbecomes thought of, whether intended or not, as a technical concept.Sometimes the chasm between the analogy and that to which it isapplied becomes so wide that it is difficult to determine what use itcould have been in clarifying the technical concept in the first place.The problem here stems mainly from a misunderstanding of particularconcepts and of when it is appropriate to use one as a “stand in” foranother without serious conceptual distortions and/or confusionsresulting.

Neuroscience is a very broad scientific discipline dealing with theextremely complex structure and function of the nervous system, afield with close connections to other disciplines, most notably biologi-cal psychology and cognitive science, which themselves rely heavily onboth the methodological practices and empirical findings of neuros-cientific research. As we probe the brain and related structures of thenervous system, an enormous and complex lexicon develops, onewhose terms are less and less likely to be accessible to any but thehandful of scientists working within a given area of research. Thepotential for the misuse, or inappropriate use, of analogy and meta-phor increases as the breadth and complexity of terminology specific toa particular research program grows.

The present work will illustrate some common metaphors and analo-gies used in scientific work from disciplines having to do with the studyof the brain and its role in a variety of behaviours. For pragmatic pur-poses these works have been subsumed here under the all-inclusiveheading “neuroscience”. Let it be noted at the forefront that the aimof the paper is by no means to indict the use of metaphorical devices inthe neuroscientific discourse. In fact, employment of such devicesmay, in certain circumstances, not only be legitimate, but also of greataid in clarifying difficult concepts and/or relations among concepts.The intent here, however, is to illustrate cases in which the use of suchexplanatory aids is not only of little help in explaining complex ideas,but may, indeed, result in misleading conceptual confusions and inco-herence which impede rather than promote our understanding of theworkings of the brain and the mind.


Analogy and Metaphor Running Amok 155

COMMON ANALOGIES AND METAPHORS

Analogy is a process of reasoning by parallel cases. Through the useof analogy one can often clarify the meaning of something, or the con-nection between two or more things, via a more obvious, or more eas-ily understood, model that resembles that which is being described interms of its logical structure. A metaphor is a figure of speech in whicha name or descriptive term is used to designate some object that isdifferent from, but analogous to, that to which it is properly applicable.Metonymy is a figure of speech which consists in substituting for thename of a thing the name of an attribute of it or of something closelyrelated to it, and simile is a figurative comparison of one thing toanother. As descriptive aids, both analogy and metaphor are usedextensively in scientific discourse. Research concerned with the func-tion and structure of the nervous system is no exception here. In fact,given the complexity and breadth of the subject matter of neuros-cience, it has become commonplace for researchers to substitute tech-nical language with metaphorical language. However, not all analogiesand metaphors share equal representation in research concerning thebrain and the mind, and many of the same literary devices show uprepeatedly in research of this sort. In the present work, four classes ofanalogies and/or metaphors, which are common to research having todo with the structure and/or function of the brain, are presented.

A Brief Note on the Mind Is Brain “Analogy”

Questions concerning the relationship between the brain and mindhave plagued philosophers, scientists, and lay-people for millennia.The mind is brain “analogy” is actually not an analogy at all, but is,rather, a belief stemming from the general dogma of materialism, aphilosophical doctrine which assumes that only matter exists, and thatall else (mind, spirit, etc.) can be ultimately reduced to matter (Lacy,1976). Although there are numerous versions of the more general doc-trine of materialism, on matters regarding the mind-body “problem”,all materialists generally accept that there exists a physical brain.However, they differ in their explanations of the mind and the natureof its relationship, if any, to the brain. A full explication of the variousfacets of materialism will not be attempted here; the point of raisingthe issue is 1) to highlight that the endeavours of the neuroscientisttend to rely heavily on materialist assumptions about the brain and themind, and that it is commonplace for scientists to attempt to reducemental phenomena to specific structures and/or functions of the brain,and 2) that physiological correlates or preconditions of those mentalphenomena sometimes become conflated with the mental phenomenathemselves. As a result, the issue of mind/brain unity/duality is eithercompletely sidestepped, or is made opaque by the practice of treating



the brain and the mind as one entity, usually without explicitly admit-ting so.

One might need to prod somewhat for specific examples in empiricalneuroscience in which “brain” and “mind” are used interchangeablywith no apparent assumption, on the part of the researcher, of changein meaning. However, there exists a not uncommon practice of treat-ing the brain and the being that is in possession of the brain as inter-changeable; that is, the creature and its brain are often conceived asone and the same entity. The question here is whether or not this ismerely an example of metonymy, or evidence of the existence of amaterialist thrust in neuroscientific research, in which that which isconsidered to be “mind” is reduced to, or explained as a product of,the physical brain.

Quite regardless of one’s philosophical position on the mind-bodyproblem, few, including neuroscientists, would have difficulty withexpressions such as: “I conjured the image up in my mind”; “The viewof the harbour passed before my mind’s eye”; “He’s currently not ofthe mind to think your idea a good one”; “She’s totally out of hermind”. Minds are generally considered by most to be possessed bypeople (and, in some, perhaps misguided, cases, animals), and, so,“thinking”, “imagining”, and other such cognition-related predicatesare done by creatures having brains, and not by the brains themselves.But to be a materialist and to speak of minds without reference tobrains would create dissonance. Hence, a much subtler version of themind-brain interchange occurs, that of the creature-brain interchange.For example, on the effect of “split-brain” preparations on monkey’s,Sperry (1965) notes:

After it had been found that the split-brain monkey isable to learn reverse discriminations concurrently withthe separated hemispheres..., the question arose as towhether the two hemispheres could learn their reversetasks simultaneously. (p. 120; emphasis added)

Although this does not constitute a direct example of mind-brainconflation, it is argued here that it is symptomatic of a material mon-ism according to which queries about the mind can be adequatelyapproached via investigations of the brain. It is further argued thatsuch a perspective lies at the heart of many of the analogies and meta-phors that are employed by neuroscientists in their aim to describe andexplain psychological phenomena.

There Are Maps in/on the Brain

Throughout the history of brain research, in order to characterizewhat goes on in the active brains of living creatures, topological andmap analogies and metaphors have often been given special emphasis,



with the aim of promoting a better understanding of the structural andfunctional properties of the brain. Although the now seemingly far-fetched assumptions of phrenology have long been abandoned, in cur-rent research, whose aim it is to characterize the brain and its functionsin terms of an explicit organizational framework, one frequently comesacross similar geographical metaphors in expressions such as: “neuralmaps” (Whitaker, 1971); “cortical maps” and “naming sites” (Calvin &Ojemann, 1994; emphasis added); “patterns of nerve cells”, “topologi-cal code”, and “coded representations in the brain” (Young, 1987;emphasis added); and “tonotopic” and “retinotopic” organization(Rosenzweig et al., 1996; emphasis added). To impose structuralschema on complex phenomena is not, in itself, necessarily problem-atic and it need not be misleading. Obviously, it would be impossibleto engage in explication of any kind without the aid of such organiza-tional schemes. However, the specific relevance of the map analogy isnot altogether clear. Why is it that this particular analogy has realizedsuch prestige in neuroscientific research? What are the features of amap that deem it a logical, or aesthetic, parallel to particular patternsof neural activity?

A map, in the usual sense of the term, is a representation, or sym-bolic description, of something; it can be scaled, distorted, incomplete,and can even contain errors, in which case those who attempt to use itwould likely deem it a poor, or not very useful, representation. Thisbrings us to another important feature of maps: They are used by peo-ple for one purpose or another, an example being to find one’s way inunfamiliar territory. Then there is the act of “mapping”, in which ele-ments from one domain can be transformed into another (codomain)via some mathematical function. This, it would appear, may indeed bea legitimate aim of the neuroscientist. It is reasonable to say, forexample, that the retina can be mapped onto the visual cortex(Hacker, 1987). But this is merely to say that particular patterns ofstimulation of the rods and cones of the retina are predictive of corre-sponding patterns of the firing of neurons in the visual cortex. It saysnothing of the existence of maps in, or on, the tissue of the brain. Fur-thermore, given that maps are representations of things, even if it werecoherent to assume that the cortex is organized in such a way as to insome sense “map” our perceptions, is this merely to say that activity(i.e., neurons firing) in a particular area of the cerebral cortex is associ-ated with certain perceptual phenomena? This would be a legitimateuse of the map metaphor by neuroscientists—as strictly a descriptiveaid for characterizing the physiological correlates of certain perceptualphenomena. Certainly, map metaphors have been useful in describingthe association of particular sensory or motor functions with specificregions of the cerebral cortex.



However, the neuroscientist does not restrict himself to this ratherlimited use of the map metaphor. It is argued here that, in some cases,the use of the map analogy is indicative of a particular theoretical per-spective on the part of the researcher, namely, the representational the-ory of mind. Proponents of this view adhere to the notion of mind/brain unity, and assume that our perceptions of the external world arein some way represented in our minds (brains), just as maps representthe topological features of geographic regions. The general picturesketched by this philosophical doctrine, the historical roots of whichstem back to the idealist notions of Descartes and Locke, is this: Infor-mation about the external world is taken in by the sense organs, whichthen transmit that information along neural pathways to specific areasof the cerebral cortex, at which point the information is, in some way,“imprinted” on the cortex, thereby constituting an internal representa-tion of that which has been perceived. Then, by some unknown pro-cess, the mind gains access to these internal representations, “telling”the possessor of the mind/brain what has been perceived (cf. Sterelny,1990).

David Marr’s computational theory of vision provides a good exam-ple of such thinking. He states:

if we are capable of knowing what is where in the world,our brains must somehow be capable of representing thisinformation . . . . The study of vision must thereforeinclude . . . an inquiry into the nature of the internal rep-resentations by which we capture this information andmake it available as a basis for decisions about ourthoughts and actions. (1980, p. 3; emphasis added)

And then later:

the senses are for the most part concerned with tellingone what is there. Modern representational theories con-ceive of the mind as having access to systems of internalrepresentations. (1980, p. 5; emphasis added)

J.P. Frisby, an experimental psychologist of vision, and an admirer ofMarr, adds that

there must be symbols inside our heads for the things wesee, symbols which themselves are unlike the things theyrepresent. Upon opening up a patient’s head for a brainoperation, the surgeon does not find there a miniaturestage-set of the world! All he finds is a pink blancmange-like mass of brain cells. So it is an inescapable conclusionthat there must be a symbolic description in the brain ofthe outside world, a description cast in symbols whichstand for the various aspects of the world of which sight



makes us aware. (cited in Hacker, 1991, p. 132; emphasisadded)

Such a position contains a number of confusions. First, the sense inwhich the term “representation” is used is completely unclear. A rep-resentation serves to portray, depict, designate, symbolize, exemplify,or stand for something else. For example, a portrait of Henry V isindeed a representation of the man. However, Henry V can neither bea representation of himself nor of his portrait. In other words, thatbeing represented is logically antecedent to the representation. Hence,to have something be a representation of itself lacks logical coherence,not to mention pragmatic value. For something to be a representation,the concept denoting it must have a rule-governed use; that is, theremust be a correct, and so also incorrect, way of using the concept. Itmust have a grammar, or criteria within which its applications arebounded, and it may only be used by symbol-employing creatures. It isunintelligible to suggest that the brain is capable of representing any-thing at all, let alone sensory stimuli, and that the mind has access tosuch representations. Humans, not brains, can be said to be capable ofrepresenting, and representations are created by language users.

Moreover, in what sense could a representation be “internal”? Onemight possess a representation of something that is unknown to others,or might imagine a representation of something, such as a map. Doesthe map he or she imagines then qualify as an “internal representa-tion”? But imagined representations are not internal to anything byvirtue of its being imagined, and it does not, at any rate, seem likelythat this is what Marr means when he speaks of “internal representa-tion”. Instead, the “‘internality’ of the representations presumably sig-nified that they are ‘in the brain’” (Hacker, 1991, p. 138). Clearly, the“symbols inside our heads” to which Frisby refers are consistent withthe latter notion. However, as previously stated, it makes no sense toconsider neural activity as symbolic of anything, nor to treat the brainas an entity capable of using symbols. And if Frisby is being metaphor-ical, it is not at all apparent what the metaphor is, nor how it facilitatesa better understanding of vision, save making the somewhat trivialpoint that the brain is involved in some way. How it is involved, how-ever, is not made any clearer.

Secondly, from Marr’s words we can assume that it is the brain thatis capable of representing incoming information, and the mind that hasaccess to this “system of representation”. Even if we could say of thebrain that it represents stimulation of the sensory organs in particularways, what then happens to these representations, and what might bethe nature of the mind’s ability to extract them from the brain?Answering these very questions is, according to Marr, the primary taskof the vision theorist. If one is using the term “representation” in itsordinary sense, then obviously such questions lack intelligibility. How-



ever, one might argue that Marr’s use is a technical one, without anyreference to symbols and their uses (Hacker, 1991), in which case theabove criticisms might be misplaced. However, Marr claims that “arepresentation. . .is not a foreign idea at all—we use representations allthe time”, and he finds it fascinating “that one can capture some aspectof reality by making a description of it using a symbol” (1980, p. 21).In the absence of an explicit technical definition of “representation”,one can only assume from his claims that Marr uses the term in itsusual sense, however confusing his employment of it might be.

Finally, although it is comforting to note that Frisby would notexpect to find “a miniature stage-set of the world” inside the skull of apatient undergoing brain surgery, it is anything but an inescapable con-clusion that “there must be a symbolic description in the brain of theoutside world”. Frisby’s statement lacks a coherent logic, i.e., it doesnot follow that because there is not a miniature replica of the world inthe head that there must, instead, exist a symbolic description there. Infact, while the claim that “there is a miniature world inside the skull” isa coherent, if incorrect, empirical proposition, the claim that “thereexists a symbolic description in the brain” has no sense, and so wouldnot be amenable to empirical verification (or falsification). Despite hisintentions, Frisby clarifies nothing with his words, and, once again,brings us no closer to understanding vision.

The Brain Has a Will of Its Own

Wittgenstein said: “Only of a human being and what resembles(behaves like) a human being can one say: it has sensations; it sees; isblind; hears; is deaf; is conscious or unconscious” (cited in Kenny,1984, p. 125). Yet, in neuroscientific research there are literallythousands of examples in which predicates such as “organize”, “sort”,“direct”, “categorize”, “integrate”, and even “intend”, “want”, “need”,“dominate”, and “control” are applied to the brain. Some of these arevoluntary acts that humans engage in; others lack natural expression ortypical gesture (Ter Hark, 1990), but can be used when expressingone’s state of mind, or inferring another’s from their behaviour. It isunlikely that the typical researcher is suggesting that the brain is reallycapable of intentional acts and the like. However, if the purpose ofusing such literary devices is as explanatory aids, then one must inquireas to the nature of these analogies or metaphors, since there is no obvi-ous sense in which attributing psychological predicates to the brainhelps us better understand the mind. In what way could such predi-cates be parallel to or representative of the structural or functionalproperties of the brain? Unfortunately, in such cases the line betweenwhat is meant to be literal and what is meant to be metaphoricalremains completely obscured.



A number of scholars have been pessimistic about any potential util-ity the application of such devices could have for explaining non-human phenomena (cf. Bennett & Hacker, 2003; Hacker, 1987; Kenny,1984; Szasz, 1996). Kenny, considers what is commonly “defended as aharmless pedagogical device” as the “reckless application of human-being predicates to insufficiently human-like objects”, and has namedthis practice the homunculus fallacy, “since its most naı̈ve form is tan-tamount to the postulation of a little man within a man to explainhuman experience and behaviour” (p. 125). Mereology is the logic ofpart/whole relations and Bennett and Hacker (2003) have coined theexpression mereological fallacy to denote the mistake made by neuros-cientists of “ascribing to the constituent parts of an animal attributesthat logically apply only to the whole animal” (p. 73). What follows isMilner and Glickman’s (1965) introduction to Sperry’s aforementionedarticle, “Cerebral Organization and Behaviour”, which constitutes aparadigm example of the homunculus fallacy:

Sperry finds that each hemisphere of the brain is capableof perceiving, learning, and controlling instrumentalresponses independently of the other. In fact, the twohemispheres can be trained, one at a time or even simulta-neously, to solve different discrimination problems. Eachhalf of the brain can control the lower centers and themotor system, but when two conflicting responses arecalled for by the two hemispheres simultaneously, there isno confusion; one or the other hemisphere becomes dom-inant and prevents the output from the other hemispherefrom having any effect at all. Important informationabout the mechanisms of attention can be derived fromexperiments of this sort. (1965, p. 112; emphasis added)

If Milner and Glickman are employing metaphor here, there is noclear evidence of what the metaphor is (for example, use of quotes oritalics to denote special use of a term); nor is it apparent exactly what“important information” about the mechanisms of attention could bederived from the use of such a metaphor, if one is, in fact, being used.Rather than using an inappropriate or ill-fitting metaphor, Milner andGlickman appear to be guilty of misusing language in the manner towhich Kenny refers. Humans are capable of perceiving, learning, con-trolling, solving, dominating, and preventing. And although theremight be a limited sense in which we can apply such predicates tomonkeys, there is no sense in which we can do so to brains.

One might counter by raising the point that others have written inthis way about Sperry’s work, and that, perhaps, Sperry, himself, ismuch more clear in the presentation of his ideas. However, this provesnot to be the case. Although generally the body of Sperry’s articleremains descriptive and technical with regard to terminology, the



introductory and concluding sections are riddled with confusing andmistaken conceptualizations of the brain. For example, Sperry creditsthe brain (or, more specifically, each of the two hemispheres of thebrain) with the ability to learn, communicate, control, and possessmemories. Furthermore, he claims that the corpus callosum has sev-eral different functions, including “the laying down of duplicateengrams in the contralateral hemisphere” and “[keeping] each hemi-sphere up to date on what’s new in the other”, and can be “utilized bythe uneducated hemisphere to tap the engram systems of the trainedside” (1965, p. 119).

Sperry also speaks of the consequences of one hemisphere being“trained to do one thing and the other trained to do the opposite, andthe animal given free choice to perform either or both” and asks thequestion, “With two separate volitional systems inside the same skull,each wanting its own way and each, by training, wanting the oppositionof the other, does each of these thinking entities try to decide foritself?” (1965, p. 122). To suggest that a monkey can be trained makessense, but to claim that one can “train” a brain, let alone one hemi-sphere at a time, does not, unless a wholly different sense of the word“train” is being used, and if that is the case here, its meaning remainsobscure. Although we might infer from its behaviour that a monkey“wants”, “thinks”, or “decides”, to ascribe such attributes to a brainlacks any sense altogether. Sperry refers to the hemispheres of thebrain as “thinking entities”, capable of making decisions for them-selves, and acting in ways consistent with their desires. This is a partic-ularly striking example of the metaphor running amok, leaving behindonly conceptual confusion. Sperry also uses misleading terms such as“volitional systems”. To what does he refer here? Is it some sort ofprocess by which one might exercise one’s will? Of what does such asystem consist? It is not clear. Hence, even if Sperry were using auseful analogy (and he is not), it breaks down with the use of confus-ing, and ill-defined terms.

The Brain Speaks to Itself in Its Own Language

Many areas of neuroscientific study rely on the use of analogy andmetaphor for describing the character of the nervous system, rangingfrom its gross anatomical structure to the electrical excitation of neu-rons and synaptic transmission. With regard to the latter, it is notuncommon to see references to “neuronal communication”, “intercel-lular transfer of information”, “neural code”, or “second messengers”.In many cases, such metaphors are perfectly acceptable, and, if explicit,can be very helpful in simplifying explanations of otherwise very com-plex phenomena. Problems will arise however if the analogies andmetaphors become lost in the process, and we are left with the implica-tion that the central nervous system has its very own “language” with



which different structures within it may communicate. The generalline of thinking in these cases is as follows: Thought involves language;the brain is the “organ of thought”; the brain must, therefore, have, insome sense, a language or grammar, the specific nature of which willeventually be revealed by neuroscientists.

The synapse, the area composed of the presynaptic terminal, thepostsynaptic membrane, and the space between them, may bedescribed in simple terms as the junction at which two neurons meet,and where chemicals, converted from electrical impulses, are releasedfrom one neuron, cross the intercellular space and bind to receptors onthe membrane of other cell, at which point they are converted backinto electrical impulses. This is where the supposed neuronal “commu-nication” takes place. Calvin and Ojemann (1994) claim that “Whatcrosses this border is information, in the form of chemicals” (p. 94;emphasis added). What does it mean to say that “information” crossesthe synapse from one neuron to another? If the sense in which “infor-mation” is being used is the information-theoretic sense (i.e., “bits”),which has nothing to do with representing or semantics, then Calvinand Ojemann’s description could legitimately be considered a technicaldefinition of “synapse”. However, they fail to make this explicit,instead confusing matters further by employing a second analogy inorder to explain the first. What happens at the synapse is, according tothese theorists,

analogous to opening a bottle of perfume at one borderfence and letting the molecules waft across the no man’sland (the synaptic cleft) to the other border fence (thecell membrane). When reaching the other side, the per-fume is “sniffed” by special receptor molecules embeddedin the cell membrane. (1994, p. 94-95)

Obviously perfume molecules cannot be said to “carry information”from one person to another, or anywhere else for that matter. But isthe analogy a good one for describing how “information” crosses bor-ders between neurons? If left strictly as a description of the intercellu-lar transmission of electrical impulses, i.e., the conversion of electricalpotentials to chemicals and then back again, then we would contendthat it is a fair, and even eloquent, use of metaphor. However, it doesnot clarify how “information” crosses the synaptic cleft, and does notgo very far in explaining how the information (in the usual sense of theterm) that we, humans, learn is related to the “information” which istransferred from neuron to neuron.

Some theorists are more daring (and, thus, more confusing) in thelanguage of the brain metaphors they employ. J.Z. Young uses theterm “brain programs” to describe how arrangements of nerve cellsworking together can provide sets of potentialities “that give us all ourpower of sensing, of feeling or acting” (1987, p. 18). He goes on to



state that a brain program is “some sort of list of things to be done inorder to reach an aim” (p. 19). The means by which neurons are ableto “work together” is the brain’s “communication system”, whichYoung has characterized as a coding system, involving “communicationby some sort of language preceded by the language of man” (p. 32),which is specific to the brain, has its own grammar, of which the nerveimpulse is the simplest unit (Young, 1987). It is the job of theneurophysiologist, according to Young, to reveal the nature of the neu-ral impulse “code” and, thus, that of “brain programs”, and the entire“coding system” in which these are embedded.

The confusions apparent in Young’s perspective are myriad. First,Young provides us with the technical notion “brain program”, whichhe defines as “previously organized sets of neurons and their connec-tions, among which selection is made to produce mental and cerebralstates and actions. . .” (1987, p. 19). This immediately conjures up anumber of obvious questions: Who does the organizing, and previousto what? Who does the selecting? What constitutes a cerebral state/action, or a mental one? What Young appears to be suggesting is thatthe “organization” of the brain is innately given, with the neural path-ways associated with all types of human behaviour established prior tobirth. However, “organization”, if Young is employing the term in itsusual sense, is a human activity. Humans impose any such organiza-tion on the brain, most frequently for the purpose of simplifying ourexplanations and descriptions. There can be no organization of thebrain, or anything else, autonomous of human cognition. Young onlyserves to make matters worse by employing the confusing analogy inwhich he suggests that a brain program is “some form of list of thingsto be done in order to reach an aim” (1987, p. 19). It is difficult toimagine what “form” such a list might take. Clearly it is different fromthe conventional employment of the term, such as a list of chores givento a teenage boy by his mother. But how is it different? And, moreimportantly, how is it the same, thereby making it a useful analogy? Itmakes little sense to refer to “lists” within the brain, or to people fol-lowing lists of “things to be done”, when those lists are presumed to besomehow “in their brains”, rather than in their hand, or posted on therefrigerator. Once again, if there is an analogy at play, the advantage itprovides in aiding our understanding of the workings of the brainremains obscure.

A second, and perhaps more serious, confusion results from Young’sconflation of “language” and “code”. The two terms are often usedinterchangeably in research of this sort, and no less so with Young.Although there are logical and semantic connections between the twoconcepts, to consider them synonymous is to misunderstand their dis-tinct meanings. Language, in the ordinary sense, is a rule-governedactivity, a practice, in which rules feature in the teaching and explain-



ing of the meanings of words and sentences, in the justification andexplanation of language usage, in the guiding of behaviour, and in con-stituting criteria for the correct application of concepts (Hacker, 1988).All languages must have a grammar, standards of correctness, or rules,for the correct application of concepts. It is characteristic of rule-gov-erned behaviour, and, thus of language use, that it be regular andintended; hence, acting in accord with a rule alone does not constitute arule-governed activity (Hacker, 1988). One must also intend to engagein such actions. And although language is a form of communication, tocommunicate is not necessarily to use a language.

The use of codes is also a rule-governed activity, in which any type oftext may be enciphered, and the result deciphered by anyone who hasthe key to the cipher. Decoding is the process of returning to the origi-nal text, which is in a given language. According to Harris (1987), thecrucial difference between a language and a code is that the former hasa grammar, while the latter does not. Moreover, the latter presupposesthe former, in that languages can be encoded, as, for example, withMorse code, but the only sense in which a code can be “put into” lan-guage, is when it is being decoded back into the language which wasoriginally encoded.

By these definitions of “language” and “code”, humans are the onlycreatures who can intelligibly be said to use or to have them. Ofcourse, one might employ technical definitions of these terms, but, forthe sake of clarity, must then provide such definitions. Young seems toaim in this general direction when he defines a “code” as “the set ofphysical changes that are used in various combinations to evoke spe-cific responses by a receiving agent that is tuned to receive them”, butmanages to confuse things again when he claims that the “words ofspeech” are an obvious example of such codes. It is unclear how wordscan be considered to be “sets of physical changes”, or how they mightconstitute a code. If the words of a given language are “codes”, then itmust be possible for them to be decoded back into the original textfrom which they were encoded. Where might one begin the process of“decoding” the English language? Such an attempt would doubtlessprove futile as no such original language exists. In Young’s work, “lan-guage” becomes confused with “code”, and “coded messages” in thebrain with “transmissions”. It appears that he will bring neuroscienceno closer to cracking the “neural code” when, as Harris (1987) puts it,there is, in fact, no code to crack. Attempts at gaining an understand-ing of the “language of the brain” will be equally fruitless given thatthere does not exist a coherent conception of such a language.

The Brain Has, Stores, and Contains Information

In their book, Metaphors We Live By (1980), George Lakoff andMark Johnson explore the fundamentally metaphorical nature of our



ordinary conceptual systems. They highlight a number of specific met-aphors that are commonly used in everyday speech, most often withoutour explicit awareness, and which provide clues about how certain fea-tures of our conceptual system factor into how we make sense of theworld and our place in it. One of the metaphors they examine is thecontainer metaphor, which, as its name implies, is suggestive of a ten-dency for people to conceive of physical entities as being enclosed (orcontained) within a larger, non-physical “structure”, and of non-physi-cal entities as being enclosed within a physical structure. It is not unu-sual to hear people make references to things being “in the world”, “inthe street”, or “in the way”. Nor are statements such as: “the mood inthe room”, or “the heightened energy in the stadium” uncommon.Such instances of metaphorical speech are not problematic, and gener-ally create little confusion for those who employ them.

Because the subject matter of neuroscience is, in very large part,concerned with the brain, an organ encased within the skull, and iden-tified in terms of its many subdivisions, references to things “in thebrain” are commonplace. In many such cases, these references are notmetaphorical at all, as they indicate where a given structure is locatedwithin the anatomy of the organism. However, one also frequentlycomes across instances in which the container metaphor is evidently inplay, as any literal reading would be nonsensical. However, it is oftennot altogether clear as to whether the metaphor is intended, and whatpurpose, if any, it is meant to serve. This can easily lead to confusionsand invalid conclusions about the phenomenon of interest. Such casesseem to be particularly prevalent in the general area of cognitiveneuroscience, and particularly in research having to do with memory.

Of course, it is completely reasonable to speak of neurons and gliacells; of frontal, temporal, parietal, and occipital lobes; and of fore-brain, midbrain and hindbrain as being in the brain.1 Conversely, tospeak of memories, thoughts, intentions, desires, and the like as being“in the brain”, goes beyond the bounds of reason, unless such refer-ences are being used in a metaphorical sense, and then only if the met-aphor is useful in describing or explaining that which it stands for.

The domain of memory research is large and, given the highly com-plex and abstract character of the phenomenon under study, vulnera-ble to gross confusions that may result from the use of terms that lackboth clarity and coherence. A few examples should serve to illustratethis point.

1 With the caveat, some will insist, that it is recognized that the par-ticular features of such divisions are arbitrary and dependent on theparticular organizational framework scientists have imposed on thephysical entity we call the brain, which is, itself, the product of an arbi-trary subdivision.



J.Z. Young poses the question “What’s in a brain?” in the introduc-tory section of his book, Philosophy and the Brain (1987). In answer tohis own question he writes:

In order to understand what is meant by the word “brain”as it is used by neuroscientists, we must bear in mind thatthis organ contains in some recorded form the basis ofone’s whole conscious life. It contains the record of allour aims and ambitions and is essential for the experienceof all pleasures and pains, all loves and hates. (p. 8;emphasis added)

Young is correct in stating that the brain is “essential” for all that weexperience. However, as a vital organ, it is not unique in this regard.Without the brain, or the heart, lungs, liver, etc., we would surely die,and experience of any kind would end. But is it really the case thatneuroscientists generally consider the brain to “contain records” ofone’s conscious life, and, if so, of what conceivable form could such“records” take? Autobiographical records may contain a great deal ofinformation about one’s conscious life, but the brain no more containssuch information, much less in any recorded form, than it contains a setof index cards with the chapter headings and contents of one’s plannedautobiography. And to complicate matters further, Young goes on tosuggest that it is the problem of the neurophysiologist to “discover theunits in which the memory record is written in the brain” (p. 18;emphasis added). Obviously such a proposition invites confusion, butno more than the suggestion that any “unit of writing” can be in thebrain, and that the neurophysiologist might be able to discover it.

Other researchers mask their confusions to some extent in whatappear to be weak attempts at technical definitions of memory. Calvinand Ojemann (1994) assert that long-term memory is probably “fixedin some structural change in neurons, such as synapse size” (p. 111).Likewise, Martin (1998) suggests that “. . .meaning or semantic infor-mation about a particular object is represented as a distributed net-work of discrete cortical regions”, within which “features that definean object are stored” in the brain (p. 69). As far as technical defini-tions go, however, these are sufficiently lacking in coherence, or anysemblance of pragmatic value. It is argued here that what is anattempt at a technical treatment of an ordinary concept is, instead, animplicit demonstration of the container metaphor, albeit a misplacedone. Memories are generally conceptualized as lacking in physical sub-stance, and of falling within the domain of the mind, as opposed to assubstantively existing in the brain. Yet, memory researchers seem, forthe most part, to imply that there is physical evidence of memoriesthemselves in the brain, and are, thus, not being metaphorical. It isentirely reasonable to conjecture that there exist particular physiologi-cal preconditions for or correlates of memory. However, although one



can reasonably claim that there are predictable relationships betweenmemory and certain physical changes in neural tissue, memory itselfcan be no more “fixed”, “stored”, or “represented” in either the struc-ture of a neuron or a cortical region, than can feelings of love foranother be fixed, stored, or represented in the chambers of the heart.If we find statements regarding the storing of desires, wishes, inten-tions, and the like, within other physical structures meaningful only ina non-literal sense, then why not so for memories and their relation-ship to the brain?

Young admits that the sense in which one uses such expressions suchas “contain”, “information”, “instructions”, “code”, etc., in referenceto the brain requires “great care”; he claims that it is the “business ofthe physiologist to justify such usages ” (1978, p. 9). However, Youngeither fails to provide technical definitions, or slides readily to and frobetween technical and ordinary usage with neither acknowledgement,nor justification, of which sense of a given term he is employing. It is,therefore, impossible to tease apart these alternative meanings and,instead of gaining further understanding of the brain, its structure andfunction, and its involvement in memory, one is left only with unintel-ligible statements about its “contents”.

CONCLUDING REMARKS: WHAT’S THE DANGER IN A LITTLE

HARMLESS METAPHOR?

To reiterate, analogies and metaphors have an integral function incommon speech and in many areas of scholarly discourse, and havehad a primary role in the growth and development of many scientifictheories. As Hacker (1987) points out, the hydrodynamic analogy wasvery useful to the development of the theory of electricity, in that volt-age can be rightfully considered analogous to pressure, amperage tocurrent, and electrical resistance to hydrodynamic resistance. How-ever, to have failed to recognize that electricity and hydrodynamics arenot the same thing would not only have surely lead to disastrous conse-quences, but would have hindered a proper theoretical understandingof electricity.

Although the present work has focused on the somewhat “darkerside” of scientific custom, there has been no intention to suggest thatall research falling within the domain of neuroscience, and relatedfields, is coloured by the sort of potentially misleading practices thathave been illustrated above. Quite to the contrary, much of theresearch having to do with the structure and function of the nervoussystem either remains technical in its descriptive terms, providing wellarticulated, if complex, definitions for the concepts of interest, oremploys analogies and metaphors which are both explicit and useful.It is quite acceptable to speak of an “orderly mapping of the visualfield” onto the visual cortex (Rozenzweig et.al, 1996, p. 343), as long as



it is recognized that this is a feature of the organizational frameworkadopted by the researcher in his or her attempt to describe predictablepatterns of neural activity in response to perceived stimuli. In addi-tion, if used for strictly descriptive purposes, such as to depict the rela-tionship between particular sensory and/or motor functions withspecific regions of the brain, or to describe the intercellular transmis-sion of electrical potentials, or to illustrate the existence of certainphysiological precursors to or correlates of various cognitive capabili-ties, then the employment of metaphorical devices can be extremelyuseful in disseminating complex ideas.

However, when the answers to both exciting and perplexing ques-tions about the nervous system rest on the use of inappropriate analo-gies and metaphors (i.e., cannot be explained outside of these literarydevices), those answers can lead only to further confusion and misun-derstanding. At the most basic level, the researcher might providevery poor descriptions of the structural and functional workings of thenervous system, in which case the employment of the particular anal-ogy has not only failed to serve its purpose, but may distort importantfindings. For example, confounded in Sperry’s confusing talk of one ofthe brain’s hemispheres exerting its will on the other hemisphere is thevery significant discovery that “severing the corpus callosum depriveshuman beings of the capacity to exercise normally coordinated func-tions . . . And that in turn is to be explained in terms of the disconnec-tion of neural groups that are causally implicated in the exercise ofrelevant capacities” (Bennett & Hacker, 2003, p. 393).

A perhaps even more serious consequence of misguided use of anal-ogy and metaphor occurs when what is being explained or describedbecomes wholly conflated with the metaphor used to explain ordescribe it. Specifically, problems arise when brain and mind are con-flated, when there is talk of internal representations of the outsideworld inside the brain, when predicates usually reserved for humansare attributed to the brain, and when the brain is ascribed with havinglanguage-using abilities. In such cases, the implications go beyond lackof clarity, and strike at the very heart of neuroscientific researchendeavours, in that the empirical testing of theoretical propositionsbecomes completely compromised when the terms or expressions ofsuch hypotheses lack coherence.

For a hypothesis to be testable it must make sense, and in order for ahypothesis to make sense, its constituent terms must make sense andbe used correctly (Bennett & Hacker, 2003). Marr claims that “Thestudy of vision must. . .include. . .an inquiry into the nature of the inter-nal representations by which we capture. . .information” (1980, p. 3),yet such an inquiry is not possible if the meaning of “internal represen-tation” is ineffable. On Sperry’s work in which the two hemispheres ofthe brain were “trained, one at a time or even simultaneously, to solve



different discrimination problems”, Milner and Glickman (1965) con-clude that “Important information about the mechanisms of attentioncan be derived from experiments of this sort” (p. 112); agreed, butalthough that “important information” might support hypotheses per-taining to humans’ capabilities of perceiving, learning, controlling, etc.,it will not give any evidentiary weight to similar claims about the brain,or its hemispheres. According to Young (1987), it is the task of theneurophysiologist to discover the nature of neural code, brain pro-grams, and the entire “coding system” in which they are embedded;however, no such discoveries will be possible as long as the concepts“neural code”, “brain program”, and “coding system” remain eitherconceptually incoherent or (technically) undefined. Frisby (1979) asks“When we see, what are the symbols inside our heads that stand forthings in the outside world?” (p. 8); but any investigation into the exis-tence and nature “symbols” of the external world in our brains (or inour minds for that matter) presupposes that it makes sense to havesymbols in neural tissue, or that, if a metaphor is at play, the relevanthypotheses can be expressed in non-metaphorical language, such thatthey are testable.

And so, despite the potential utility of analogy and metaphor forsimplifying complex ideas, and thus contributing to the developmentand advancement of a theoretical position, it is essential that concep-tual issues are sorted out prior to empirical investigations of the phe-nomena of interest, as the latter are conceivable only to the extent thatthe terms and expressions employed therein are intelligible. Empiricaldiscovery presupposes conceptual clarification, for if the concepts ofinterest to the researcher lack sense, then there can be no empiricalinvestigation of the phenomena which are denoted by those concepts,and a science cannot advance. As Bennett and Hacker (2003) put it sosuccinctly:

Irrespective of the brilliance of the neuroscientists’ exper-iments and the refinement of their techniques, if there isconceptual confusion about their questions or conceptualerror in the descriptions of the results of their investiga-tions, then they will not have understood what they setout to understand. (p. 409)

And, hence, the potential for progress and development of particulartheoretical positions will not be realized.

References

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Author Note

The themes covered in this article were largely inspired by Dr. PeterHacker’s 1987 article “Languages, minds and brains” in Blakemoreand Greenfield’s Mindwaves: Thoughts on intelligence, identity andconsciousness. Correspondence concerning this article should beaddressed to: Kathleen Slaney, Department of Psychology, Simon Fra-ser University, 888 University Drive, Burnaby, B.C., V5A 1S6; e-mail:[email protected].

analogy and metaphor running amok

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