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Why do we shake our heads? On the origin of the headshake


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This article discusses several arguments in favor of the hypothesis that the headshake as a gesture for negation has its origins in early childhood experiences. It elaborates on Charles Darwin's observation that children inevitably shake their heads in order to stop food intake when sated, thereby establishing a connection between rejection and the head gesture. It is argued that later in life the semantics of the headshake extend from rejection to negation-just as it can be observed in the development of spoken language negation. While Darwin's hypothesis can hardly be tested directly, this paper takes a novel perspective and looks at the predictions it makes taking a plethora of sources of evidence into account. The question of how head gestures are used in cultures where the headshake is not a sign for negation or where other negative head gestures are in use will also be discussed.
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Why do we shake our heads? On the origin of the headshake
Fabian Bross
Author accepted manuscript. To appear in Gesture.This article is under copyright.
Please contact the publisher for permission to re-use or reprint the material in any form.
This article discusses several arguments in favor of the hypothesis that the headshake
as a gesture for negation has its origins in early childhood experiences. It elaborates on
Charles Darwin’s observation that children inevitably shake their heads in order to stop
food intake when sated, thereby establishing a connection between rejection and the
head gesture. It is argued that later in life the semantics of the headshake extend from
rejection to negationjust as it can be observed in the development of spoken language
negation. While Darwin’s hypothesis can hardly be tested directly, this paper takes a
novel perspective and looks at the predictions it makes taking a plethora of sources of
evidence into account. The question of how head gestures are used in cultures where
the headshake is not a sign for negation or where other negative head gestures are in
use will also be discussed.
Keywords: headshake; backward head toss; negation; refusal; speech
accompanying gesture; embodiment
1 Introduction
In a now famous argumentation, British naturalist Charles Darwin (1872, p. 237)
speculated that the origin of the headshake used for negation in most cultures can be
traced back to an early childhood experience: he observed that when sated, the infant
being breastfed inevitably shakes its head to stop drinking. The aim of the present paper
is to elaborate on Darwin’s observation. While there is much literature surrounding this
topic ranging from psychoanalytical studies (e.g., Spitz, 1957), semiotic analyses (e.g.,
Jakobson, 1972), video-corpus analyses (e.g., Kendon, 2002), studies on the
geographical distribution on gestures (e.g., Morris et al., 1979) to studies
investigating the development of gestures for affirmation and negation in infancy (e.g.,
Kettner & Carpendale, 2013), this paper goes in another direction. Tackling Darwin’s
hypothesis directly is anything but easy; the goal of this paper is to look at the
predictions it makes. By reviewing the available evidence in favor or against these
predictions, I conclude that most of the predictions turn out to be on the right track
although for some of the predictions the evidence is stronger while it is weaker for
The predictions Darwin’s hypothesis makes are that: (i) the headshake should be the
most common gesture to express refusal (or, more broadly: negation) in most cultures of
the world; (ii) the headshake as a gesture should be acquired very early in life; (iii) that it
should also be used by individuals who are not to able learn this gesture by observation,
i.e. those born deaf-and-blind; and (vi) that the headshake should be used by other
mammals breastfed in a similar way. It will be shown that all four predictions turn out to
be mostly accurate, although only with a pinch of salt. While there has been some
previous research concentrating on some of these predictions (especially predictions i
and ii), this contribution tries to take a more broad approach by looking at a whole set of
predictions Darwin’s hypothesis makes (including ones that were not explicitly linked to
the origin of the headshake, i.e., predictions iii and vi). Additionally, new sources of data
will be used when looking at the distribution of head movements in different regions of
the world. For example, by looking at data from sign languages, as non-manual signs
like headshakes are usually borrowed from the surrounding hearing culture in these
visual languages.
I will also make some remarks on other negative head movements used in some
cultures and revisit those movements when discussing Darwin’s hypothesis. It will be,
inter alia, argued that head-movement systems that have so far been described as
expressing negation gesturally by a head toss (e.g., in Turkey, Greece, or parts of Italy),
in fact do not lack headshakes, but do exhibit different head movements including one to
express anaphoric negation (head toss) plus a truth-conditional gestural negator
(headshake). It is argued that a lateral movement of the head is one of the simplest
and often the only possiblereaction of an infant to stop food intake. In repeating this
process time and again, a connection is established between refusal and the head
gesture. Later in life, the gesture is expanded through reduplication to a repeated side-
to-side movement. In addition, the semantics of the headshake extends from mere
rejection to a broader concept of negation, thereby mirroring the development of
negation in spoken language acquisition.
The organization of the paper is as follows. First, Darwin’s hypothesis and its
predictions will be discussed (Section 2). Each of the four predictions and the available
evidence that could possibly speak against or in favor of it will be discussed in a section
of its own. In Section 3 the spread of the negative headshake in different cultures is
discussed, Section 4 investigates the prediction that the headshake as a gesture for
negation is acquired very early, Section 5 is devoted to the question of whether
individuals born deaf-and-blind use the headshake, and Section 6 discusses
headshakes in non-human mammals. Finally, Section 7 concludes.
2 Darwin’s hypothesis and its predictions
Most speculations of the origin of the negative headshake assume that it stems from
some form of avoidance behavior, for example avoiding eye contact (e.g., Jakobson,
1970; Vavra 1976) or refusing food (e.g., Kulovesi, 1939; Sugar, 1941; Spitz 1957). In
this line of argument, the headshake is some kind of ritualized form of looking away or
refusing offered food. The oldest proponent of the idea that the headshake has its
origins in refusing food is Darwin (1872, p. 273), who speculated over the suspected
universality of the signs used by us in affirmation and negation”:
With infants, the first act of denial consists in refusing food;
and I repeatedly noticed with my own infants, that they did so
by withdrawing their heads laterally from the breast, or from
anything offered them in a spoon. In accepting food and
taking it into their mouths, they incline their heads forwards.
[…] It deserves notice that in accepting or taking food, there
is only a single movement forward, and a single nod implies
affirmation. On the other hand, in refusing food, especially if it
be pressed on them, children frequently move their heads
several times from side to side, as we do in shaking our
heads in negation.
When we follow Darwin’s argumentation, a child, when hungry, starts to search
instinctively for its mother’s breast and begins to suck (although this process is usually
referred to as “sucking” it actually consists of squeezing the milk out of the breast). The
searching and sucking start automatically by inborn mechanisms called therooting
reflexand the sucking reflex, respectively. The rooting reflex finds expression in the
fact that the baby will turn its head toward anything that touches its cheeks or lips. The
sucking reflex finds expression in the fact that as soon as something touches the baby’s
palate, the baby inevitably starts sucking. These reflexes begin to develop in the third
month of fetal existence and are already present at birth (Smith et al., 1985).
Once the baby has satisfied its needs and would like to stop drinking, it has to
start an avoidance behavior. An avoidance behavior is necessary because the sucking
reflex prevents the baby from simply stopping the sucking/drinking. This means the baby
must use its head; this appendage is chosen because small babies lack the ability to
fully control their hands and arms. To elude the breast the baby has several possibilities,
depending on the breastfeeding position. In most cases, however, a backward head toss
is not possible because mothers usually hold the baby’s head to support the weak neck
muscles and lack of motor control, as depicted in Figure 1. The figure shows some of
the most widely employed breastfeeding positions. In the positions A to C, it is
impossible to move the head back, and the only escape is a lateral one. The picture in D
shows a breastfeeding position where it is possible for the child to move the head back,
but even in this case the easier motion would be a sideways one. Note that similar
claims can be made for children who are not breastfed, but bottle-fed.
Figure 1: Common breastfeeding positions (see, for example, Meek, 2017)
Interestingly, newborns are unable to hold their heads in an upright position very long,
but are nevertheless able to perform active side-to-side movements, at least
occasionally, as early as five days after birth (Prechtl, 1989). Indeed, the fetus is already
capable of turning the head to the side from about 18 weeks onwards (De Vries, Visser
& Prechtl, 1982). Additionally, there is more range horizontally than vertically, i.e., it is
easier to move the head to the side than to move it up or down. It seems plausible that
when this behavior is repeated several times in early childhood, a connection between
refusal and the horizontal head movement is establishedmaybe via Hebbian cell
learning, i.e., via establishing neural connections between neural networks that are
repeatedly active together at the same time.
As well-founded as this argument sounds, it seems hard to come up with an
empirical way to test this hypothesis. Even if there is no way to test Darwin’s idea in an
empirical way directly, it is possible to think of its consequences. Indeed, Darwin’s
hypothesis makes several predictions:
i. The experiences with breastfeeding described by Darwin should be very
similar across cultures. From this, it follows that the headshake should be used for
refusal/negation in a similar way across cultures. In other words: headshakes should be
the most widespread means of expressing non-verbal refusal/negation as there is a
experiential connection between the two. However, as this connection is not innate and
only a natural connection between the movement and the concept of refusal exists, it is
in fact expected that it is easily possible to culturally overwrite this form-meaning pair.i
ii. Because the rooting and the sucking reflex start very early, the connection
between the lateral head movement and negation/refusal should be established very
early as well. Consequently, the headshake as a gesture for negation (or refusal) should
be acquired very early.
iii. Because of the way the connection between the head movement and the
concept of refusal is established, even deaf-and-blind-born children should shake their
heads when expressing negationeven though they cannot have observed this
behavior themselves (at least not directly).
iv. The same connection should be established in other mammals who
breastfeed in a similar way.
Each of the four predictions is a hypothesis on its own. In the remainder of the paper I
will try to review the available evidence which could possibly speak in favor or against
each prediction. To anticipate the conclusions: the available data points into the direction
that predictions (i) and (ii) turn out to be on the right track while the available evidence
for predictions (iii) and (iv) is rather weak.
3 Prediction I: the prevalence of the negative headshake
The goal of this section is to review the evidence available concerning the worldwide
distribution of the negative headshake. As systematic studies of the geographical or
cultural distribution of head gestures are rather scarce, this section will discuss several
sources of evidence. First, some general remarks on different types of universals will be
made. Section 3.1 gives a brief overview of different head movement systems. Section
3.2 finally takes the most varied sources of evidence into account which can give us
hints about the geographic spread of the negative headshake.
According to Darwin’s hypothesis, the connection between refusal (and later
negation in general) and shaking the head is grounded in real-world experience. As this
connection should be established independently in all humans, this natural association
between a mental concept and a body movement should be found all over the world
across cultures, i.e. it should be a universal. However, as this connection is not innate,
but only develops through some kind of natural process, it is still possible that a culture
might use different means to express negation. Thus, the negative headshake is
predicted to be a statistical rather than an absolute universal. In linguistics, statistical
universals are usually explained in terms of “how languages develop, how they are
used, how they are learned, and how they are processed (Bickel, 2011, p. 78). The
explanation offered in this article follows this tradition, and it is claimed that the
headshake is used because of how negation and negative gestures develop in the spirit
of Darwin. In those societies where the negative headshake is not used, it is assumed
that it is continually overwritten by some other specific cultural practice.
The idea that the negative headshake constitutes a near or statistical universal
and the idea that it has some kind of natural or embodied origin are strongly connected.
However, some authors claim that it is not possible to state that head gestures in
general have a somehow motivated origin as Darwin did. Wagner, Malisz & Kopp (2014,
pp. 215–216), for example, refute a motivated origin of head gestures as they do not
constitute universals:
However, the possible iconic or universal nature of the
relation between e.g. nodding and agreement cannot be
postulated, since some well-known reversals exist. In
Bulgarian (Jakobson, 1972), where a head upstroke means
“no” and in some cultures of the Mediterranean (Greece,
Southern Italy, the Balkans) where throwing the head back is
associated with negation (Abercrombie, 1954; Jakobson,
1972). The head bobble or waggle, referring to repeated,
side-alternating head tilting, is a characteristic head gesture in
India, unknown in Western cultures, used to express
backchanneling, friendliness and acceptance.
This is an interesting assessment. When looking at similar cases where we find a great
uniformity across cultures, researchers usually do not state that it is impossible to find a
motivated origin of such uniformity just because there are exceptions. A prime example
is informal kinship terms, which show striking cross-linguistic phonological similarities
that usually include a bilabial nasal and an a-like sound for the word for mother as in the
English word mama and a similar word for father starting with a plosive as in papa.ii An
explanation of this uniformity is that children’s phonological development follows cross-
culturally stable patterns as argued by Jakobson (1962) in a now famous paper.iii There
is substantial support for this hypothesis, although it is not hard to find languages with
completely dissimilar words for mama and papa: in Georgian the reverse pattern is
found with the word for mother being deda and the word for father being mama. Another
example of a language not following the general pattern is Warao, where the informal
word for father is dima and for mother dani (Heinen, 1972). Here we do not simply find a
reversal, but both words begin with a plosive and a different vowel is used as well.
It is not farfetched to compare the informal kinship terms to negative head
gestures. As with the informal kinship terms, we find great uniformity in the world’s
cultures. As with the words for mama and papa, we find rare exceptions of this
uniformity. Sometimes we find reverse systems in which a nod is used in negative and a
shake in positive contexts (the analogy being Georgian deda and mama). Sometimes
we find systems in which a different pattern is found, where a different axis is used as
can be observed with the head wobble or a backward head toss (the analogy being
Warao dima and dani).
For the informal kinship terms, the exceptions found can be simply explained by the
well-known fact that the connection between form and meaning is arbitrary (Saussure,
1916)which of course does not exclude motivation. It is plausible that even words that
have some kind of natural origin can be culturally overwritten with an arbitrary form. The
same should be true for the negative headshake. What follows from this explanation is
that a connection between a side-to-side movement of the head and negation could be
established independently in different places and timesfinally becoming a
conventionalized gesture used by a whole community. It does not exclude the idea that
this connection cannot possible be culturally overwritten by another gesture system. The
idea of such an overwriting is supported by the narrow geographical distributions of
systems not using a negative headshake, plus the dispersion of the negative headshake
in so many culturally unrelated regions in the world, as I will discuss next.
3.1 Different head movement systems
Different cultures of the world use different head movements to express epistemic
stance. Usually, two distinct head movements exist for the most extreme ends of the
epistemic spectrum: one for negation and one for affirmation. Three different systems of
head movements to express epistemic stance are traditionally distinguished in the
literature: System A, System B, and System C.
Probably the most common system is labeled System A by Jakobson (1972) (for
a short overview of its use, see also Kendon, 2002). The system consists of a lateral
headshake for negation and a vertical nod for affirmation. The opposite system is called
System B. In this system, a side-to-side headshake is used for affirmation and a vertical
nod to indicate negation. Often a third system, System C, is distinguished. In System C
affirmation is signaled by a nod or a single head dip forward while negation is expressed
by a single backward head toss, often accompanied by a single tongue click (an apical
alveolar click). Jakobson’s distinction is summarized in Table 1.
System A
Lateral head movement (headshake)
Vertical head movement (head nod)
System B
Vertical head movement (head nod)
Lateral head movement (headshake)
System C
Vertical head movement (head toss)
Vertical head movement (head nod)
Table 1: The three head-movement systems used for negation and affirmation according to Jakobson
3.2 The distribution of the systems
The goal of the following paragraphs is to show that despite the lack of systematic
studies on the distribution of different systems, it is possible to state that System A is
prevalent in most cultures around the worldat least concerning the negative
headshake. This can be seen by studying the gesture systems themselves, by looking at
sign language data, or by looking at (historical) data on manual communication systems
that include head movements.
3.2.1 Headshakes in spoken languages with System A
Unfortunately, there are nearly no comprehensive studies on where exactly System A is
used. Nevertheless, many studies on negative headshakes exist. The goal of this short
section is to list mentions of the use of negative headshakes in different
countries/cultures: at least today, System A is used in nearly all Western cultures
including Europe, Australia, and the US (e.g., McClave, 2000). The literature additionally
mentions the use of negative headshakes as gestures among hearing people in China
(Li 2019), India (Rose, 1919; Vaidyanathan 1991), Taiwan (Chang & Wang 2009),
Columbia (Saitz & Cervenka 1962), Kenya (Creider 1977), Japan (Hamiru-aqui 2008),
Australia (Anderson et al. 2008), Russia, the Czech Republic, Poland (Jakobson 1972),
France, Germany (Vávra 1976), Syria, Libya, Jordan, Saudi Arabia, Lebanon, Kuwait,
Egypt (Barakat 1973), Sweden (Andrén 2014), Thailand (Zlatev & Andrén 2009), Italy,
and Britain (Kendon 2002). This is a surprisingly short list assuming that someone who
might encounter a system in which the headshake is not used for negation would with
certainty write about communicative problems with this culture mentioning that she or he
uses negative headshakes, while others do not (or the other way around).
While the literature cited above consist of more or less isolated mentions of uses of a
negative headshake, there is one large comparative study on gestural similarities and
differences across cultures which also considered headshakes. Matsumoto & Hwang
(2012) presented videos of gestures, including headshakes and nods, to participants
from East Asia (China, Japan, and South Korea), Latin America (Mexico, Guatemala, El
Salvador, and Brazil), Africa (Kenya, Ghana, Nigeria, and Niger), South Asia (India,
Pakistan, and Nepal), the Middle East (Syria, Turkey, Jordan, Afghanistan, Lebanon,
and Egypt), and Western cultures (USA, Germany, and Canada). Participants were
asked about the intended messages of the gestures shown to them in their respective
cultures. Matsumoto & Hwang’s (2012) results show that 99.10% of their 516
participants recognized the headshake as a gesture expressing disapproval (and
98.18% recognized a head nod as a gesture of approval). This, again, can be
considered strong evidence of the extreme prevalence of System A in the world’s
cultures. A summary of countries from which the use of a negative headshake was
reported is shown in Figure 2.
Figure 2: Countries in which the use of a negative headshake was reported in the literature.
3.2.2 Headshakes in sign languages
The domain of non-manual markings, especially the domain of negative head
movements, in sign languages is well-investigated for a variety of typologically and
geographically distant sign languages. This has led to an asymmetrical development in
sign language and gesture research: there is more information available on negative
head movements in sign languages than there is data on negative head gestures used
by hearing people. Thus, it makes sense to look at sign language data because most
sign languages of the deaf developed when surrounded by a hearing culture. It is
generally assumed that grammaticalized non-manual forms, such as (negative)
headshakes, are adapted from the hearing culture (Meier, 2002, p. 13; Sandler, 2009, p.
945; Pfau, 2015), so this kind of data can tell us something about the gestures used in
the particular area in general.iv
In her study on 38 typologically and geographically distant sign languages from all
continents, Zeshan (2004) observes that all 38 use a headshake in sentential negation
(see also Zeshan, 2006; Sandler & Lillo-Martin, 2006, p. 358; Quer, 2012)although in
some it is obligatory and in some it is not. However, also sign languages in which the
headshake is not an obligatory marker of negation exhibit negative headshakes:Even
sign languages that use other head movements also have a side-to-side headshake in
addition to the other possibilities(Zeshan, 2004, p. 11). Of special interest are cases in
which the surrounding society does not use System A. In the Eastern Mediterranean
region, for example, a negative head toss is used in both the sign language and by the
surrounding hearing culture. This is the case for Lebanese, Jordanian, Turkish, and
Greek Sign Language. These sign languages, however, also make use of a negative
headshake (Zeshan, 2004; 2006; Antzakas, 2006; Quer, 2012). Additionally, in some
areas where the backward head toss is used in the hearing culture, it is completely
absent in the sign language, and a negative headshake is used instead. This is the case
in Italian and Israeli Sign Language (Hendriks, 2007). In whatever way the headshake
may have entered the respective sign language, Zeshan’s data indicates that the
headshake is prevalent all over the world, even in areas where the negative headshake
is (claimed to be) not used by the surrounding hearing culture. This is at least true for
those sign languages included in Zeshan’s study used in areas where System C (e.g.,
Italian Sign Language) is prevalent. The situation for sign languages used in regions
where System B is used is less clear.v
Figure 3: Overview of the sign languages under discussion in Zeshan’s (2004) typological study. All sign languages
in this map make some use of a negative headshake. Each star in the map represents a country in which one of
the sign languages is used.
An overview of the sign languages included in Zeshan’s study is given by the map in
Figure 3 (a list of the sign languages is additionally given in the appendix). As can be
seen, a headshake is used in sign languages all over the world, corroborating the
assertion of a negative headshake as a quasi-universal. Although Zeshan’s study did not
explicitly look at how refusal is expressed, given what is known about sign languages, it
is likely that refusal is expressed by a combination of a manual sign plus a headshake in
most sign languages (see, for example, the study on American Sign Language by Fisher
2006). However, even if the sign language data discussed so far is concerned with truth-
conditional negation, I will argue that during language (as well as gesture) acquisition
the semantics of the expressions for negation expand from refusal to a more broad
concept of negation (see Section 4).
3.2.3 Headshakes in alternate sign languages
Apart from those sign languages that are full-fledged natural languages, many manual-
gestural communication systems evolved in various cultures for different purposes which
are called alternate sign languages(Kendon, 1988), secondary sign languages(e.g.,
Pfau, 2012), gestural (communication) systems(Goldin-Meadow & Mylander, 1984), or
kinesic codes(Kendon, 2004). In some cases such alternate sign language evolved
due to a vow of silence (e.g., monastic sign languages), while in other cases oral
communication was impossible due to noise (e.g., sawmill sign languages) (see Pfau,
2012). Finally, some alternate sign languages evolved to overcome speech barriers.
This is documented, for example, in Plains Indian Sign Language (PISL), an
interlanguage which was used in the United States and Canada. PISL is an interesting
case to discuss here, because it may offer a possibility to gain insight into the gesture
system used by Native Americans before European contact. While it is not clear how old
PISL actually is, evidence suggests that it existed long before European contact
(Wurtsburg & Campbell, 1995). It would be further support of the idea of the negative
headshake as a near universal if PISL usersconstituting a vast array of different
subcultures cut off from the influence of Western cultureshad used a negative
headshake. Nineteenth century descriptions of PISL indicate that it indeed used a
negative headshake (Clark, 1885, p. 271). There are also many reports of early
European travelers making notes on PISL, but in none of them is it mentioned that they
would make use of unusual head movements for negationother unusual
characteristics, e.g., that many Native Americans used tongue clicks when speaking, on
the other hand, are directly mentioned in these reports (see Wurtsburg & Campbell,
1995 for details). While it is still possible that the headshake may have entered the
system only later due to contact with Europeans, this is rather unlikely. Thus, it could be
assumed that System A was used in this area as Clark (1885) also reports positive head
nods. The same is true for similar alternate sign languages used by various native tribes
in Australia, at least when it comes to the negative headshake (Cameron, 1881, p. 4, as
cited in Kendon, 1988, p. 39).
Hence, even in those manual communication systems which developed
independently in unrelated cultures on different continents (and before these cultures
had contact with Western gesture systems), the headshake as a sign for negation has
been documented. It can be inferred that, most likely, System A was used in North
America and Australia (or at least in parts of it). Now that sign languages of the deaf and
manual-gestural communication systems have been discussed, the next section is
devoted to head movements used for negation different from headshakes accompanying
spoken languages.
3.2.4 Headshakes in spoken languages with System B and C
System A seems to be, as argued in the previous subsections, the most common one.
The opposite system, however, System B, is also found in some societies. It is, for
example, found in Bulgaria. This system may be rare but it is found not only in Bulgaria,
but also in neighboring territories, e.g., in Kosovo, Macedonia (e.g., Hentschel, 1998),
Albania, and in more distant regions such as Afghanistanhowever, systematic studies
of the spread of System B in these countries do, to the best of my knowledge, not exist
(but see the study by McClave et al. 2007 who study head movements in different
cultures, but from a backchanneling perspective). Additionally, there is one (rather
vague) description of a positive headshake used among Sinhala speakers in Sri Lanka
(Premavardhena, 2007) and mentions of the use of the head bobble in India (Wagner,
Malisz & Kopp, 2014). Even if this is the only report, I will treat the Sinhala community as
belonging to System B until counter-evidence becomes available.
The third system, System C, will be discussed in some detail here because it will be
argued that it in fact also exhibits negative headshakes. Again, this system displays
narrow geographical limitations, being found, for example, in Greece, Turkey, and
Southern Italy (Morris et al., 1979; Collett & Chilton, 1998; Kita, 2009). Although the
literature reports that a backward head toss is used in those areas, it does not seem to
simply replace the negative headshake, but both rather exist simultaneously serving two
similar but still distinct functions: the headshake is used as a truth-conditional operator,
while the head toss is a marker of refusal as will be shown in the following.
In all three countries, i.e., Greece, Turkey, and (Southern) Italy, backward head
tosses are used as negative gestures along with negative headshakes. Indeed, a head
toss and a headshake can be used with the same utterance, as exemplarily depicted in
Figure 4. The figure shows a native speaker of Greek uttering the sentence in (1).
(1) Oxi re den thelo
NEG anyway NEG want-1SG
‘No, I don’t want that.’
Figure 4: A Greek woman performing a backward head toss and a headshake while uttering Oxi re den thelo (‘No,
I don’t want that’).
The backward head toss is used as a marker of anaphoric negation (oxi)—i.e., a
negation that is used to object to a previous utterance and as a link to the
discourse—and the headshake as a marker of sentential negation simultaneously
with the negated VP (den thelo). It seems plausible to view the head toss as a
negative response to a question and the headshake as a marker of sentential
negation which can be produced across VPsand also across longer VP strings
because of its continuous character. Thus, the backward head toss and the
headshake are not only formally, but also functionally The native
speakers I consulted (i.e., native speakers of Greek, Turkish, and Southern
Italian, all born and raised in their respective countries) agreed that a negative
head toss only over the verb (the translational equivalents of want) in a sentence
like the one in (1) would result in an unnatural utterance. By contrast, all would
accept the sentence with the backward head toss on the sentential negator only.
In this case, the sentence, again, gets a rejection reading.
An additional method of providing evidence for the claim that System A is the
most common is to investigate those areas where System A is not implemented. If
we assume that there are areas in the world where a head gesture different from
the headshake is used in negative contexts, we would expect many reports of
such gestures in (Western) literature because it should be more likely to report a
system deviant from one’s own than a familiar one. Interestingly there are not
many such reports. Additionally, a closer look at these reports reveals that they
refer to a limited set of cases.
Figure 5: Countries for which it was reported that System A is not used.
The literature reports that a system different from System A is used in some
countries in the Mediterranean region and in the Middle East. The map in Figure 5
shows those countries. As can be seen, System C was reported to be used only in
Greece, Southern Italy, Turkey (Morris et al., 1979), Lebanon, Jordan, and Israel
(Hendriks, 2007). System B is used only in Bulgaria, and maybe in Macedonia, Albania,
Kosovo, Afghanistan, and possibly by Sinhala speakers in Sri Lanka. Although there is
not much data available about where exactly System A is used, the distribution of the
other systems shown in the map suggests that it is used in nearly every part of the
Interestingly, most countries in which a system different from System A is used form
geographic clusters, as can be seen on the map. On the whole, there is a surprisingly
small number of cases where System A is not used, or to be more precise, where head
gestures other than a negative headshake were reported. This is especially true if one
takes into account that the probability that such deviations would be reported, for
example by travelers, should be very high. Additionally, a report of a negative head
gesture different from a negative headshake does not imply that a negative headshake
is totally absent in the respective culture (as argued for the cases of Turkey, Greece,
and Southern Italy). Taken together, a negative headshake can be found in almost all
cultures of the world.vii
4 Prediction II: early acquisition of the headshake
As argued above, the headshake as a gesture expressing negation should be acquired
very early. Indeed, the first expression of negation in young children is a side-to-side
movement of the head, which is used at around the age of 1 year and 1 month for the
purpose of refusal. This renders the headshake one of the first gestures to be acquired
(Bates et al. 1979; Eriksson & Berglund 1999; Guidetti 2005; Zlatec & Andrén 2009;
Benazzo & Morgenstern 2014). Only later on, between 1 year and 3 months to 1 year
and 5 months, do they start to produce verbal expressions for negation (Pea, 1980;
Fenson et al., 1994; Guidetti 2005). Interestingly, children tend to use the lateral head
movements almost exclusively for rejection, and not in a truth-conditional sense as
adults do (Bloom, 1970; Pea, 1980; Guidetti, 2005; Fusaro, Harris & Pan, 2012). Later
on, the semantics of the headshake extends from rejection to other uses of negation,
including truth-conditional onessimilar to the development of spoken negative
expressions which are also first used for rejective and only later on for truth-conditional
purposes (see e.g., Stern & Stern, 1907, p. 236; Bloom, 1977; Pea, 1980; Choi, 1988;
Hummer, Wimmer & Antes, 1993; Dimroth, 2010). This was shown for example in a
study by Fusaro, Harris & Pan (2012) studying 14-, 20-, and 32-month-old children. They
found that the headshakes of the 14- and 20-month-olds predominantly conveyed
refusal, and that this usage strongly declined in 32-month-olds. Thus, the repertoire for
which the headshake can be used expands to more negative categories. This is in line
with Darwin’s idea that the headshake is rooted in refusal. A similar observation was
made for sign languages, which suggests that they follow the same path as hearing
children: the first function of negation being refusal expressed by a headshake. Then the
concept of negation expands to other uses, including truth-conditional ones, which are
not expressed using gestures, but by using language (in the case of sign language
users, this is either also a headshake or a manual sign, acquired around 18 and 20
months, see Anderson & Reilly, 2002 and Reilly & Anderson, 2002). Finally, the
headshake can be used to express these functions too.
Following this logic, the development of the negative headshake would be like the
following. First, children naturally turn their head to the side to refuse food-intake. An
instructive example of this behavior comes from a 12-month-old toddler from a diary
observation study by Kettner & Carpendale (2013: 199):
She always rejected food by turning her head to the right (and only
to the right). She used to cry while she did it, but now it’s just a
quick head jerk to the side and I know she’s not going to eat it.
In repeating this process time and again, a connection is established between refusal
and the head gesture. Later in life, the gesture is expanded through reduplication
(probably as a means of intensification) to a repeated side-to-side movement. As this is
a learning process, the linking of the headshake and refusal may take some time. As
reported by Kettner & Carpendale (2013, p. 205): “There is […] some developmental
distance between a head turn and shaking the head”. This process, of course, is a
simplification because there will always be an influence by observing grown-ups using
the headshake as a gesture of negation (an issue that will be addressed in the next
section). It seems as if it not only takes time to establish a connection between refusal
and the headshake (cf. Kettner & Carpendale, 2013), but it also takes some time to
establish a connection between other semantic functions of negation and the headshake
as suggested by the results of the gesture and language acquisition studies cited above
(Bloom, 1977; Pea, 1980; Choi, 1988; Hummer, Wimmer & Antes, 1993; Anderson &
Reilly, 2002; Reilly & Anderson, 2002; Dimroth, 2010). Such functions include responses
to questions or syntactic uses (Fusaro, Harris & Pan 2012, p. 446 give the following
examples for these uses: “using a Cookie Monster puppet, mother asks ‘Do you have
any cookies little boy?’ Child shakes head ‘no’” and “playing with a toy house, child
shakes his head while static, ‘That room doesn’t have, um, any toys’”).
Taken together, the prediction that the headshake is acquired early in life turns out to
be correct. What is unclear, however, is what happens with individuals growing up in a
System B environment. If Darwin’s hypothesis is on the right track, then we would
expect the connection between the headshake and refusal/negation to be present in
those individuals too.
5 Prediction III: headshakes in humans born deaf-and-blind
If the headshake is acquired as described by Darwin, then it should also be used as a
negative gesture in deaf-and-blind-born individuals who never had the chance to
observe the gesture. In addition, the absence of auditory input prevents them from being
told about gesture usage. In an early study on gestures in congenitally deaf-blind
children, Goodenough (1932, p. 328) notes:
While the behavior of such cases is unquestionably affected by the
results of their own experience, this experience does not include
observation and imitation of the behavior of others, nor, previous to
training in language, can any except the most primitive and
essential standards of behavior be communicated to them.
If Darwin’s line of thinking is correct, the negative headshake should not only be
observable in blind (where headshakes are found; cf. Iverson et al., 2000), but also in
deaf-and-blind individuals. The available evidence for this claim reported in the literature
will be discussed in this section. In one study examining a 13-year-old congenital deaf-
and-blind girl, who had some residual hearing ability, headshakes could indeed be
observed (Deasy & Lyddy, 2009). This study reports that the girl could answer simple
questions like “Do you want a drink?” using nods and headshakes (due to the residual
hearing it was possible, in this case, to communicate to a limited extend via language).
Of course, of more interest are those cases where the individuals under consideration
do not have any residual hearing.
This was the case in an early study by Goodenough (1932), who reports headshakes
as an aversive reaction in a 10-year-old deaf-and-blind-born girl. Eibl-Eibesfeldt (1973),
studying the behavior of 7-year-old blind-and-deaf-born Sabine, also reports the
observation of headshakes as a sign of refusal (linguistic communication was not
possible in these cases):
[…] Sabine could be made angry either by repeatedly offering a
disliked object or by persisting in social contact attempts when
she was not willing. She would then turn away abruptly, shaking
her head from side to side, finally jerking it backwards, closing
her mouth firmly and sometimes biting against her lower lips or
clenching her teeth. (Eibl-Eibesfeldt, 1972, p. 180)
These studies seem to indicate that headshakes are not a form of behavior that is
learned through observation. The existence of System B furthermore suggests that it is
not a reflex-like innate behavior (and can be culturally overwritten). Thus, at first sight,
one could conclude that those reported uses of headshakes in deaf-and-blind-born
individuals have some kind of natural originas the one proposed by Darwin. Also in
line with Darwin, the reported headshakes are used for refusal. One problem with the
reported studies is, as the reviewers correctly remarked, that the children were rather old
(10 and 7) and the possibility that they were implicitly (or even explicitly) taught to use
negative headshakes cannot be excluded. This means that the negative headshake
could also have entered the children’s communicative system as a co-construction
through dialogue. Thus, more studies in this domain are clearly in need.
6 Prediction IV: headshakes of other mammals
Most nonhuman mammals, e.g., pigs, are breastfed when the mother is either lying on
her side or standing, as depicted in Figure 5B and 5C. These animals therefore do not
need to perform a horizontal head movement to stop the feeding. It is sufficient for them
to lower their heads, a movement supported by gravity (or they can simply step back, if
possible). The special posture of human babies, in contrast, makes non-lateral head
movements difficult. There are, however, other nonhuman mammals that breastfeed
their babies in a similar way. An example for these mammals is bonobos (Pan
paniscus), as shown in Figure 5A. Following Darwin’s argumentation, and provided that
bonobos are able to understand and use some form of negation, they should also shake
their heads, or more broadly, use lateral head gestures, for negation. The latter
assumption can be made, at least when it comes to the most simple function of
negation, namely in contexts where the animals want to make an effort to prevent others
from engaging in some sort of behavior (which can be argued to be a kind of refusal).
Figure 6: A bonobo mother breastfeeding her child. B and C: Pigs, as well as most mammals, breastfeeding their
children either in a lying or standing position
Breastfeeding behavior similar to humans is found in many apes and monkeys. Two
cases can be distinguished when looking at these apes and monkeys. Those from which
no lateral head gestures were reported and those from which lateral head gestures
where reported. If lateral head gestures are reported further distinctions can be made
regarding their communicative functions. The head movements may: (i) serve unclear
functions/have unclear meanings, (ii) may have non-negative meanings, or (iii) may
serve as more or less clear negative communicative signals. In general, non-human
primates who breastfeed their babies in a similar way as humans include the great apes
(orangutans, gorillas, chimpanzees, and bonobos), the lesser apes (gibbons), Old World
monkeys (e.g., mangabeys), New World monkeys (e.g., capuchins), and lemurs.
Non-human primates which breastfeed their babies in similar ways as humans from
which, to the best of my knowledge, no headshakes were reported in the literature
include orangutans and the species of lesser apes (gibbons). To be more precise, head
gestures in general seem to play no role in the communicative behavior of orangutans
(Pongo pygmaeus) (Liebal, Pika & Tomasello, 2006; Cartmill & Byrne, 2010). The
situation is similar to the various species of lesser apes (Hylobatidae), where the few
studies available contain no reports about headshakes or turns (see, for example,
Tomasello & Call 1997; Libal, Pika & Tomasello, 2004). It has to be stressed, however,
that there is still not much known about the communicative behavior of apes and
monkeys, especially not under natural conditions (cf., for example, Tuttle, 2014).
Although there are no reports of lateral head movements from organutans and lesser
apes, there are reports from Great apes (e.g., bonobos), Old World monkeys (e.g.,
mangabeys), New World monkeys (e.g., capuchins), and lemurs. In the following, I will
discuss lateral head movements with unclear meanings, those with non-negative
functions, and finally those with negative functions. However, the line between non-
negative and negative functions remains unclear as there is room for interpretation
concerning the question of what counts as a negative meaning.
Lateral head movements with unclear functions were observed in chimpanzees and
gorillas. Kortlandt (1969) and Waal (1982) both report headshakes in chimpanzees, but
stress that humans influence could not be excluded in their studies. Hobaiter & Byrne
(2011), however, also report headshakes in wild chimpanzees, but again their intention
remains unclear. Similarly, Tanner et al., (2006) report headshakes from gorillas living in
zoos and in the wild, but again with unclear intentions (see also Pika, Liebal, &
Tomasello, 2003; Genty et al. 2009; Tanner & Perlman, 2017). Tanner et al. (2006) also
mention, however, head turns as an avoidance behavior at least in zoo-kept gorillas.
While avoidance behaviors could be interpreted as negative (see below) some non-
human primates seem to use lateral head movements for non-negative functions. The
most prominent function is solicitation. Wild capped langurs, for example, were reported
to use headshakes as part of solicitation behavior (e.g., Solanki, Kumar & Sharma,
2007). Additionally, headshakes to solicit play were reported in many African great apes,
including chimpanzees (van Hoof, 1973), gorillas (Tanner et al., 2006), and bonobos
(Pika, 2007).viii
While lateral head movements to signal truth-conditional negation seem to be absent
in apes and monkeys there are some functions of the headshake in non-human
mammals which can be interpreted as having some negative function. As already
mentioned above, zoo-kept gorillas were observed to use head turns as an avoidance
behavior. Similar observations come from other species. Ruffed lemurs, for example,
were observed to use head turns as a submissive behavior, probably as a means to
avoid eye contact (Pereira, Seeligson & Macedonia, 1988). This fits in well with the idea
that the origin of the headshake lies in some sort of avoidance behavior (cf. Jakobson,
1970; Vavra 1967 and Section 2). The same behavior is found with some New World
monkeys (Ceboidea): Eyebrow lowering […] occurs in many of the Ceboidea, from
marulosets such as Oedipomidas to the advanced capuchins […] during friendly but
hesitant approaches to a fellow and in similar situations. It is commonly accompanied at
intervals by lateral head shaking and by eye closure. In capuchins, in particular, the
resemblance of such a display to the full pattern of protective responses elicited by a
nauseous taste, for example, is marked” (Andrew 1963, p. 1035). The clearest cases of
negative lateral head movements, however, come from bonobos. Zoo-kept bonobos
were observed to shake their heads to signal negation (or a precursor of negation) in
preventative situations (Schneider, Call & Liebal, 2010; Pinfield, 2013). This was, for
example, observed when mothers were trying to prevent their children from performing a
certain behavior, e.g., to stop them from playing with a plant (I also refer the reader to
the supplementary files in Schneider, Call & Liebal, 2010; Pinfield, 2013 which include
video materials):ix
Example 1: The mother and her female offspring were sitting
next to each other on the ground. The offspring started crawling
away toward a nearby tree trunk and proceeded to climb. The
mother retrieved the infant and positioned her back to her side.
The infant made continual efforts to climb the trunk, and each
time the mother retrieved her. This culminated in the mother
seizing the infant by the leg and shaking her head while looking
toward her. The infant climbed once again, this time moving
around the tree (now out of sight of the mother). After awhile,
the mother got up, moved around the tree, grabbed the infant’s
arm, and pulled her to the place where they originally sat. When
releasing the infant the mother looked at her and shook her
head once more. The mother started grooming another group
member, and the infant moved toward the tree again.
Example 2: The mother and her female offspring were sitting
next to each other on the ground while the infant manipulated a
piece of leek. After awhile, the mother took the leek from the
infant and threw it to the side. Eventually, the infant retrieved
the leek and the mother tried to recapture it. The mother shook
her head twice while doing so and threw it away from her again.
The infant continued to move toward the piece of leek.
(Schneider, Call & Liebal, 2010; Pinfield, 2013, p. 200)
Everything considered, we have evidence that there are some non-human mammals
that breastfeed their young in a similar way to humans, using lateral head movements
also in what can be called negative contexts. The literature on great apes refers to these
gestures as being used in preventative contexts. As illustrated by the examples cited
above, this means that the ape shaking its head seems to have the intention to stop
another ape from performing an action. This may not be exactly an action of refusal, but
it is nevertheless in line with Darwin’s idea. However, according to Darwin’s hypothesis
one would have expected more reports on non-human primates using headshakes also
in contexts different than prevention. On the other hand, there is, to the best of my
knowledge, no report on mammals, that breastfeed their young in a lying or standing
position, explicitly displaying negative headshakes. Thus, the literature on apes and
monkeys at least partly supports Darwin’s hypothesis; although it does not present very
strong evidence, the missing reports on headshakes in orangutans and other apes and
monkeys do not directly speak against it. One open question relates to the question why
headshakes have been reported in preventative situations, but not as a sign for refusal
in other situations (e.g., when offered something that they do not want). One tentative
answer to this question may, as correctly pointed out by a reviewer, be that apes often
do not have the need to communicate refusal as they might simply not participate in a
joint action or can just ignore an offered object.
7 Conclusio ns
The goal of this paper was to look at the predictions made by the hypothesis that the
headshake as a gesture of negation has its origin in early childhood experiencesan
idea going back to Charles Darwin who speculated that the connection between
negation and the headshake stems from early childhood experiences of turning the head
away in order to stop food intake. The predictions looked at were: (i) that the headshake
should be found in nearly all cultures of the world, (ii) that the headshake should be
acquired very early in life, (iii) that it should be found as a gesture in individuals being
born deaf and blind, and (iv) that the headshake should be found in non-human
mammals being breastfed in a similar way to humans.
Concerning the prediction that the headshake should be the most wide-spread
gesture for negation, the available evidence suggests that this is indeed the case, i.e.,
negative headshakes are found all over the world, although some rare exceptions exist.
These exceptions, however, do not speak against Darwin’s hypothesis as it is not
unexpected that the negative headshake can, in some cases, be culturally overwritten
by other gestures. The second prediction is also supported by the information available.
The headshake as a gesture of refusal/negation is indeed one of the earliest gestures
acquired by human children. While the evidence for the first and the second hypotheses
is in line with Darwin’s idea, the situation is much less clear with the other two
predictions. The data available from deaf-blind individuals on the one hand supports
Darwin’s idea as negative headshakes are found in these individuals. The data is, on the
other hand, very scarce and from the descriptions available, the possibility that the
headshake entered the gestural repertoire of deaf-blinds by implicit or explicit instruction
cannot fully be excluded. Similarly, the evidence available in favor of the fourth
prediction, namely that non-human mammals being breast-fed in a similar way as
humans also use headshakes for similar negation-related functions is scarce. The
clearest case discussed were bonobos shaking their heads to prevent others from
performing an action. When it comes to other apes and monkeys the evidence is,
however, at best mixed. While some non-human primates were reported to use lateral
head movements, their exact function often remains unclear and for others no reports
exist at all. While this is not great support of this prediction, it does, however, also not
constitute counter-evidence.
While the first and the second predictions have been looked at in isolation, this paper
is the first discussing the third and the fourth prediction in relation to Darwin’s hypothesis
and the first trying to bring together as much evidence as possible in support of it. The
discussion presented furthermore underlines the problems which come with Darwin’s
hypothesis. Not only is it hard to come up with empirical ways to test it directly, but the
predictions it makes are also not unproblematic as evidence against the predictions will
not suffice to reject the hypothesis (although the predictions, in general, seem to be
more or less correct). The paper also unveiled that there are several research gaps
which need to be addressed before it can be really stated that all the predictions are
completely met or not: large-scale cross-cultural comparisons of the use of head
gestures are still rare and in great need. More research on the use of gestures in
congenitally deaf and blind individuals needs to be done, especially with young children
and more research on the use of lateral head movements in non-human mammals and
their meanings would also be highly welcome.
Taken together, the presented discussion suggests that the negative headshake is a
statistical universal acquired very early in life that is also used by individuals who have
not had the opportunity to directly observe it (i.e., congenitally dead-blind individuals)
and leastways by some non-human primates in a similar way as humans. This, at least
partly, supports the idea that the headshake as a gesture of negation has its origin in a
natural behavior in early childhood. This is in line with research suggesting that many
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Appendix: List of Sign Languages Used in Zeshan (2004)
American Sign Language (ASL): United
States and Canada except Quebec
Auslan: Australia
British Sign Language (BSL): UK
Chilean Sign Language: Chile
Chinese Sign Language: mainland
Dansk Tegnsprog: Denmark
Deutsche Gebärdensprache (DGS):
Finnish Sign Language (Suomalainen
iittomakieli): Finland
Greek Sign Language: Greece
Hong Kong Sign Language: Hong Kong
Íslenskt táknmál (Icelandic Sign
Language): Iceland
Indo-Pakistani Sign Language (IPSL):
India and Pakistan
International Sign
Irish Sign Language: Ireland
Israeli Sign Language: Israel
Kata Kolok: Bali
Kenyan Sign Language: Kenya
Langue des Signes Française (LSF):
Langue des Signes Quebecoise (LSQ):
ebec, Canada
Lengua de Señas Argentina: Argentina
Lengua de Señas Española: Spain
except Catalo
Lengua Gestual Portuguesa: Portugal
Lingua Italiana dei Segni (LIS): Italy
Lengua de Sinais Brasileira: Brazil
Lugha ya Alama Tanzania (Tanzania
Sign Language): Tanzania
Lughat al-Isharatal-Lubnaniya: Lebanon
Nederlandse Gebarentaal: Netherlands
New Zealand Sign Language (NZSL):
New Zealand
Nihon Shuwa (Japanese Sign
Language): Japan
Norsk Tegnsprak: Norway
Russian Sign Language: Central part of
South Korean Sign Language: South
Svenska Teckenspraket: Sweden
Taiwanese Sign Language (Ziran
Shouyu): Taiwan
Thai Sign Language: Thailand
Türk İşaret Dili: Turkey
Ugandan Sign Language: Uganda
Vlaamse Gebarentaal: Flanders,
i This is not to say that more reflex-like behaviors, like hand preferences, cannot be culturally overwritten. Someone
who is left-handed can be trained to use her/his right hand. This, however, is not an easy task and requires active
instructions and often several years of training (sometimes even using forceful practices such as tying of the
undesired hand). For an overview, see Porac & Lee Berdel Martin (2007).
ii For example, the informal word for mother in Modern Greek is manna, in Latin it is mamma, in French it is
maman, in Turkish it is ana, in Omani Arabic it is mamab, in Chinese it is ma(ma), in Tibetan ama, in Kongo mama,
in Koro ma, in Sitapli ma, in Murrumbigee mamma, just to name a few (cf. Murdock, 1959; Jakobson, 1962; Ingram,
iii Jakobson argues that the first sounds to be produced are usually the labial consonants [m] or [n]. These
consonants are then combined in babbling with the most easily produced vowels, i.e., a schwa or a-like sounds. The
results are syllable sequences similar to mamawhich are unsurprisingly used, or interpreted by adults as being
used, to refer to the most typically important entity in a child’s life, i.e., to the mother.
iv Note that if a sign language has a headshake, it is used as part of a language, that is, its timing is highly
regularized. This means that the on- and offsets of the headshakes are constrained by the language’s grammar
(e.g., Baker-Shenk, 1983; Emmorey, 1999; Wilbur, 2003). This is not true to the same extent for gestures used by
non-signers (which does not mean that gestures and speech are not temporarily coordinated, cf. Wagner, Malisz,
Kopp, 2014). So speech-accompanying headshakes do not have to be obligatorily present simultaneously with
specific words/phrases and they are not so well aligned (e.g., Kendon, 2002).
v Bulgarian Sign Language, for example, seems to be a manual-dominant sign language, i.e., negation is expressed
mainly via manual signs (cf. Bulgarian Ministry of Education and Science, 2017). In some cases, negative meanings,
however, seem to be accompanied by lateral head movements. This is at least suggested by the dictionary
available at (see, for example, the adverb NOTHING or the negative existential verb NOT-EXISTING).
A clearer case is Albanian Sign Language where negative headshakes are, according to my own observations,
vi Note that the alignment of head movements and speech, i.e., the on- and offsets of the gestures, are not
part of the grammatical system as in sign languages. Thus, the sentence would also be well-formed
without head movements or, for example, with the backward head toss before the beginning of the
sentence (see also Harrison 2009; 2014, Andrén 2014).
vii Note that some of the countries shown in Figure 5 were listed as countries in which a negative headshake is used
in Section 3.2.1 (e.g., India). This may simply mean that there are different head gestures for negation (maybe
different types of negation are expressed using different head movements).
viii Interpreting play-soliciting headshakes as being negative (to indicate that the behavior to follow is not to be
taken seriously) is probably too interpretative. It is, however, worth noting that headshakes before game routines
were also observed in human toddlers (Masur, 1980; Kettner & Carpendale, 2013).
ix Previous studies reporting headshakes in African great apes have mainly found that they are used to
solicit play in bonobos, chimpanzees, and gorillas (van Hooff , 1973; Tanner et al., 2006; Pika, 2007, Luef &
Liebal, 2012). This may be very interpretative, but this could be a gesture signaling that the action to
follow after the headshake is not meant to be serious, i.e., that even the play-soliciting headshake involves
some sort of negation. Interestingly, the same behavior was observed in human toddlers: they shake their
heads in game routines before they begin to use it in negative contexts (Masur, 1980; Kettner &
Carpendale, 2013). It is worth noting that headshakes in bonobos may serve different functions, but this
gesture is used more often in preventative contexts than in others (Pinfield, 2013).
... Deictic gestures, too, can be used by bonobos and chimpanzees to direct attention and make requests [162,163,184], as in humans [19,66,67]. The pragmatic functions of head gestures also bear some close resemblance to those of humans, such as bonobos preventing others' actions with head shakes, a presumed potential precursor to human visual signals of negation [185,186]. ...
The view put forward here is that visual bodily signals play a core role in human communication and the coordination of minds. Critically, this role goes far beyond referential and propositional meaning. The human communication system that we consider to be the explanandum in the evolution of language thus is not spoken language. It is, instead, a deeply multimodal, multilayered, multifunctional system that developed—and survived—owing to the extraordinary flexibility and adaptability that it endows us with. Beyond their undisputed iconic power, visual bodily signals (manual and head gestures, facial expressions, gaze, torso movements) fundamentally contribute to key pragmatic processes in modern human communication. This contribution becomes particularly evident with a focus that includes non-iconic manual signals, non-manual signals and signal combinations. Such a focus also needs to consider meaning encoded not just via iconic mappings, since kinematic modulations and interaction-bound meaning are additional properties equipping the body with striking pragmatic capacities. Some of these capacities, or its precursors, may have already been present in the last common ancestor we share with the great apes and may qualify as early versions of the components constituting the hypothesized interaction engine. This article is part of the theme issue ‘Revisiting the human ‘interaction engine’: comparative approaches to social action coordination’.
Le "Cours" de Saussure constitue un ouvrage clé pour quiconque s'intéresse au langage et aux langues ; il est considéré comme fondateur de la linguistique moderne. C'est là que se trouvent exprimés pour la première fois certains des concepts les plus féconds de la linguistique : oppositions binaires (langue/parole, signifiant/signifié, synchronie/diachronie), arbitraire du signe. Ces concepts seront largement affinés ou contestés, et nourriront la réflexion de générations de linguistes. Avec la reproduction de l'édition originale de 1916 établie par les élèves de Saussure d'après leurs notes, le lecteur trouvera un appareil critique complet dû à Tullio de Mauro, dont une biographie de Saussure et des notes. Les commentaires sont particulièrement instructifs, car ils font apparaître les violentes critiques qui ont suivi la publication du "Cours", ainsi que l'influence considérable qu'il a exercée et continue d'exercer. Ce livre peut être lu sans connaissances préalables en linguistique. "–Guillaume Segerer"
This paper is part of a study examining how negation is marked in Greek Sign Language (GSL). Head movements which are reported to mark negation in other sign languages have been examined to see if they are also used in GSL along with negation sings and signs with incorporated negation. Of particular interest is the analysis of the backward tilt of the head which is distinct for marking negation in GSL.
Sign languages are natural languages, they are not consciously invented by anyone, but rather develop spontaneously wherever deaf people have an opportunity to congregate and communicate regularly with each other. This chapter briefly explains how they do so. It examines the structure of the sentence (syntax), and then moves to the structure of the smaller units of language, those that may be compared to the meaningless but identifiable sounds of speech (phonology). The chapter ends the linguistic description with a discussion of the structure of words (morphology). There is something about human cognition that converges on a complex and rich language system with particular formal and even neurological characteristics, even when the evolutionarily dominant channel for its transmission is not available. Sign language study has also strengthened the claim that the acquisition of language by children is a natural and automatic process with a set timetable, pointing to some degree of genetic predisposition.