Sound in Electronic Gambling Machines - Game Sound Technology and Player Interaction: Concepts and Developments - page 13

1997). Wolfson and Case (2000) studied heart rate
response to manipulation of loudness of sound in
a computer game, finding that louder sounds led
to increased heart rate, and discussed the impact
that physiological arousal has on our attention
levels. They note:

though they tested their student subjects during an
examination. Rohner and Miller (1980) found that
music had no influence on anxiety levels. Pitzen
and Rauscher (1998) and Hirokawa (2004), on the
other hand, more recently found that stimulating
music increased energy and relaxation (increasing
GSR but not heart rate).
Although there are many studies about music
in isolation and its physiological effect on listen-
ers, there has been much less research on music's
impact on GSR while taking into consideration
the interaction between sound and visual image
(for example, Thayer & Levenson, 1983). Percep-
tual studies (non-physiologically based research)
from the field of advertising suggest that image
and sound, when used congruently (that is, for
instance, when both have a similar message),
tend to amplify each other (for instance, Bolivar,
Cohen, & Fentress, 1994; Bullerjahn & Gülden-
ring, 1994; Iwamiya, 1994). There have also been
studies into the physiological effects of gambling,
which have shown that pupils may dilate, heart
rate may increase, and skin conductance levels
increase (raising the GSR). Collectively, these are
known as arousal levels, and it is the arousal induc-
ing properties of slot machines that are affected
by winning and losing, with increased arousal
levels for wins (such as Coventry & Constable,
1999; Coventry & Hudson, 2001; Sharpe, 2004).
Additionally, a number of studies, for instance,
research by Dickerson and Adcock (1987), have
questioned whether there is a connection between
physiological responses to gambling and wider
psychological issues governing perceptions of
such elements as gambling environment, luck,
and mood. These studies suggest there is some
evidence to support both psychological and
physiological responses to gambling behaviors
are fuelled in part by a player's illusion of control
(for example, Alloy, Abraham, & Viscusi, 1981).
In more recent research into computer games
and the computer gaming environment, Hébert,
Béland, & Dionne-Fournelle (2005) have dis-
covered that, “for the first time…auditory input

People performing a task when minimally aroused
are more likely to be slow, indifferent, and spread
their attention across a wide range of stimuli.
When highly aroused, people tend to be faster
but less accurate, and they focus mainly on the
most salient aspects of a task. Thus both high and
low levels of arousal can have detrimental effects
on performance. (Wolfson & Case, 2000, p. 185)

Physiological responses to stimuli can be tested
using a variety of measures, including (but not
limited to) electroencephalograms (EEGs), facial
electromyography, heart rate, pupil dilation and
electrodermal response. Galvanic skin response
(GSR), one component of electrodermal response,
also known as skin conductance response or sweat
response, is an affordable and efficient measure-
ment of simple changes in arousal levels—one
of the reasons why it is the main component of a
polygraph device. Essentially, GSR measures the
electrical conductivity of the skin, which changes
in resistance due to psychological states. (See
Nacke & Grimshaw, 2011 for the use of such
measures when assessing psychophysiological
responses to computer game sound.)
Studies using GSR on subjects while being
exposed to music date back to at least the 1940s
(for example, Dreher, 1947; Traxel & Wrede, 1959)
but are highly contradictory due to the conditions
in which the studies took place. Sound and music
has a known influence on listener's arousal and
anxiety levels, but this depends on many factors
including the degree of musical knowledge, the
tempo of the music, the familiarity with the music,
preference for the music, and recent exposure to
that music. Smith and Morris (1976) found that
stimulating music increased worry and anxiety, al-