76 • CHAPTER 3 Perception
respond to sounds that are associated with actions. These neurons, also in the
premotor cortex, called audiovisual mirror neurons, respond when a monkey
performs a hand action and when it hears the sound associated with this action
(Kohler et al., 2002). For example, the results in ● Figure 3.41 show the response
of a neuron that fi res (a) when the monkey sees and hears the experimenter break
a peanut, (b) when the monkey just sees the experimenter break the peanut, (c)
when the monkey just hears the sound of the breaking peanut, and (d) when the
monkey breaks the peanut. What this means is that just hearing a peanut breaking
or just seeing a peanut being broken causes activity that is also associated with the
perceiver’s action of breaking a peanut. These neurons are, therefore, responding
to the characteristics of observed actions—in this case, what the action of breaking
a peanut looks like and what it sounds like.
Since the fi rst descriptions of mirror neurons in the 1990s, a great deal of
research has confi rmed the existence of these neurons in both monkeys and
humans. Researchers have proposed other functions in addition to understanding
another person’s actions, including understanding language (Rizzolatti & Arbib,
1998), imitation (Iacoboni, 2009), defi cits in autism (Dapretto et al., 2006), and
determining another person’s intentions (Iacoboni et al., 2005). Not all researchers
agree with all of the functions that have been attributed to mirror neurons, but
there is no question that mirror neurons provide an impressive example of the linkATTENTION AND VISUAL PERCEPTION
Although we have described many different principles and experiments in this
chapter, we can summarize the chapter by noting that perception is the outcome
of processes that are also involved in other cognitive functions. In common with
memory, problem solving, and decision making, perception involves underlying
“intelligent” processes such as inference, taking into account multiple factors,
and making use of prior knowledge. Like memory, it is sometimes fallible, but
often correct and highly adaptive. But sharing properties with other cognitive pro-
cesses is only part of the story. The other part is that perception and all cognitive
processes interact with each other. This interaction will be apparent in the next
chapter, when we see that what we perceive is often determined by how we pay
attention, and how we pay attention is infl uenced by perceptual qualities of the
environment.● FIGURE 3.41 Response of an
audiovisual mirror neuron to four
diff erent stimuli. (Source: Kohler et al., 2002.)100Sees experimenter
break peanut0
(b)100Hears sound0(c)100Monkey breaks peanut0(d)100Firing rateSees experimenter break
peanut and hears sound0Firing rateFiring rateFiring rate(a)- What is experience-dependent plasticity? Describe the kitten-in-the tube
experiment and the Greeble experiment. What is behind the idea that neurons
can refl ect knowledge about properties of the environment? - Describe the link between perception and action in everyday perception, by
giving a specifi c example and describing the interaction between perceiving and
taking action. - Describe the Ungerleider and Mishkin experiment. How did they use the
procedure of brain ablation to demonstrate what and where streams in the
cortex? - Describe the dissociation procedure used in neuropsychology and how it was
used to determine the presence of two processing streams in patient D.F. How
do the results obtained from D.F. compare to the results of the Ungerleider and
Mishkin monkey experiment? - Describe how the perception and action pathways both play a role in an action
such as walking on a crowded sidewalk. - What is a mirror neuron? What are some potential functions of mirror
neurons?
TEST YOURSELF 3.3
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