FoundationalConceptsNeuroscience

spores (Fig. 11.2). The tip can elongate at a rate of several millime-
ters per hour and will grow in the direction of light (phototropism).
Although the mycelium of the fungus may be growing deep within a
substrate material, the light sensitivity of its sporangiophores enables
the fungus to disperse its spores into open terrain.
Thus, many organisms—it is probably safe to say all organisms—
detect and respond to stimuli from the environment. They possess
sensation. What about the mental experience of perception? Do E.
coli and Phycomyces have mental experiences? It is generally assumed
that mentality is limited to organisms with complex nervous systems.
But this is an assumption—and really, who knows? Is it possible that
microorganisms have an experience of what it is like to be them? All
we are sure of at this point, if we are sure of anything, is that we can
only really know about mental experiences in ourselves and in other
humans with whom we can communicate using language. More dis-
cussion of this fascinating issue later.