j *@ - Sociedade Brasileira de Psicologia

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SOG. So far, the behaviour o'f single cells 1M been exnmined in response to different
stimuli delivered to the antennae and mouthp' m s or to intracelular stimulation. After
th e recor din gthe
neurons have been. stained with the Iluorescen' t dye Lucifer Yellow
for morpholoscal analysis. . ,
However, due to technical and preparational difficulties electrophysiology in
honey bees is still in an early phase. Only recently has it been possible to overcome
some of the problems leading to intracelbxlnr recordings of longer duration and better
quality. Most of the neurons show a spontaneous spike activity, which can be the
norm al physiological state or which can be induced by the impalement of the cell.
Reactions of neurons to a Sven stimulus are usualy recognized as an excitation
(increase of sfontaneous frequency or generation of action potentials or excitatory
synaptic potentizs' in not spontaneously active cels) or an inhibition (decrease of
spontaneous frequency or inhibitory synaptic potentials). Many of the recorded
neurons are multimodal, which means they react to several sensory stimuli. Somethnes
different readions to tle snme stimulus cnn be observed. In some cases, a stimulus
paradigm , similar to that in behavioural experiments was used to study the effects of
sensitization on the level of single cells. Neurons, which changed their response
behaviour due 'to the sensitizing stim ulus could be identified in al three neuzopil
areas, from which recordings were made. The effects seem to be more drastic in the
sensory and motor regions, while only smal changes were recorded ilz the mushroom
bodies. This would support the notion that the mushroom bodies may not be involved
in the processing of non-associative components of odor conditioning.
A good quality recording is required for the interpretation of the reactions as
a real physiological behaviour. As mentioned above, the qllRlity of recordings could be
im proved, so that in case of a good recording not only spike frequencies can be interpreted,
but also synaptic potentials and clianges in membrane properties such as tze
Zput resistance. '
Conclusions
lmmunohistochemical and eledrophysiological investigations are important
methods with which to analyse the functional properties of the bee brain. Immunohistochemimtry
offers the possibilities (1) to resolve anatomicaly so far unknown or
uncleu structures, (2) to analyse functional iversities between anatomicaly homogenous
neurori m pulations and (3) to mnk'e ftrst functional assumptions about diferent
brain areas by studying the distribution of various neuroadive substances.
Neurophysiolo' gy could provide some knowledge about (1) the behaviour of single cels
and their physiological properties in correhtion with different stimullzs modalities,
intracelllnr stimulation and plastic changes during sensitization, habituation and
conditioning, (2) about tle reaction of single cels in re'sponse to pharmaca injected