Table 1.

Development of sex differences in medium spiny neuron electrophysiological properties varies by striatal region.

Electrophysiological Property	Developmental Stage	Caudate-Putamen	Nucleus Accumbens Core	Nucleus Accumbens Shell
Intrinsic Cellular Excitability	Pre-puberty	♀ > ♂	♀ = ♂	♀ = ♂
	Adult	?%	?	?
Excitatory Synaptic Input	Pre-puberty	♀ = ♂	♀ > ♂	♀ = ♂
	Adult	?%	♀ > ♂*	♀ = ♂*,#

Notes: Sex differences in medium spiny neuron electrophysiological properties vary by striatal region. Medium spiny neurons show increased intrinsic excitability in female compared to male caudate-putamen, but no sex differences in excitatory synapse properties. In contrast, medium spiny neurons in the nucleus accumbens core show increased excitatory synapse number in females compared to males. This is indicated by both neuroanatomical studies and in electrophysiological measures such as the frequency of miniature excitatory postsynaptic currents.

^%Increased excitability of adult female compared to male caudate-putamen neuron excitability has been detected in vivo, but it is unknown if this is due to alterations in intrinsic cellular excitability and/or excitatory synaptic input.

^*Gonad-intact animals, females not sorted by estrous cycle stage.

^#Most but not all nucleus accumbens shell literature shows no evidence of sex differences in excitatory synaptic input in control animals.