Basal ganglia
striatum (neostriatum)
ncl. caudatus
putamen
ncl. accumbens
dorzal striatum
ventral striatum
globus pallidus
(pallidum, paleostriatum) med. (internal) seg.
lat. (external) seg.
dorsal pallidum
ventral pallidum
substantia nigra
ncl. subthalamicus
ventralis tegmental area (VTA)
pars compacta
pars reticularis
BASAL GANGLIAAND RELATED STRUCTURES
VENTRAL PALIDUM AND
VENTRAL STRIATUM
AFFERENTATION OF BG
Dopamin-D1 = facilitatory on neurons of direct striatopalidal path
Dopamin-D2 = inhibitory on neurons of indirect striatopalidal path
SNPC → striatum - dopamin
AFFERENTATION OF BG
Input nuclei - STRIATUM
• from cortex - corticostriatic tr. – somatotopic arrangement
• from thalamus - centromedial ncl. – somatotopic arrangement
• from substantia nigra pars compacta - nigrostriatal tract
dopaminergic projection, final effect according to D1 or D2 receptors
AFFERENTATION OF BG
glutamate or aspartate (excitation)
INTRINSIC CONNECTION OF BG
direct (-) GABA
indirect (-) GABA, (+) glutamate
• direct striatopallidal connections mainly into GPpm/SNpr (-GABA)
• SNpc into striatum - dopamine
• indirect striatopallidal connections into GPpl (- GABA) nclSth
 GPpm/SNpr (+glu), do GPpl (-)
INTRINSIC CONNECTION OF BG
EFFERENT CONNECTIONS OF BG
Output nuclei - GPpm, SNpr and ventral pallidum
• inhibitory connection (GABAergic) with motor thalamus (VL a VA)
EFFERENT CONNECTIONS OF BG
CORTEX
striatum
pallidum
thalamus
SMA
+
- -
+
GENERAL CONNECTIONS OF BG
cortex
striatum
pallidum
thalamus
cortex
+
- -
+
subthalamus
- +
SNPC
D1
+
D2
GENERAL
CONNECTIONS OF BG
FUNCTIONAL LOOPS OF BASAL GANGLIA
Illustration of BG involvement in motor regulation
ASSOCIATION (PREFRONTAL) LOOP
LIMBIC LOOP
OCULOMOTOR LOOP
SENSORY-MOTOR LOOP