Anxiety disorders are the most prevalent central nervous system diseases imposing a high social burden to our society. Emotional processing is particularly controlled by GABA-ergic transmission in the amygdala. Using in situ hybridization and immunohistochemistry we now investigated changes in the expression of GABA synthesizing enzymes (GAD65 and GAD67), GABA(A) (α1-5, β1-3, γ1-2) and GABA(B) ...

Slow oscillations (<1 Hz) in neural activity occur during sleep and quiet wakefulness in both animals and humans. Single-cell recordings in cortical neurons have shown that these oscillations are driven by a combination of excitatory and inhibitory synaptic inputs. During up-states, although the ratio between them varies between cells, excitation and inhibition follow similar time courses. Neur...

In the lateral amygdala (LA), training-induced increases in neuronal responsiveness to conditioned stimuli (CSs) reflect potentiated sensory responses that drive conditioned behaviours (CRs) via LA's targets. The basolateral nucleus of the amygdala (BL) receives LA inputs and projects to various subcortical sites that can drive aversive and appetitive CRs. Consistent with this, BL neurons also ...

Rats with lesions in the basolateral amygdala chose different foods from control rats in 10-min. food-preference tests. The normal rats ate primarily familiar chow, while the amygdala-lesioned rats ate primarily novel foods. The lesioned rats did not select indiscriminately but showed definite preferences. With repeated testing, the normal rats' preferences became similar to those of the amygda...

The nucleus accumbens (NAc) has been implicated in a variety of associative processes that are dependent on the integrity of the amygdala and hippocampus (HPC). However, the extent to which the two subregions of the NAc, the core and shell, form differentiated circuits within the amygdala- and hippocampal-ventral striatal circuitry remains unclear. The present study investigated the effects of ...

Do learning and retrieval of a memory activate the same neurons? Does the number of reactivated neurons correlate with memory strength? We developed a transgenic mouse that enables the long-lasting genetic tagging of c-fos-active neurons. We found neurons in the basolateral amygdala that are activated during Pavlovian fear conditioning and are reactivated during memory retrieval. The number of ...

Vocalizations emitted within a social context can trigger call-specific changes in the emotional and physiological/autonomic state of the receiver. The amygdala is implicated in mediating these changes, but its role in call perception remains relatively unexplored. We examined call and pitch selectivity of single neurons within the basolateral amygdala (BLA) by recording spiking activity in res...

Acknowledgements: This study was supported by a VA Merit Review (SDM) and the VISN 6 MIRECC. We thank Drs. Robinson for technical help with confocal imaging.

Should the medial temporal lobe (MTL) of primates--which includes allocortical structures such as the hippocampus, neocortical structures such as the parahippocampal cortex, and nuclear structures such as the basolateral amygdala--be considered a single "thing"? According to the prevailing view, here termed the reification theory, the answer is yes. According to this theory, the MTL functions a...