Cognition ::Fear and Aggression

Question 1

Auditory Fear Conditioning: Pathways

Answer 1

There are two main central pathways underlying auditory fear conditioning: The direct pathway and the indirect pathway. Before describing these pathways which are specific to auditory fear conditioning, it is important to demonstrate both the auditory pathway and the somatosensory pathway separately before showing their convergence in the amygdala.
In auditory fear conditioning, the organism must be able to detect sound thus the auditory pathway and its central components play a significant part in this type of conditioning.

Question 2

Somatosensory Pathway

Answer 2

Since the neutral stimulus and the unconditioned stimulus are given simultaneously, both pathways are activated at the same time. This means that in the case of the rat above, the electric shock results in the activation of the pain pathway.

The electric shock is administered to the rat which is detected by nocireceptors, this sensory data is then transduced and carried by sensory neurons of the spinothalamic tract. It is carried to prominent nuclei of the somatosensory thalamus such as the ventral posterolateral thalamic nucleus and the intralaminar thalamic nucleus. It then travels onto the somatosensory cortex.

Question 3

Auditory Fear Conditioning: Pathways

direct pathway and the indirect pathway.

Answer 3

The direct pathway is the thalamic - amygdaloid pathway and the indirect pathway is the thalamic-cortical- amygdaloid pathway.

The thalamo-amygdala route, only passes through the thalamus and arrives quickly at the central nucleus of the amygdala with sensory information, and the thalamo-cortico-amygdala pathway, which passes through the thalamus, sensory cortex and hippocampus, takes longer to arrive at the lateral and basal nuclei of the amygdala with contextual information which informs the amygdala whether the stimulus is a real danger.