Lesson 25 (Limbic system)

Other than the amygdala, what are the three areas the hypothalamus projects to?:

Autonomic centers, the pituitary glands, and the anterior part of the thalamus

Where does the nucleus acumbens terminate?

Axons of neurons in the nucleus accumbens terminate within the basal ganglia. This pattern indicates that the nucleus accumbens is a link between the limbic system and the basal ganglia.

What is the function of the cingulate cortex?

Cingulate cortex helps mediate the emotional response to pain and to more abstract stimuli

Input to the hypothalamus from the hippocampus arrives via:

Fornix

The main two functions of the hypothalamus are:

Homeostasis and preparing the body for emotional responses

Input to the hypothalamus from the septal nuclei arrives via:

Medial forebrain bundle

The amygdala projects to:

The amygdala projects to orbital, cingulate, temporal, and entorhinal cortex. These connections are exceptions to the general rule that cortex receives its input solely from the thalamus. It also projects to subcortical structures, the hypothalamus (both directly and via the stria terminalis), the hippocampus, the septal nuclei and the thalamus.

Where does output from the septal nuclei go?

The axons of neurons in the septal nuclei travel via the fornix back to the hippocampus, via the stria terminalis to the hypothalamus, and via the medial forebrain bundle to the amygdala.

What is the function of the hippocampus?

The hippocampus mediates the formation of new declarative memories.

What is the function of the nucleus accumbens?

The nucleus accumbens plays an important role in modulating motivation and reinforcement. It is the site of action for many addictive drugs such as cocaine and amphetamines via increased dopamine in the N.A.

What is the function of the septal nuclei?

The septal nuclei are related to the experience of pleasure

Where do the septal nuclei receive their input from?

The septal nuclei receive a large input from the hippocampus and a smaller projection from the amygdala and the medial part of the midbrain (mesencephalic) reticular formation

Output from the hypothalamus to the amygdala, the hippocampus and the septal nuclei travel via which tracts:

The stria terminalist; Fornix; medial forebrain bundle

Cingulate cortex receives input from:

VP thalamus (remember, the one that relays somatosensory information to the cerebral cortex) carrying pain information, and from the anterior thalamus.

The hippocampus projects to the:

anterior thalamus which, in turn projects to prefrontal, orbital, and cingulate cortex. It also projects to the amygdala and the hypothalamus (via the fornix).

The hypothalamus effects homeostasis via these three thing:

autonomic nervous system, pituitary gland, and changing motivation

The biggest input to the hippocampus is from the:

entorhinal cortex

Cingulate cortex projects to:

entorhinal cortex and amygdala

Where does the nucleus acumbens receive input from?

the amygdala

Stimulation of the amygdala can elicit:

the same drive-related behaviors elicited by stimulating the hypothalamus directly, e.g., eating and drinking or stopping eating and drinking, but these effect is more natural in that they have slower onset and offset.

Input to the hypothalamus arrives from the amygdala via:

the stria terminalis

The amygdala receives input from:

orbital, cingulate, entorhinal, and temporal cortex. It also receives input from subcortical structures, the hypothalamus, hippocampus, brainstem, septal nuclei, and thalamus. Connections - Output - The amygdala projects to