Share
Explore BrainMass

Neuroanatomical Structure & Function, Synapses and Addiction

These are discussion board questions that only require brief answers.

Please help me write responses for:

NEUROANATOMICAL STRUCTURE
Based on the text, describe the functioning of one neuroanatomical structure, its relation to other structures, and the types of cognitive/behavioral deficits that might be observed with damage to this area. (I chose the Olfactory Bulb)

SYNAPSES
For this questions, please describe the synapse of a terminal button onto a dendritic membrane. Indicate at least six ways that a drug can affect synaptic transmission. Compare the changes in drug reactivity that is noted in tolerance and sensitization. Provide an explanation for each effect.

ADDICTION
Based on your text, summarize the major effects of the opiates, and link these effects to the various receptors that have been identified in the brain. Distinguish between physical and psychological addiction.
Please note references

Attachments

Solution Preview

1. NEUROANATOMICAL STRUCTURE:

The axons of the olfactory neurons connect to the brain through tiny, sieve like holes of a bony structure known as the cribiform plate. The axons of each nostril bundle to form the olfactory nerve, which is responsible to transmit impulses to the olfactory bulbs. Olfactory bulbs are two in number namely; the right and left olfactory bulbs. Olfaction is "ipsilateral" in nature, in the sense that the right olfactory bulb receives information from the right nostril while the left olfactory bulb receives information from the left nostril. Information does not get crossed over from right to the left nostril. Sensory information moves to the primary olfactory cortex from the olfactory bulbs to the piriform cortex which in turn is connected to the limbic system. Here, the brain structures for expression of emotions are present. The chief limbic structures associated with the olfactory system are the amygdale, hippocampus, and hypothalamus. The olfactory bulb is separated by two synapses from the amygdala, which is meant for expressing and experiencing emotions. Three synapses are necessary to connect to the hippocampus that is involved in associative memory. There exists a direct connection between the olfactory area, amygdala, and hippocampus as compared to those between these brain areas and any other sense. Thus, this unique neuroanatomical link between olfaction and other parts of the brain related to emotion and memory plays a vital role to understand why the memories evoked by odor are different from other types of memories regarding their emotional potency. It also answers queries related to the existence of relationship between odors and emotions. The olfactory information moves from the limbic system to the orbitofrontal cortex from where the same is directed to a higher level in the neocortex for the purpose of cognitive processing. The orbitofrontal cortex also receives information related to taste and interprets flavor. The process of molecular composition of an odorant being translated into the psychological perception still remains a mystery. The most widely accepted hypothesis suggests that the process involves pattern-activation. It depends upon how well an odor molecule fits into the olfactory receptor. Once, the receptor is stimulated, it gives rise to an action potential / nerve impulse in the neurons of the olfactory bulb. Thus, the pattern of nerve impulse in the olfactory bulb determines the smell that is perceived. But, the pattern-activation hypothesis has not yet been proved through genuine research. The sense of smell and the related emotions varies from one individual to the other.

Cognitive/behavioral deficits ...

Solution Summary

The assignment deals with the neuroanatomical structure, function of Olfactory Bulb, and the types of cognitive/behavioral deficits that might be observed with damage to the same. Description of synapse of a terminal button onto a dentritic membrane, six ways as to how a drug affects synaptic transmission. Comparison of the changes in drug reactivity noted in tolerance and sensitization. Summarization of the major effects of opiates in relation to its effects on various receptors identified in the brain. Differentiation between physical and psychological addiction.

$2.19