1. There are two main theories of selective attention: the selective filter theory and the attenuation theory. The selective filter theory proposes that only relevant information gets through to consciousness, while the attenuation theory says irrelevant information is weakened but can still get through. 2. Attentional resource theory posits that attention is a limited cognitive resource, and performing multiple complex tasks at once reduces available resources and leads to poorer performance and more mistakes. 3. Factors that influence attention include anxiety, arousal, task difficulty, and skills - being anxious, tired, or inexperienced with a task reduces attention while excitement or practice can enhance it.