| | Dear Martin,
Both good questions.
1) Visualizations: I have tended to use kasina objects: dots of primary colors both of paper and on computer screen (take a dot character and make it of some huge font and you get a kasina disk that glows nicely), candle flames, pentagrams, tarot cards, and other objects. I have found these material supports of value initially until I can get the learning sign and counter sign. I find that when off retreat my visualization skills drop off dramatically, but I don't practice them every day. When 5-10 days into a retreat, I can really visualize well, with the mind made malleable through strong concentration, things do what I wish with little effort and will often surprise me how much detail will arise without my even asking for it. Thus, very strong concentration and lots of hours pays off, in my experience. I stick to the colors and shapes themselves like glue to the exclusion of nearly everything else as much as possible. After all, this is concentration practice. I haven't found these exercises causing much agitation, particularly candle flame and kasinas.
2) Anxiety and laxity are made of sensations, and so they are good objects for vipassana like everything else. Notice the individual sensations that make them up rather than caring about exactly which is which, as it is more complex than that.
Helpful?
Daniel |