Attention spans and deficits

ירושלמי ברכות פרק ב סוף הל' ד

א"ר חייא רובא אנא מן יומי לא כוונית אלא חד זמן בעי מכוונה והרהרית בלבי ואמרית מאן עליל קומי מלכא קדמי ארקבסה אי ריש גלותא.   

שמואל אמר אנא מנית אפרוחיא   

רבי בון בר חייא אמר אנא מנית דימוסיא   

א"ר מתניה אנא מחזק טיבו לראשי דכד הוה מטי מודים הוא כרע מגרמיה 

 Yerushalmi Berachot 2:4

Ribbi Hiya said, "I never got a chance to remain attentive during my prayers. One time, I really tried to focus. Instead, however, all I could do is wonder who walks into the king's office first when they go to visit him: the prime minister or the head of the Jewish community (Resh Galuta)."

Shemuel said, "I would absentmindedly count the birds fluttering around during my tefila."

Ribbi Bon bar Hiya said, "I would absentmindedly count the rows of brick in the nearest wall."

Ribbi Matnia said, "I am ever so grateful to my head, for when I reach Modim in my tefila, it bows on my behalf."

A"A would emphasize from here that maintaining focus during tefila is not an easy task at all. It is something that even the amoraim would struggle with at times. However, according to Halacha, it is absolutely necessary to at the very least say the first beracha of amida with proper attention and focus.
May HB"H grant us the ability to remain attentive for all our tefilot in the merit of the limmud Torah we just accomplished by learning this Yerushalmi.