Here is a simple script that you can use to navigate a document from segment to segment using Alt+Left and Alt+Right.
// Move to next segment
!right::
Send, {ctrl down}{pgdn}{ctrl up}
Send, {down}
Send, {ctrl down}{pgup}{ctrl up}
Return
// Move to previous segment
!left::
Send, {ctrl down}{pgup}{ctrl up}
Send, {up}
Send, {ctrl down}{pgup}{ctrl up}
Return