Listing and adjusting mouse and touchpad devices

Listing devices

xinput list

List device properties

xinput list-props 8 

(8 = device ID, from xinput list)

Adjusting scrolling sensitivity for Synaptics touchpad

xinput --set-prop "SynPS/2 Synaptics TouchPad" "Synaptics Scrolling Distance" 250 250

(Default values are 100 100, which you can get from xinput list-props)

Adjusting mouse sensitivity for Synaptics touchpad

xinput --set-prop "SynPS/2 Synaptics TouchPad" "Device Accel Constant Deceleration" 1.4
xinput --set-prop "SynPS/2 Synaptics TouchPad" "Device Accel Velocity Scaling" 1