Relegation-threatened Livorno have sacked Domenico Di Carlo after just 88 days in charge and re-appointed Davide Nicola.
Virgil van Dijk claims he knows nothing of interest from English clubs and is keen to prove himself in the Champions League with Celtic.
The 23-year old previously spent two years at Falkirk, leaving a year ago, but has struggled to pin down a regular place at the npower Championship side and was loaned out to Barnsley and then Carlisle.
Higgingbotham, whose deal is subject to what Motherwell called "registration formalities", will add creativity to Stuart McCall's attacking options following the sale of Jamie Murphy to Sheffield United.
Higginbotham told MFCTV: "I am really pleased and excited to be here and I want to thank the gaffer and all the players for making me feel so welcome."