Take note of the following sentence:

Paul Newman himself thought little of them. [1]

In this sentence, is "little" modifying the verb " thought" as an adverb or there's something implicit between "little of"? I could not understand.

Thank you

Take note of the following sentence:

Paul Newman himself thought little of them. [1]

In this sentence, is "little" modifying the verb " thought" as an adverb or there's something implicit between "little _____ of"? I could not understand.

Thank you