GIST: Improving Parameter Efficient Fine Tuning via Knowledge
  Interaction
Jiacheng Ruan Jingsheng Gao Mingye Xie Suncheng Xiang Zefang Yu Ting Liu Yuzhuo Fu
The Parameter-Efficient Fine-Tuning (PEFT) method, which adjusts or
introduces fewer trainable parameters to calibrate pre-trained models on
downstream tasks, has become a recent research interest. However, existing PEFT
methods within the traditional fine-tiuning framework have two main
shortcomings: 1) They overlook the explicit association between trainable
parameters and downstream task knowledge. 2) They neglect the interaction
between the intrinsic task-agnostic knowledge of pre-trained models and the
task-specific knowledge in downstream tasks. To address this gap, we propose a
novel fine-tuning framework, named GIST, in a plug-and-play manner.
Specifically, our framework first introduces a trainable token, called the Gist
token, when applying PEFT methods on downstream tasks. This token serves as an
aggregator of the task-specific knowledge learned by the PEFT methods and forms
an explicit association with downstream knowledge. Furthermore, to facilitate
explicit interaction between task-agnostic and task-specific knowledge, we
introduce the concept of Knowledge Interaction via a Bidirectional
Kullback-Leibler Divergence objective. As a result, PEFT methods within our
framework can make the pre-trained model understand downstream tasks more
comprehensively by leveraging the knowledge interaction. Extensive experiments
demonstrate the universality and scalability of our framework. Notably, on the
VTAB-1K benchmark, we employ the Adapter (a prevalent PEFT method) within our
GIST framework and achieve a performance boost of 2.25%, with an increase of
only 0.8K parameters. The Code will be released.