Dual-to-Dual MLLMs refer to Multimodal Large Language Models, which can enable unified multimodal comprehension and generation through text and image modalities. Although exhibiting strong instantaneous learning and generalization capabilities, Dual-to-Dual MLLMs still remain deficient in lifelong evolution, significantly affecting continual adaptation to dynamic real-world scenarios. One of the challenges is that learning new tasks inevitably destroys the learned knowledge. Beyond traditional catastrophic forgetting, Dual-to-Dual MLLMs face other challenges, including hallucination, instruction unfollowing, and failures in cross-modal knowledge transfer. However, no standardized continual learning framework for Dual-to-Dual MLLMs has been established yet, leaving these challenges unexplored. Thus, in this paper, we establish Continual-NExT, a continual learning framework for Dual-to-Dual MLLMs with deliberately-architected evaluation metrics. To improve the continual learning capability of Dual-to-Dual MLLMs, we propose an efficient MAGE (Mixture and Aggregation of General LoRA and Expert LoRA) method to further facilitate knowledge transfer across modalities and mitigate forgetting. Extensive experiments demonstrate that MAGE outperforms other continual learning methods and achieves state-of-the-art performance.
Figures & tables
Figure 1: Continual-NExT: A framework for lifelong multimodal learning in Dual-to-Dual MLLMs. The left part shows its multimodal generation capability. The middle part illustrates its development across diverse training stages. The right part presents its supported downstream tasks.
Figure 2: Overview of Continual-NExT, including tasks, task types, sizes, and examples.
Figure 3: Parameter update patterns across heterogeneous tasks from global output view (left) to local input view (right). VQAv2->ImageNet refers to first training on VQAv2 (Task 1) and then training on ImageNet (Task 2). Pixel value represents the absolute discrepancy between the parameters learned from Task 1 and Task 2.
Figure 4: Results of different LoRA settings.
Figure 5: Overview of the MAGE. We insert four types of LoRA into the MLLM, Image/Text General LoRA (G-LoRA) and Image/Text Expert LoRA (E-LoRA). Then, we use the parameter-wise EMA strategy to update LoRA corresponding to the specific input and output modality of current task, while freezing that unrelated to it.
Method
Venue
Accuracy on Each Task
Overall Results
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
Avg.ACC( ↑ )
Forgetting( ↓ )
New.ACC( ↑ )
Zero-Shot
-
26.64
28.38
19.76
13.78
25.54
58.76
28.81
-
-
LoRA ( Hu et al., 2022 )
ICLR’22
59.68
65.19
31.18
41.22
66.60
91.27
42.23
20.36
59.19
18.40
61.01
30.60
19.38
32.70
91.27
MoELoRA ( Chen et al., 2024 )
NIPS’24
62.10
82.16
31.46
21.52
70.00
91.54
43.90
19.08
59.80
25.32
63.57
30.59
16.04
36.32
91.54
Table 1: Avg.ACC, Forgetting, and New.ACC performance comparisons. Accuracy on each task refers to the performance after training on the current(first row)/final(second row) task. Bold fonts represent the best performance, and underlined fonts represent the second-best performance. Upper-Bound denotes once training all the datasets.
Figure 6: Visualized examples for each method after UCL on the Continual-NExT framework.
Method
Forgetting Type Metrics
Avg.IUF( ↓ )
Avg.HAL( ↓ )
Avg.OTH( ↓ )
LoRA
9.07
11.11
0.18
MoELoRA
8.47
10.53
0.08
MAGE
4.42
7.48
0.36
Table 2: Comparisons on Avg.IUF, Avg.HAL and Avg.OTH between LoRA, MoELoRA, and MAGE.
Method
LoRA
MAGE
Tra.Task
Flickr30k
OCRVQA
Flickr30k
OCRVQA
Flickr30k
OCRVQA
Flickr30k
OCRVQA
Evl.Task
VQAv2
VQAv2
Flickr30k
Flickr30k
VQAv2
VQAv2
Flickr30k
Flickr30k
Trans.Type
Text → Text
Text → Image
Text → Text
Text → Image
Accuracy
20.10
50.26
31.18
31.26
43.56
57.29
31.26
32.02
Table 3: Knowledge transfer comparisons between LoRA and MAGE in Continual-NExT.
Method
Accuracy on Each Task
Overall Results
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
Avg.ACC( ↑ )
Forgetting( ↓ )
New.ACC( ↑ )
MoE
25.32
63.57
30.59
16.04
36.32
91.54
43.90
19.08
59.80
EW
47.28
60.93
31.25
18.46
31.30
91.29
46.75
15.66
59.81
EW+GA
48.54
60.59
30.97
20.76
33.92
91.25
47.67
14.90
60.09
MAGE
45.42
68.02
31.44
27.28
34.10
91.19
49.58
12.26
59.79
Table 4: Ablation study on different method components and their influence on each task’s performance. The best and second-best results are marked in bold and underlined , respectively.
Method
Modality
Overall Results
Text
Image
Avg.ACC( ↑ )
Forgetting( ↓ )
New.ACC( ↑ )
Default
43.71
61.32
49.58
12.26
59.79
Reverse
46.07
56.45
49.53
12.17
59.67
Alphabet
45.18
57.31
49.22
12.35
59.51
Table 5: UCL performance under different task orders.
Figure 7: Training and evaluation case visualization in Continual-NExT.
Figure 8: Comparison radar chart of Accuracy on each task between PEMA and DEMA.
Figure 9: Results of distinct methods on each task.
Figure 10: Prompt used for text generation consistency evaluation.
Figure 11: Prompt used for image generation consistency evaluation.
Figure 12: Prompt used for image editing consistency evaluation.
Metrics
LoRA
MoELoRA
EWC
LAE
PGP
CIA
RegLoRA
Ours(MAGE)
Upper-Bound
Avg.ACC
42.23 ± 0.83
43.90 ± 0.47
47.00 ± 0.85
45.25 ± 0.61
47.70 ± 0.52
47.99 ± 0.18
47.39 ± 0.67
49.58 ± 0.58
53.31 ± 0.49
Forgetting
20.36 ± 0.31
19.08 ± 0.22
15.85 ± 0.19
16.29 ± 0.28
13.54 ± 0.37
14.89 ± 0.16
15.05 ± 0.49
12.26 ± 0.13
-
New.ACC
59.19 ± 0.73
59.80 ± 0.50
60.21 ± 0.75
58.82 ± 0.38
58.97 ± 0.76
60.40 ± 0.55
59.94 ± 0.42
59.79 ± 0.63
-
Table 6: Comparison of Avg. ACC, Forgetting, and New ACC between our method and the baselines. The accuracy for each task is measured after training on the final task. We report the mean and standard deviation of each metric across different methods as mean±std . Results are obtained from three runs with distinct random seeds.
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
MAGE
62.10
-
-
-
-
-
62.10
43.56
68.35
-
-
-
-
55.96
41.25
78.37
31.26
-
-
-
50.29
57.29
75.18
32.02
37.09
-
-
50.40
55.84
70.56
31.75
34.10
68.74
-
52.20
Table 7: Detailed raw performance after training on each task of our proposed MAGE .
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
LoRA
59.68
-
-
-
-
-
59.68
20.10
65.19
-
-
-
-
42.65
18.94
78.80
31.18
-
-
-
42.97
50.26
71.32
31.26
41.22
-
-
48.52
36.75
66.43
30.94
29.28
66.60
-
46.00
Table 8: Detailed raw performance after training on each task of LoRA baseline.
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
MoELoRA
62.10
-
-
-
-
-
62.10
33.83
82.16
-
-
-
-
58.00
28.74
85.86
31.46
-
-
-
48.69
56.37
76.95
31.99
21.52
-
-
46.71
42.81
68.53
31.21
18.15
70.00
-
46.14
Table 9: Detailed raw performance after training on each task of MoELoRA baseline.
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
EWC
59.68
-
-
-
-
-
59.68
41.94
73.29
-
-
-
-
57.62
41.92
89.41
31.11
-
-
-
54.15
53.46
82.48
32.21
37.50
-
-
51.41
47.98
67.31
32.15
29.47
68.40
-
49.06
Table 10: Detailed raw performance after training on each task of EWC baseline.
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
LAE
59.68
-
-
-
-
-
59.68
42.28
77.49
-
-
-
-
59.89
40.50
88.81
31.18
-
-
-
53.50
55.50
83.29
32.04
27.48
-
-
49.58
42.36
79.53
31.87
26.28
65.72
-
49.15
Table 11: Detailed raw performance after training on each task of LAE baseline.
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
PGP
59.68
-
-
-
-
-
59.68
43.11
78.20
-
-
-
-
60.66
41.83
83.56
31.40
-
-
-
52.26
52.98
81.59
31.88
19.96
-
-
46.60
45.45
77.76
30.32
18.40
73.20
-
49.03
Table 12: Detailed raw performance after training on each task of PGP baseline.
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
CIA
59.68
-
-
-
-
-
59.68
45.66
68.95
-
-
-
-
57.31
40.98
79.12
31.08
-
-
-
50.39
51.33
77.38
31.50
41.06
-
-
50.32
42.79
72.27
30.89
35.29
70.28
-
50.30
Table 13: Detailed raw performance after training on each task of CIA baseline.
Method
Accuracy on Each Task
Avg.ACC( ↑ )
VQAv2
ImageNet
Flickr30k
OCRVQA
RefCOCO
HQEdit
RegLoRA
59.68
-
-
-
-
-
59.68
45.23
73.31
-
-
-
-
59.27
40.41
80.47
31.29
-
-
-
50.72
52.17
70.72
32.06
36.92
-
-
47.97
45.43
65.61
31.39
30.68
66.82
-
47.99
Table 14: Detailed raw performance after training on each task of RegLoRA baseline.
Figure 13: Visualized cases after training on each task of LoRA Fine-Tune baseline.