Recent Publications (2017-2018)
Hennessee, J.P., Castel, A.D., & Knowlton, B.J. (2017) Recognizing what matters: Value improves recognition by selectively enhancing recollection. Journal of Memory and Language. 94:195-205.
This paper shows that items that are more deemed more valuable at study are later recognized more accurately, and this benefit is just about entirely an enhancement of recollection for the valuable items. Even though recollection is increased for valuable items, memory for incidental details (i.e. font color) about these items was surprisingly worse than for recollected low value items. It may be that value enhances attentional focus on the item at the expense of irrelevant information
Knowlton, B.J., Siegel, A.L.M., & Moody, T.D. (2017) Procedural Learning in Humans. In J.H. Byrne, (ed.) Learning and Memory: A Comprehensive Reference, 2nd Edition, Volume 3: Memory Systems, Elsevier, Amsterdam, pp 295-312.
This review covers recent theoretical advances in the study of learning skills, habits, and other procedures in people. This chapter appeared in Volume 3 (Memory Systems) of this second edition that was published this summer. This volume was edited by the late Howard Eichenbaum, who was an outstanding scientist and colleague.
Cohen, M.S., Rissman, J., Hovhannisyan, M., Castel, A.D., & Knowlton, B.J. (2017). Free recall test experience potentiates strategy-driven effects of value on memory. Journal of Experimental Psychology: Learning, Memory, & Cognition 43:1581-1601.
This paper presents the idea that there are both strategic and automatic effects of value on subsequent memory. Whether or not subjects had some experience with studying lists and having to do free recall tests was a major factor in whether subjects were strategic- If you realize that you can only recall a small amount of available information, you may actively avoid studying low value information. This would lead to comparatively more recollection and familiarity for high value items, However, without this experience, value enhanced recollection only; this may reflect a more automatic strengthening of encoding by value.
Hennesse, J.P., Castel, A.D., & Knowlton, B.J. (2018). The effects of value on context-item associative memory in older adults. Psychology and Aging. 33:46-56.
This paper appears in the special issue of Psychology and Aging on associative memory. The results show that valuable items are remembered better by younger and older adults, but that memory for contextual details associated with these items may be impaired relative to less valuable items. While older adults often show preserved memory for valuable items. this may come at a cost to memory for incidental detail.
Knowlton, B.J. & Patterson, T.K. (2018). Habit formation in the striatum. Current Topics in Behavioral Neurosciences. 37:275-295.
This review article discusses current research in humans and animal models for conditions that favor the shift from actions to habits.
Lee, J., Nuechterlein, K., Knowlton, B., Bearden, C., Cannon, T., Fiske, A., Ghermezi, L., Hayata, J., Hellemann, G., Horan, W., Kee, K., Kern, R., Subotnik, K., Sugar, C., Ventura, J., Yee-Bradbury, C., & Green, M. (2018). Episodic memory for dynamic social interaction across phase of illness in schizophrenia. Schizophrenia Bulletin, 44:620-630.
This was a collaborative study from the UCLA Center for Neurocognition and Emotion in Schizophrenia involving labs at the Greater Los Angeles VA, the Semel Institute at UCLA and the Dept. of Psychology. We found impaired recollection for elements of social interactions in patients with schizophrenia or those at high risk of developing the disease. It is very possible that such memory difficulties contribute to problems with social interactions that occur in these patients. See the UCLA press release below
Patterson, T.K. & Knowlton B.J. (2018). Specificity in human striatal habit learning: A meta-analytic review. Current Opinion in Behavioral Science. 20:75-82.
This paper will appear in an upcoming issue of Current Opinion in Behavioral Science on “Habits and Skills”. This paper describes a meta-analysis comparing the locus of activation across a number of different habit learning paradigms. The results suggest that activations from tasks that best fit the criteria for habits are centered around the putamen.
Perugini, A., Ditterich, J., Shaikh, A.G., Knowlton, B.J., & Basso, M.A. (2018). Paradoxical decision-making: A framework for understanding cognitive deficits in Parkinson’s disease. Trends in Neurosciences. 41:512-525
This review paper was a collaborative effort with Michelle Basso in the UCLA Semel Institute. In it, we discuss evidence of an impairment in the integration of memory and sensory information in decision-making in Parkinson’s disease, and that this deficit can lead to the pattern of cognitive deficits displayed by these patients.
Reggente, N., Cohen, M.S., Zheng, Z.S., Castel, A.D., Knowlton, B.J., Rissman, J. (2018). Memory recall for high reward value items correlates with individual differences in white matter pathways associated with reward processing and fronto-temporal communication. Frontiers in Human Neuroscience. 12:241
This paper resulted from a collaborative effort with the Rissman lab that used diffusion tensor imaging to examine the relationship between memory for high-value items and integrity of tracts related to memory and reward processing. We found that fractional anisotropy of the uncinate fasiculus was related to the number of high value items recalled,. Furthermore, we found that selectivity for high over low value items in memory was related to the number of fibers connecting the nucleus accumbens and ventral tegmental area, implicating reward circuitry.
Lin CJ, Yang HC, Knowlton BJ, Wu AD, Iacoboni M, Ye YL, Huang SL, Chiang MC. (2018). Contextual interference enhances motor learning through increased resting brain connectivity during memory consolidation. Neuroimage, 181:1-15.
This paper resulted from the continued collaboration between UCLA and the National Yang-Ming University in Taipei. The goal of this work is to characterize why interleaved practice of motor skills leads to better learning. The results showed that the advantage of interleaved practice was related to greater functional connectivity between the premotor cortex and cerebellum, medial temporal regions, putamen, and thalamus after initial practice. This enhanced connectivity was related to increased functional activation during subsequent training, and may reflect early consolidation of motor skill.
Clayson, P. E., Kern, R. S., Nuechterlein, K. H., Knowlton, B. J., Bearden, C. E., Cannon, T. D., Fiske, A. P., Ghermezi, L., Hayata, J. N., Hellemann, G. S., Horan, W. P., Kee, K., Lee, J., Subotnik, K. L., Sugar, C. A., Ventura, J., Yee, C. M., & Green, M. F. (2018). Social vs. non-social measures of learning potential for predicting community functioning across phase of illness in schizophrenia. Schizophrenia Research. 18:30492-30494,
This is another paper from the UCLA Center for Neurocognition and Emotion in Schizophrenia. The main findings were that initial scores on the Wisconsin Card Sorting task and a measure of social cognition were predictive of community functioning in patients with chronic or first-episode schizophrenia. While patients showed a benefit of training on both of these measures, the amount of benefit (learning potential) was not significantly related to community functioning.