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Correlates of reward-predictive value in learning-related hippocampal neural activity.

Okatan M - Hippocampus (2009)

Bottom Line: The results suggest that information about correct associations may be expressed in the hippocampus before it is detected in the behavior of a subject.In this way, the hippocampus may be among the earliest brain areas to express learning and drive the behavioral changes associated with learning.These potential functions are discussed in connection with hippocampal cell assembly sequences and their reverse reactivation during the awake state.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Cognitive Neurobiology, Department of Psychology, Boston University, Boston, MA 02215, USA. okatan@bu.edu

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Learning-related hippocampal neural activity and reward-predictive value. The average firing rates (red) of a sustained-changing cell (A) and a baseline-sustained changing cell (B) relative to baseline. The legend shows the reward-schedules used in fitting the data. Maximum likelihood estimates for the best fits (solid black curves): (A) ; (B) . The white and the black dots at the top of each graph indicate the incorrect and the correct responses of the subject, respectively. The estimated learning and neural change trials for these cases were 25 and 26 (A), 9 and 19 (B), respectively (Wirth et al., 2003). The firing rate increases in (A) (P = 0.01) and decreases in (B) (P = 0.03) before the estimated learning trial according to the slope test (see section “Slope of neural change before learning” for Methods). Data extracted from Figure 2 of Wirth et al., Science, 2003, 300, 1578–1581, © American Association for the Advancement of Science.
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fig02: Learning-related hippocampal neural activity and reward-predictive value. The average firing rates (red) of a sustained-changing cell (A) and a baseline-sustained changing cell (B) relative to baseline. The legend shows the reward-schedules used in fitting the data. Maximum likelihood estimates for the best fits (solid black curves): (A) ; (B) . The white and the black dots at the top of each graph indicate the incorrect and the correct responses of the subject, respectively. The estimated learning and neural change trials for these cases were 25 and 26 (A), 9 and 19 (B), respectively (Wirth et al., 2003). The firing rate increases in (A) (P = 0.01) and decreases in (B) (P = 0.03) before the estimated learning trial according to the slope test (see section “Slope of neural change before learning” for Methods). Data extracted from Figure 2 of Wirth et al., Science, 2003, 300, 1578–1581, © American Association for the Advancement of Science.

Mentions: For a given pair of α and γ, Eqs. (2)–(4) are iterated using one of the following three reward schedules: rk(T) = nk, rk(T) = 1, or rk(T) = 0, where the time T indicates the end of the trial and nk is the outcome of a subject's behavioral response such that nk = 1 if the response is correct, and nk = 0 otherwise, as shown in Figure 2. The reward signal is zero at all other times.


Correlates of reward-predictive value in learning-related hippocampal neural activity.

Okatan M - Hippocampus (2009)

Learning-related hippocampal neural activity and reward-predictive value. The average firing rates (red) of a sustained-changing cell (A) and a baseline-sustained changing cell (B) relative to baseline. The legend shows the reward-schedules used in fitting the data. Maximum likelihood estimates for the best fits (solid black curves): (A) ; (B) . The white and the black dots at the top of each graph indicate the incorrect and the correct responses of the subject, respectively. The estimated learning and neural change trials for these cases were 25 and 26 (A), 9 and 19 (B), respectively (Wirth et al., 2003). The firing rate increases in (A) (P = 0.01) and decreases in (B) (P = 0.03) before the estimated learning trial according to the slope test (see section “Slope of neural change before learning” for Methods). Data extracted from Figure 2 of Wirth et al., Science, 2003, 300, 1578–1581, © American Association for the Advancement of Science.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2742500&req=5

fig02: Learning-related hippocampal neural activity and reward-predictive value. The average firing rates (red) of a sustained-changing cell (A) and a baseline-sustained changing cell (B) relative to baseline. The legend shows the reward-schedules used in fitting the data. Maximum likelihood estimates for the best fits (solid black curves): (A) ; (B) . The white and the black dots at the top of each graph indicate the incorrect and the correct responses of the subject, respectively. The estimated learning and neural change trials for these cases were 25 and 26 (A), 9 and 19 (B), respectively (Wirth et al., 2003). The firing rate increases in (A) (P = 0.01) and decreases in (B) (P = 0.03) before the estimated learning trial according to the slope test (see section “Slope of neural change before learning” for Methods). Data extracted from Figure 2 of Wirth et al., Science, 2003, 300, 1578–1581, © American Association for the Advancement of Science.
Mentions: For a given pair of α and γ, Eqs. (2)–(4) are iterated using one of the following three reward schedules: rk(T) = nk, rk(T) = 1, or rk(T) = 0, where the time T indicates the end of the trial and nk is the outcome of a subject's behavioral response such that nk = 1 if the response is correct, and nk = 0 otherwise, as shown in Figure 2. The reward signal is zero at all other times.

Bottom Line: The results suggest that information about correct associations may be expressed in the hippocampus before it is detected in the behavior of a subject.In this way, the hippocampus may be among the earliest brain areas to express learning and drive the behavioral changes associated with learning.These potential functions are discussed in connection with hippocampal cell assembly sequences and their reverse reactivation during the awake state.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Cognitive Neurobiology, Department of Psychology, Boston University, Boston, MA 02215, USA. okatan@bu.edu

Show MeSH
Related in: MedlinePlus