PMID- 1967830
OWN - NLM
STAT- MEDLINE
DCOM- 19900306
LR  - 20190501
IS  - 0027-8424 (Print)
IS  - 1091-6490 (Electronic)
IS  - 0027-8424 (Linking)
VI  - 87
IP  - 2
DP  - 1990 Jan
TI  - Application of entropy measures derived from the ergodic theory of dynamical 
      systems to rat locomotor behavior.
PG  - 723-7
AB  - Measures of complexity derived from ergodic theory of dynamical systems were 
      developed and applied to an exemplary data set describing locomotor movements of 
      rats in a bounded space. A symbolic dynamical system was obtained by partitioning 
      the event space into equally probable partition elements, using a k-dimensional 
      tree. The measures calculated from the symbolic sequences included the 
      topological entropy (ht)--i.e., the rate of increase of all possible sequences 
      with increasing sequence length--and the metric entropy (hm)--i.e., the rate of 
      increase of all likely sequences with increasing sequence length. These measures 
      were used to assess changes in rat locomotor behavior as recorded in the 
      behavioral pattern monitor (BPM) that were induced by amphetamine (0.25, 0.50, 
      1.0, or 2.0 mg/kg) and 3,4-methylenedioxymethamphetamine (MDMA; 1.25, 2.5, 5.0, 
      or 10.0 mg/kg). Amphetamine increased the mean activity, ht, and hm. MDMA 
      resulted in a monotonic dose-response curve for activity but exhibited a biphasic 
      dose response in ht and hm. In particular, some animals in the higher dose groups 
      showed a ht in the range of the saline controls, whereas other animals exhibited 
      a significantly reduced ht and a greater decrease in hm, suggesting that two 
      different behavioral reactions coexist within the same higher dose range of MDMA. 
      An important implication of our method is that, in applied ergodic 
      measure-theoretic approaches, the partition that determines the elements of the 
      symbolic dynamical system should not be specified a priori on abstract 
      mathematical grounds but should be chosen relative to its significance with 
      respect to the data set in question. Here, the animal constructs its own 
      spatiotemporal partition in behavioral phase space.
FAU - Paulus, M P
AU  - Paulus MP
AD  - Laboratory of Biological Dynamics and Theoretical Medicine, School of Medicine, 
      University of California, San Diego, La Jolla 92093.
FAU - Geyer, M A
AU  - Geyer MA
FAU - Gold, L H
AU  - Gold LH
FAU - Mandell, A J
AU  - Mandell AJ
LA  - eng
GR  - DA02925/DA/NIDA NIH HHS/United States
GR  - MH00188/MH/NIMH NIH HHS/United States
GR  - MH16109/MH/NIMH NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (Designer Drugs)
RN  - 4764-17-4 (3,4-Methylenedioxyamphetamine)
RN  - KE1SEN21RM (N-Methyl-3,4-methylenedioxyamphetamine)
RN  - TZ47U051FI (Dextroamphetamine)
SB  - IM
MH  - 3,4-Methylenedioxyamphetamine/analogs & derivatives/pharmacology
MH  - Animals
MH  - Designer Drugs
MH  - Dextroamphetamine/pharmacology
MH  - Male
MH  - Mathematics
MH  - *Models, Neurological
MH  - *Motor Activity/drug effects
MH  - N-Methyl-3,4-methylenedioxyamphetamine
MH  - Rats
MH  - Rats, Inbred Strains
MH  - Reference Values
PMC - PMC53338
EDAT- 1990/01/01 00:00
MHDA- 1990/01/01 00:01
PMCR- 1990/07/01
CRDT- 1990/01/01 00:00
PHST- 1990/01/01 00:00 [pubmed]
PHST- 1990/01/01 00:01 [medline]
PHST- 1990/01/01 00:00 [entrez]
PHST- 1990/07/01 00:00 [pmc-release]
AID - 10.1073/pnas.87.2.723 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 1990 Jan;87(2):723-7. doi: 10.1073/pnas.87.2.723.