The importance of quantum decoherence in brain processes

Based on a calculation of neural decoherence rates, we argue that that the degrees of freedom of the human brain that relate to cognitive processes should be thought of as a classical rather than quantum system, i.e., that there is nothing fundamentally wrong with the current classical approach to neural network simulations. We find that the decoherence timescales ~10^{-13}-10^{-20} seconds are typically much shorter than the relevant dynamical timescales (~0.001-0.1 seconds), both for regular neuron firing and for kink-like polarization excitations in microtubules. This conclusion disagrees with suggestions by Penrose and others that the brain acts as a quantum computer, and that quantum coherence is related to consciousness in a fundamental way.Comment: Minor changes to match accepted PRE version. 15 pages with 5 figs included. Color figures and links at http://www.physics.upenn.edu/~max/brain.html or from [email protected]. Physical Review E, in pres

Program evaluation research: an experimental cost-effectiveness analysis of an armed robbery intervention program.

An armed robbery alarm system was implemented in 48 different stores in two separate geographical areas for 6 months and 12 months, respectively. The alarms were placed in the two separate areas at different times and all alarms were eventually removed. Thus, multiple baseline and reversal strategies were used to evaluate program impact. A device planted in a cash drawer was triggered whenever "bait" money was removed from the drawer sending an alarm signal directly to police cars and headquarters. On-scene apprehensions of armed robbers within target stores were greatly increased even though the armed robbery systems did not deter robbery incidents nor influence the court disposition of the cases. There was also no crime deterrence, crime displacement, or increased apprehensions in either the immediate neighborhoods of target stores or on a city-wide basis. The cost effectiveness of the program was calculated to be poor even though the program is being maintained because of the absence of an alternative robbery apprehension technology

Police and prosecution systems: An evaluation of a police criminal case preparation program

Program evaluation can provide objective information relevant to decisions on program maintenance. A program to address problems in the preparation of criminal investigation reports in a metropolitan police department was evaluated. The program permanently altered environmental conditions under which reports were prepared to facilitate performance. Police officers, who had previously prepared reports without assistance, visited the Case Preparation Room to prepare reports with assistance from office personnel. Compared to reports prepared without assistance, reports prepared in the Case Preparation Room documented more case elements required by the state legal code for criminal prosecution, were completed in fewer days following arrests, and received higher ratings from Assistant District Attorneys. Operation of a permanent program available to approximately 945 officers proved a practical solution to improving the preparation of criminal investigation reports