Octopus Consciousness: The Role of Perceptual Richness

It is always difficult to even advance possible dimensions of consciousness, but Birch et al., 2020 have suggested four possible dimensions and this review discusses the first, perceptual richness, with relation to octopuses. They advance acuity, bandwidth, and categorization power as possible components. It is first necessary to realize that sensory richness does not automatically lead to perceptual richness and this capacity may not be accessed by consciousness. Octopuses do not discriminate light wavelength frequency (color) but rather its plane of polarization, a dimension that we do not understand. Their eyes are laterally placed on the head, leading to monocular vision and head movements that give a sequential rather than simultaneous view of items, possibly consciously planned. Details of control of the rich sensorimotor system of the arms, with 3/5 of the neurons of the nervous system, may normally not be accessed to the brain and thus to consciousness. The chromatophore-based skin appearance system is likely open loop, and not available to the octopus’ vision. Conversely, in a laboratory situation that is not ecologically valid for the octopus, learning about shapes and extents of visual figures was extensive and flexible, likely consciously planned. Similarly, octopuses’ local place in and navigation around space can be guided by light polarization plane and visual landmark location and is learned and monitored. The complex array of chemical cues delivered by water and on surfaces does not fit neatly into the components above and has barely been tested but might easily be described as perceptually rich. The octopus’ curiosity and drive to investigate and gain more information may mean that, apart from richness of any stimulus situation, they are consciously driven to seek out more information. This review suggests that cephalopods may not have a similar type of intelligence as the ‘higher’ vertebrates, they may not have similar dimensions or contents of consciousness, but that such a capacity is present nevertheless.

Optical Rotation Approach to Search for the Electric Dipole Moment of the Electron

The P , T -odd Faraday effect (i.e., rotation of the polarization plane of light propagating through a medium in presence of the external electric field due to P , T symmetry violating interactions) is considered for several atomic species: Ra, Pb, Tl, Hg, Cs, and Xe. Corresponding theoretical simulation of P , T -odd Faraday experiment, with already achieved intracavity absorption spectroscopy characteristics and parameters, is performed. The results show that the magnetic dipole transitions in the Tl and Pb atoms as well as the electric dipole transitions in the Ra, Hg and Cs atoms are favorable for the observation of the P , T -odd Faraday optical rotation. The estimation of the rotation angle of the light polarization plane demonstrates that recently existing boundaries for the electron electric dipole moment can be improved by one-two orders of magnitude.

Оптический эффект вращения плоскости поляризации света в ДНК-содержащих материалах

Using the example of DNA water solutions, a manifestation of the light polarization plane rotation effect has been shown (in comparison with a number of dyes). Numerical values of the rotation angle have been established that significantly exceed those for water solutions of dyes and sugar traditionally used in saccharimeters and polarimeters. Therefore, another optical effect in biostructuring optical materials has been identified and confirmed.

Магнитооптические свойства висмутзамещенных пленок ферритов-гранатов в сильных импульсных магнитных полях

—A technique of measuring the rotation of the light polarization plane in pulsed magnetic fields with strength up to 40 T with a sensitivity of 0.1° is proposed. The Faraday effect has been studied in films of diluted ferrites—garnets (Lu,Bi)_3(Fe,Ga,Al)_5O_12 in the temperature range from room temperature to 78 K, including the vicinity of the magnetic moment compensation temperature. The transition to the noncollinear phase in the magnetic phase diagram is shown to occur at a magnetic field strength higher than 30 T at room temperature, and the threshold transition field tends to zero when approaching the magnetic moment compensation temperature.

Experimental Research on Measuring Two-Dimensional Stress Field Using Digital Holographic Photo-Elastic Method

According to the holographic optical theory, based on the method of rotating reference light polarization plane, through the simultaneous solution of light intensity equations transformed by the hologram, the digital holographic nondestructive testing of two-dimensional stress field is introduced. This technology does not require additional experimental means and numerical method for separate fringes, determining fringe order and solving stress. It is a convenient, accurate and non-destructive measurement of two-dimensional stress field. The paper first introduces the basic theory of digital holographic photo-elastic method, and then verifies it by experiments and simulation. Light intensity images are obtained through the comparative experiments and theoretical solutions. The results prove the strong feasibility of the method in experiments, and lay the foundation for further experimental study.