The cambridge declaration on consciousness on this

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The Cambridge Declaration on Consciousness - On this day of July 7, 2012, a prominent international group of cognitive neuroscientists, neuropharmacologists, neurophysiologists, neuroanatomists and computational neuroscientists gathered at The University of Cambridge to reassess the neurobiological substrates of conscious experience and related behaviors in human and non-human animals. - They are proclaiming their support for the idea that animals are conscious and aware to the degree that humans are — a list of animals that includes all mammals, birds, and even the octopus. But will this make us stop treating these animals in totally inhumane ways? Blindsight - ‘Blindsight’ - Weiskrantz, 1986 - Visual capacities in scotoma - D.B. had headaches from the age of 14 eventually relieved by removing part of visual cortex… leaving scotoma - Weiskrantz called in to check his vision found he could ‘guess’ the orientation of a stick, point to a target, reach for a outstretched hand - He could ‘see’ things he was not aware of! Visual Spatial Neglect - Caused by damage to the Parietal Lobe - Impairs ability to attend to the side of space that is opposite of the damaged hemisphere - The vision is normal, but the attention is impaired. - For example, a patient only eats food from the same side of plate as damage. Biological rhythm types
- Circadian o Any rhythmic change that continues at close to a 24-hour cycle in the absence of 24- hour cues body temperature cortisol secretion sleep and wakefulness o Infradian – occurs less than once a day o Ultradian – occurs more than once a day o In the absence of time cues, the cycle period will become somewhat longer than 24 hours - Circalunar – menstruation; circannual – migration of birds/hibernation at winter/weight gain in winter/ SAD because of less light Examples of Human Circadian Rhythms Function Typical Circadian Rhythm Peak mental alertness and memory functions two peaks: around 9 AM and 9 PM Lowest body temperature about 36.2: around 3 to 4 AM Highest body temperature about 37.2: around 5 to 6 PM Peak physical strength two peaks: around 11 AM and 7 PM Peak hearing, visual, taste, and smell sensitivity two peaks: around 3 AM and 6 PM Lowest sensitivity to pain around 3 to 5 PM Peak sensitivity to pain around 3 to 5 AM Peak degree of sleepiness two peaks: around 3 AM and 3 pm Peak melatonin hormone in blood between 1 and 3 AM Isolation studies - Jurgen Aschoff in Germany - Isolation experiments. Subjects placed in an underground bunker and allowed to turn lights on or off when they wanted.
- Aschoff tracked their sleep-wake cycles, body temperature, and other physiological and behavioral variables. - He concluded that humans have endogenous circadian cycles. - Isolation studies: Typically, humans show freerunning rhythms with periods ~ 25 hr - Siffre (1972) - – speleologist - – lived in a cave for 7 months - – no time cues - – mentally lost 25 days! Conclusion: We have internal clocks but we also need time cues (light) to reset them. Zeitgebers – time cues, external or environmental cues to entrain biological rhythms

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