Octopuses are intelligent, soft-bodied animals with keen senses that perform reliably in a variety of visual and tactile learning tasks [1,2,3,4,5,6]. However, researchers have found them disappointing in that they consistently fail in operant tasks that require them to combine central nervous system reward information with visual and peripheral knowledge of the location of their arms [6,7,8]. Wells  claimed that in order to filter and integrate an abundance of multisensory inputs that might inform the animal of the position of a single arm, octopuses would need an exceptional computing mechanism, and There is no evidence that such a system exists in Octopus, or in any other soft bodied animal. Recent electrophysiological experiments, which found no clear somatotopic organization in the higher motor centers, support this claim . We developed a three-choice maze that required an octopus to use a single arm to reach a visually marked goal compartment. Using this operant task, we show for the first time that Octopus vulgaris is capable of guiding a single arm in a complex movement to a location. Thus, we claim that octopuses can combine peripheral arm location information with visual input to control goal-directed complex movements
Cephalopod mollusks are found virtually everywhere throughout the world's oceans. They are highly mobile invertebrates that have evolved behavioral and morphological defenses against vertebrate predators. Unlike other mollusks, the coleoid cephalopods (octopus, cuttlefish, and squid) possess highly developed nervous systems with huge brains equivalent in size to some vertebrate brains. Cephalopod intelligence is also exhibited by their impressive memory and learning abilities. Why have cephalopods developed such huge brains and cognitive ability? One of the keys to answering this question lies in understanding the social interactions of cephalopods, which have thus far not been well documented. In this paper, I will outline our recent behavioral experiments using mirrors with some cephalopods and discuss these experiments in light of the diversity of social and cognitive behaviors of cephalopods.
What is the distribution of cognitive ability within the animal kingdom? It would be egalitarian to assume that variation in intelligence is everywhere clinal, but examining trends among major phylogenetic groups, it becomes easy to distinguish high--performing ‘generalists’ – whose behavior exhibits domain--flexibility – from ‘specialists’ whose range of behavior is limited and ecologically specific. These generalists include mammals, birds, and, intriguingly, cephalopods. The apparent intelligence of coleoid cephalopods (squids, octopuses, and cuttlefish) is surprising – and philosophically relevant – because of our independent evolutionary lineages: the most recent common ancestor between vertebrates and cephalopods would have been a small wormlike organism, without any major organizational structure to its nervous system. By identifying the cognitive similarities between these organisms and vertebrates, we can begin to derive some general principles of intelligence as a biological phenomenon. Here, I discuss trends in cephalopod behavior and surrounding theory, and suggest their significance for our understanding of domain--general cognition and its evolution.
Analyzing the processes and neuronal circuitry involved in complex behaviors in phylogenetically remote species can help us understand the evolution and function of these systems. Cephalopods, with their vertebrate-like behaviors 1, 2, 3, 4 and 5 but much simpler brains , are ideal for such an analysis. The vertical lobe (VL) of Octopus vulgaris is a pivotal brain station in its learning and memory system . To examine the organization of the learning and memory circuitry and to test whether the LTP that we discovered in the VL  is involved in behavioral learning, we tetanized the VL to induce a global synaptic enhancement of the VL pathway. The effects of tetanization on learning and memory of a passive avoidance task were compared to those of transecting the same pathway. Tetanization accelerated and transection slowed short-term learning to avoid attacking a negatively reinforced object. However, both treatments impaired long-term recall the next day. Our results suggest that the learning and memory system in the octopus, as in mammals , is separated into short- and long-term memory sites. In the octopus, the two memory sites are not independent; the VL, which mediates long-term memory acquisition through LTP, also modulates the circuitry controlling behavior and short-term learning.
Cephalopods provide numerous examples of behavioral and neural plasticity and richness of the behavioral repertoire that has been claimed in favour of cognitive capabilities. Here we revise the most recent knowledge on octopus cognition and recognition processes. The examination of data and observations available provide the basis for asking new stimulating questions about the cognitive abilities of octopuses and their allies and open novel scenarios for future comparative research.
Cephalopod Consciousness Part 1: Who cares?I (Mike Lisieski) am an undergraduate student in Psychology and Pharmacology. I plan to pursue an M.D. and a Ph.D in behavioral neuroscience after finishing my undergraduate degrees. Cephalove is a project I started in May 2010 to make science related to cephalopods more accessible on the internet. Conveniently enough, it also gives me something entertaining to do that (hopefully) keeps my mind sharp. My background is in neuroscience and psychology, and so I tend to focus on these topics when discussing cephalopod research – though I try to give all disciplines a fair shake. I blogged for a few months at blogger, and then moved to the Southern Fried Science network, where I’m looking forward to blogging in a more visible location!
Cephalopods are a somewhat tangential research interest to me; I am generally interested in neuroscience and psychology, and more specifically in the neuroscience and psychology of psychoactive drugs. My first introduction to cephalopods in scientific research was through Fioritio and Scotto’s 1992 paper on observational learning in O. vulgaris, after which I discovered J. Z. Young’s work on cephalopod neuroanatomy. After casually reading these, and a visit to the Pittsburgh Zoo where I saw a beautiful O. dofleini crawling about its tank, I decided to start this blog. Prior to writing this blog, I have very little background in marine biology per se, although I have been interested in biology as long as I can remember.
Playing “Good Cop, Bad Cop” with Octopuses, The Scorpion and the Frog editorial from the 2010 experiment.Abstract
This study exposed 8 Enteroctopus dofleini separately to 2 unfamiliar individual humans over a 2-week period under differing circumstances. One person consistently fed the octopuses and the other touched them with a bristly stick. Each human recorded octopus body patterns, behaviors, and respiration rates directly after each treatment. At the end of 2 weeks, a body pattern (a dark Eyebar) and 2 behaviors (reaching arms toward or away from the tester and funnel direction) were significantly different in response to the 2 humans. The respiration rate of the 4 larger octopuses changed significantly in response to the 2 treatments; however, there was no significant difference in the 4 smaller octopuses' respiration. Octopuses' ability to recognize humans enlarges our knowledge of the perceptual ability of this nonhuman animal, which depends heavily on learning in response to visual information. Any training paradigm should take such individual recognition into consideration as it could significantly alter the octopuses' responses
Little is known about individual recognition (IR) in octopuses, although they have been abundantly studied for their sophisticated behaviour and learning capacities. Indeed, the ability of octopuses to recognise conspecifics is suggested by a number of clues emerging from both laboratory studies (where they appear to form and maintain dominance hierarchies) and field observations (octopuses of neighbouring dens display little agonism between each other). To fill this gap in knowledge, we investigated the behaviour of 24 size-matched pairs of Octopus vulgaris in laboratory conditions.
The experimental design was composed of 3 phases: Phase 1 (acclimatization): 12 “sight-allowed” (and 12 “isolated”) pairs were maintained for 3 days in contiguous tanks separated by a transparent (and opaque) partition to allow (and block) the vision of the conspecific; Phase 2 (cohabitation): members of each pair (both sight-allowed and isolated) were transferred into an experimental tank and were allowed to interact for 15 min every day for 3 consecutive days; Phase 3 (test): each pair (both sight-allowed and isolated) was subject to a switch of an octopus to form pairs composed of either familiar (“sham switches”) or unfamiliar conspecifics (“real switches”). Longer latencies (i.e. the time elapsed from the first interaction) and fewer physical contacts in the familiar pairs as opposed to the unfamiliar pairs were used as proxies for recognition.
Octopuses appear able to recognise conspecifics and to remember the individual previously met for at least one day. To the best of our knowledge, this is the first experimental study showing the occurrence of a form of IR in cephalopods. Future studies should clarify whether this is a “true” IR.