When processing of stimuli occurs without attention, phenomenal experience, as well as cognitive access, may be lost. Sensory representations are, however, constructed by neural machinery extending far beyond sensory receptors. In conditions such as cerebral achromatopsia incomplete sensory representations may still elicit phenomenal experience but these representations might be too aberrant to be integrated into the wider cognitive workspace.

By themselves, mesencephalic subcortical mechanisms provide a preattentive kind of consciousness, related to stimulus-related, short-latency dopamine release triggered by collicular input. Elaborate forms of consciousness, containing identifiable objects (visual, auditory, tactile, or chemical), imply longer-lasting phenomena that depend on the activation of prosencephalic networks. Nevertheless, the maintenance of these higher-level networks strongly depends on long-lasting mesencephalic dopamine release.

In a dynamic world, mechanisms allowing prediction of future situations can provide a selective advantage. We suggest that memory systems differ in the degree of flexibility they offer for anticipatory behavior and put forward a corresponding taxonomy of prospection. The adaptive advantage of any memory system can only lie in what it contributes for future survival. The most flexible is episodic memory, which we suggest is part of a more general faculty of mental time travel that allows us not only to go back in time, but also to foresee, plan, and shape virtually any specific future event. We review comparative studies and find that, in spite of increased research in the area, there is as yet no convincing evidence for mental time travel in nonhuman animals. We submit that mental time travel is not an encapsulated cognitive system, but instead comprises several subsidiary mechanisms. A theater metaphor serves as an analogy for the kind of mechanisms required for effective mental time travel. We propose that future research should consider these mechanisms in addition to direct evidence of future-directed action. We maintain that the emergence of mental time travel in evolution was a crucial step towards our current success.

Dijkerman & de Haan (D&dH) argue that body image and body schema form parts of different and dissociable somatosensory streams. We agree in general, but believe that more emphasis should be placed on interactions between these two streams. We illustrate this point with evidence from the rubber-hand illusion (RHI) – an illusion of body image, which depends critically upon body schema.

Although the authors' ingenuity in identifying criteria for innovation for field studies is appealing, most field studies will lack adequate data. Additionally, their definition does not clearly distinguish innovation from individual learning and is vague about cognitive mechanisms involved. We suggest that developmental data are essential to identifying the causes and consequences of learning new behaviors.

We agree with Block's basic hypothesis postulating the existence of phenomenal consciousness without cognitive access. We explain such states in terms of consciousness without top-down, endogenous attention and speculate that their correlates may be a coalition of neurons that are consigned to the back of cortex, without access to working memory and planning in frontal cortex.

Foresight requires not only scenarios constructed from memories, but also adequate incentive to let these scenarios compete with current rewards. This incentive probably comes from the efficacy of the scenarios in occasioning present emotions, which depends not on their accuracy per se but on their uniqueness as compared with other possible occasions for emotion.

We contend that Ramsey et al.'s definition of animal innovation sensu process may be partially misleading when investigating mechanisms underlying animal innovation. By excluding social learning from the “process” of innovation, they may be reproducing a dichotomous schema that does not accurately correspond to our knowledge of the acquisition of novel behavioral variants. This gives us some reason to doubt the functional specification of the defined process of innovation.

Postulating the subcortical organization of human consciousness provides a critical link for the construal of pain in patients with impaired cortical function or cortical immaturity during early development. Practical implications of the centrencephalic proposal include the redefinition of pain, improved pain assessment in nonverbal humans, and benefits of adequate analgesia/anesthesia for these patients, which certainly justify the rigorous scientific efforts required.

The model developed in the target article is not as comprehensive as might be desired on two counts: (1) in that how the transition from proximal stimulation at the skin gives rise to the perception of external objects is taken for granted; and (2) in that another population of participants, the blind, constitute an important group from which we can understand somatosensory processing and neural plasticity.

Our model of haptic object recognition points to the importance of material, as well as geometric properties of objects. Collectively, these can elicit a recognition response after an initial contact, without sequential exploration. This model suggests a revision of the authors' proposals, which takes into account an individual's intention – whether it is for perception or action – and the extent of exploratory movement.

Attention research with prefrontal patients supports Merker's argument regarding the crucial role for the midbrain in higher cognition, through largely overlooked and misunderstood prefrontotectal connectivity. However, information theoretic analyses reveal that both exogenous (i.e., collicular) and endogenous (prefrontal) sources of information are responsible for large-scale context-sensitive brain dynamics, with prefrontal cortex being at the top of the hierarchy for cognitive control.

Acting in the present in anticipation of the future is argued to be a behavioral correlate of mental time travel (MTT). Yet, it is important to consider how other future-directed behaviors – including planning, delay of gratification, and acts of prospective memory – figure into a theory of MTT and future thinking more broadly. Developmental science can help in this formulation.

The commentaries have both drawn out the implications of, and challenged, our definition and operationalization of innovation. In this response, we reply to these concerns, discuss the differences between our operationalization and the preexisting operationalization if innovation, and make suggestions for the advancement of the challenging and exciting field of animal innovation.

The dissociation Block provides between phenomenal and access consciousness (P-consciousness and A-consciousness) captures much of our intuition about conscious experience. However, it raises a major methodological puzzle, and is not uniquely supported by the empirical evidence. We provide an alternative interpretation based on the notion of levels of representation and partial awareness.

The claim that nonhuman animals lack foresight is common and intuitive. I propose an alternative whereby foresight is a gradual continuum in that it is present in animals to the extent that it is needed. A second aspect of this commentary points out that the requirements that the memory that mediates foresight be both specific yet flexible seem contradictory.

The insight that, in terms of behaviour control, the mesodiencephalic system is superordinate to the cortex should have profound implications for behavioural sciences. Nevertheless, the thalamocortical system could still be deemed an “organ of consciousness” if we came to accept that consciousness is not central to purposeful behaviour, in accordance with instinct theory. Philosophically, Merker's concepts of basic consciousness and ego-centre warrant critical discussion.

Block makes a case for the existence of conscious experience without access. His case would have been much stronger, however, if he had woven fully unconscious processing into the “mesh argument,” and considered arguments that are intrinsic to neuroscience.

Somatosensory processing for action guidance can be dissociated from perception and memory processing. The dorsal system has a global bias and the ventral system has a local processing bias. Autistics illustrate the point, showing a bias for part over wholes. Lateralized differences have also been noted in these modalities. The multi-modal dysfunction observed may suggest more an issue of interhemispheric communication.

Dijkerman & de Haan (D&dH) study perception and action as two independent processes. However, in all daily activities the processes are completely intertwined, so it is difficult to separate one from the other. Humans perceive in order to move and also move in order to perceive. Understanding first how perception and action are coordinated, leads us then to determine how each component works independently.