Decision Making in Plants: A Rooted Perspective.

This article discusses the possibility of plant decision making. We contend that recent work on bacteria provides a pertinent perspective for thinking about whether plants make choices. Specifically, the analogy between certain patterns of plant behaviour and apparent decision making in bacteria provides principled grounds for attributing decision making to the former. Though decision making is our focus, the discussion has implications for the wider issue of whether and why plants (and non-neural organisms more generally) are appropriate targets for cognitive abilities. Moreover, decision making is especially relevant to the issue of plant intelligence as it is commonly taken to be characteristic of cognition.

Consciousness and cognition in plants.

Unlike animal behavior, behavior in plants is traditionally assumed to be completely determined either genetically or environmentally. Under this assumption, plants are usually considered to be noncognitive organisms. This view nonetheless clashes with a growing body of empirical research that shows that many sophisticated cognitive capabilities traditionally assumed to be exclusive to animals are exhibited by plants too. Yet, if plants can be considered cognitive, even in a minimal sense, can they also be considered conscious? Some authors defend that the quest for plant consciousness is worth pursuing, under the premise that sentience can play a role in facilitating plant's sophisticated behavior. The goal of this article is not to provide a positive argument for plant cognition and consciousness, but to invite a constructive, empirically informed debate about it. After reviewing the empirical literature concerning plant cognition, we introduce the reader to the emerging field of plant neurobiology. Research on plant electrical and chemical signaling can help shed light into the biological bases for plant sentience. To conclude, we shall present a series of approaches to scientifically investigate plant consciousness. In sum, we invite the reader to consider the idea that if consciousness boils down to some form of biological adaptation, we should not exclude a priori the possibility that plants have evolved their own phenomenal experience of the world. This article is categorized under: Cognitive Biology > Evolutionary Roots of Cognition Philosophy > Consciousness Neuroscience > Cognition.

Agency From a Radical Embodied Standpoint: An Ecological-Enactive Proposal.

Explaining agency is a significant challenge for those who are interested in the sciences of the mind, and non-representationalists are no exception to this. Even though both ecological psychologists and enactivists agree that agency is to be explained by focusing on the relation between the organism and the environment, they have approached it by focusing on different aspects of the organism-environment relation. In this paper, I offer a suggestion for a radical embodied account of agency that combines ecological psychology with recent trends in enactive cognitive science. According to this proposal, while enactivism focuses primarily on describing how our acquired sensorimotor schemes and habits mutually equilibrate, affecting our tendency to act upon some affordances instead of others, ecological psychology focuses on studying how perceptual information contributes to the actualization of the sensorimotor schemes and habits without mediating representations, inferences, and computations. The paper concludes by briefly exploring how this ecological-enactive theory of agency can account for how socio-cultural norms shape human agency.

Distal engagement: Intentions in perception.

Non-representational approaches to cognition have struggled to provide accounts of long-term planning that forgo the use of representations. An explanation comes easier for cognitivist accounts, which hold that we concoct and use contentful mental representations as guides to coordinate a series of actions towards an end state. One non-representational approach, ecological-enactivism, has recently seen several proposals that account for "high-level" or "representation-hungry" capacities, including long-term planning and action coordination. In this paper, we demonstrate the explanatory gap in these accounts that stems from avoiding the incorporation of long-term intentions, as they play an important role both in action coordination and perception on the ecological account. Using recent enactive accounts of language, we argue for a non-representational conception of intentions, their formation, and their role in coordinating pre-reflective action. We provide an account for the coordination of our present actions towards a distant goal, a skill we call distal engagement. Rather than positing intentions as an actual cognitive entity in need of explanation, we argue that we take them up in this way as a practice due to linguistically scaffolded attitudes towards language use.

Misplacing memories? An enactive approach to the virtual memory palace.

In this paper, we evaluate the pragmatic turn towards embodied, enactive thinking in cognitive science, in the context of recent empirical research on the memory palace technique. The memory palace is a powerful method for remembering yet it faces two problems. First, cognitive scientists are currently unable to clarify its efficacy. Second, the technique faces significant practical challenges to its users. Virtual reality devices are sometimes presented as a way to solve these practical challenges, but currently fall short of delivering on that promise. We address both issues in this paper. First, we argue that an embodied, enactive approach to memory can better help us understand the effectiveness of the memory palace. Second, we present design recommendations for a virtual memory palace. Our theoretical proposal and design recommendations contribute to solving both problems and provide reasons for preferring an embodied, enactive account over an information-processing treatment of the memory palace.

Are plants cognitive? A reply to Adams.

According to F. Adams [this journal, vol. 68, 2018] cognition cannot be realized in plants or bacteria. In his view, plants and bacteria respond to the here-and-now in a hardwired, inflexible manner, and are therefore incapable of cognitive activity. This article takes issue with the pursuit of plant cognition from the perspective of an empirically informed philosophy of plant neurobiology. As we argue, empirical evidence shows, contra Adams, that plant behavior is in many ways analogous to animal behavior. This renders plants suitable to be described as cognitive agents in a non-metaphorical way. Sections two to four review the arguments offered by Adams in light of scientific evidence on plant adaptive behavior, decision-making, anticipation, as well as learning and memory. Section five introduces the 'phyto-nervous' system of plants. To conclude, section six resituates the quest for plant cognition into a broader approach in cognitive science, as represented by enactive and ecological schools of thought. Overall, we aim to motivate the idea that plants may be considered genuine cognitive agents. Our hope is to help propel public awareness and discussion of plant intelligence once appropriately stripped of anthropocentric preconceptions of the sort that Adams' position appears to exemplify.

Outcome of graft failure after allogeneic stem cell transplant: study of 89 patients.

Strategies for reversing graft failure (GF) after allogeneic stem cell transplant (SCT) depend on the options available in each situation. GF was reported in 16 Spanish institutions from January 2006 to July 2011. Primary GF was defined as an absolute neutrophil count (ANC) > 0.5 × 10(9)/L not reached by day + 28 after SCT from peripheral blood (PB) or bone marrow (BM) progenitors and by day + 42 after SCT from unrelated cord blood (UCB) progenitors. Secondary GF was defined as a recurrent ANC < 0.5 × 10(9)/L. Eighty-nine patients with GF were reported, and 80 patients received a second SCT. The 5-year survival probability was 31% (95% confidence interval [CI]: 18-44%), and the incidences of non-relapse mortality and relapse estimated by competing risks were 47% (95% CI: 36-58%) and 21% (95% CI: 4-28%). The strategy adopted to treat GF was heterogeneous, and no approach could be unequivocally recommended for this situation. The prognosis of patients with GF was poor even after successful recovery from GF.

Revaccination with measles, tetanus, poliovirus, Haemophilus influenzae type B, meningococcus C, and pneumococcus vaccines in children after hematopoietic stem cell transplantation.

BACKGROUND: There is a decrease in antibody levels after hematopoietic stem cell transplant (HSCT), and such patients may be at increased risk of acquiring vaccine-preventable infection. A simple and validated revaccination schedule is required. The aim of this study was to evaluate the immunogenicity of a revaccination schedule for pediatric HSCT recipients. METHODS: Thirty-eight children (age, 1-18 years) who had undergone autologous or allogeneic HSCT for malignant diseases were recruited. All children received vaccinations in accordance with a predefined schedule. Antibody concentrations were measured before and 2-4 weeks after vaccination against tetanus; Haemophilus influenzae type b (Hib); meningococcus C; measles; poliovirus serotypes 1, 2, and 3; and 9 pneumococcus serotypes. RESULTS: Before vaccination, protective antibody levels were found for tetanus in 95% of patients (geometric mean concentration [GMC], 0.07 IU/mL; 95% CI, 0.05-0.1 IU/mL), for Hib in 63% (GMC, 0.34 microg/mL; 95% CI, 0.21-0.57 microg/mL), for measles in 60% (GMC, 102 mIU/mL; 95% CI, 41-253 mIU/mL), for meningococcus C in 11% (geometric mean titer [GMT], 1:4; 95% CI, 1:2-1:8.4), for all 3 poliovirus serotypes in 29%, and for all 9 pneumococcal serotypes in 0%. Vaccination resulted in a significant increase (P < or = .05) in antibody levels to each vaccine antigen studied, with 100% of patients achieving protection against tetanus (GMC, 2.2 IU/mL; 95% CI, 1.8-2.7 IU/mL), 100% achieving protection against Hib (GMC, 8.4 microg/mL; 95% CI, 7.6-9.3 microg/mL), 100% achieving protection against measles (GMC, 2435 mIU/mL; 95% CI, 1724-3439 mIU/mL), 100% achieving protection against meningococcus C (GMT, 1:5706; 95% CI, 1:3510-1:9272), 92% achieving protection against the 3 poliovirus serotypes, and > or = 80% achieving protection against each of the heptavalent pneumococcal conjugate vaccine-associated serotypes. No factors relevant to age, underlying disease, or treatment type were found to significantly influence responses. CONCLUSION: Revaccination of pediatric HSCT recipients in accordance with this revaccination schedule provides a high level of protection against these vaccine-preventable diseases.

Revaccination of children after completion of standard chemotherapy for acute leukemia.

BACKGROUND: After the treatment of patients with acute leukemia, there is a decrease in vaccine-specific antibody and an increased susceptibility to certain vaccine-preventable diseases. A simple revaccination schedule is warranted. METHOD: Fifty-nine children (age, 1-18 years) who had completed standard chemotherapy in accordance with Medical Research Council of United Kingdom protocols were recruited. All children received a single dose of Haemophilus influenzae type b (Hib), tetanus, diphtheria, acellular pertussis, meningococcus C, polio, measles, mumps, and rubella vaccines > or = 6 months after completion of treatment. Antibody concentrations were measured before vaccination and 2-4 weeks and 12 months after vaccination. RESULTS: Prevaccination antibody levels were protective for all patients for tetanus (geometric mean concentration [GMC], 0.13 IU/mL; 95% CI, 0.1-0.17 IU/mL), for 87% for Hib (GMC, 0.5 microg/mL; 95% CI, 0.37-0.74 microg/mL), for 71% for measles (GMC, 301 mIU/mL; 95% CI, 163-557 mIU/mL), for 12% for meningococcus C (geometric mean titer [GMT], 1:2.9; 95% CI, 1:2.2 to 1:3.9), and for 11% for all 3 poliovirus serotypes. Revaccination resulted in a significant increase in levels of antibody to each vaccine antigen, with 100% of patients achieving optimal antitetanus antibody concentrations (defined as > 0.1 IU/mL; 1.5 IU/mL; 95% CI, 1.1-2.1 IU/mL), 93% achieving optimal antibody concentrations to Hib (defined as > 1.0 microg/mL; 6.5 microg/mL; 95% CI, 5.1-8.2 microg/mL), 94% achieving optimal antibody concentrations to measles (defined as > or = 120 mIU/mL; 2720 mIU/mL; 95% CI, 1423-5198 mIU/mL), 96% achieving optimal antibody concentrations to meningococcus C (defined as > or = 1:8; 1:1000; 95% CI, 1:483-1:2064), and 85% achieving optimal antibody concentrations to all the 3 poliovirus serotypes (defined as > or = 1:8). For the majority of subjects, protection persisted for at least 12 months after vaccination. CONCLUSION: Revaccination of children after standard chemotherapy is important, and protection can be achieved in the majority of these children using a simple schedule of 1 vaccine dose at 6 months after completion of leukemia therapy.

Haemopoietic progenitor cell transplantation in patients with previous history of invasive fungal infection.

The aim of this retrospective study conducted between H.U. Marques de Valdecilla (Spain) and the Royal Marsden NHS Trust (UK) was to analyse the outcome of patients who underwent haemopoietic progenitor cell transplantation (HPCT) after a previous history of Invasive fungal infections (IFI). This study includes 27 patients (15 autologous, 12 allogeneic). The diagnosis of IFI was microbiologically proven in 21 cases and only radiologically in six. Pre-HPCT treatment included intravenous antifungals in all and surgical excision in eight cases. All patients received post-HPCT antifungal prophylaxis. Median time from diagnosis of IFI to HPCT was 131 days. At median follow-up of 193 days, three patients (two allogeneic, one autologous) had relapse of IFI resulting in death in all cases. One of them had received TBI and two were receiving treatment for graft versus host disease. Each patient was receiving a different form of prophylaxis. Overall, seven patients are alive and disease-free. Ten patients died from disease progression and 10 from transplant-related toxicity, including IFI. In our experience, the risk of post-HPCT reactivation of a previous IFI is low (11%), so IFI should not be an absolute contraindication for HPCT. The combination of aggressive antifungal treatment for IFI and antifungal prophylaxis throughout HPCT reduces the probability of reactivation.

Cytomegalovirus reactivation in pediatric hemopoietic progenitors transplant: a retrospective study on the risk factors and the efficacy of treatment.

Cytomegalovirus (CMV) disease is an important infectious complication after allogeneic hemopoietic progenitors transplant (HPT), but few data are available in children. To investigate the factors influencing CMV reactivation, subsequent relapses of positive antigenemia, and the development of organ disease in children, the authors retrospectively analyzed 108 children who received allogeneic HPT for malignant conditions at one center. Of these, 41 were CMV serology positive (donor or recipient) before HPT. All those with CMV-positive serology received high-dose acyclovir in conjunction with weekly CMV phosphoprotein-pp65 antigen monitoring of the peripheral blood during the first 3 months. Those with CMV reactivation (positive antigenemia) received preemptive treatment with ganciclovir and/or foscarnet to prevent CMV disease. The incidence of positive antigenemia in this cohort was 41.5% at a mean of 44 +/- 31.6 days after HPT. Two patients (4.9%) subsequently developed late CMV disease. Recipient CMV status was significantly (P = 0.0001) more relevant to reactivation than donor status. Reactivations were significantly more common in single recipient seropositive than double (donor and recipient) positive pairs (P = 0.05). Reactivations were significantly more common in recipients of unrelated donor grafts than matched-related donor grafts (P = 0.025). Reactivations also occurred significantly more in T-cell-depleted graft recipients (P = 0.004) than recipients of unmanipulated grafts. The subsequent development of disease was more common in a CMV-seropositive recipient receiving a CMV-seronegative, T-cell-depleted, unrelated donor graft, and after transplantation receiving treatment for acute graft-versus-host disease. Patients with identified high risk factors for CMV reactivation and disease should be monitored by CMV PCR, and early preemptive treatment should be instigated to prevent the development of disease.

Varicella-zoster reactivation in a patient receiving routine revaccinations after an allogeneic hemopoietic progenitors transplant.

Primary varicella-zoster virus (VZV) infection and herpes zoster are important infectious complications after an allogeneic hemopoietic progenitors transplant (HPT). The authors describe a girl with second relapse of acute lymphoblastic leukemia who received an HPT at age 13 years. Two years after the HPT she started a revaccination program of routine childhood vaccines. With each course of vaccines she developed herpes zoster of the C6 dermatome, initially with the rash and later zoster sine herpete. The vaccinations appear to have triggered VZV reactivation by vaccine-induced immunomodulation in this HPT recipient.

Favorable effect on acute and chronic graft-versus-host disease with cyclophosphamide and in vivo anti-CD52 monoclonal antibodies for marrow transplantation from HLA-identical sibling donors for acquired aplastic anemia.

Between August 1989 and November 2003, 33 patients at our center with acquired aplastic anemia underwent bone marrow transplantation (BMT) from HLA-identical sibling donors with cyclophosphamide and in vivo anti-CD52 monoclonal antibodies (MoAb) for conditioning. The median age at BMT was 17 years (range, 4-46 years). Before BMT, 58% were heavily transfused (>50 transfusions), and 42% had previously experienced treatment failure with antithymocyte globulin-based immunosuppressive therapy. Unmanipulated bone marrow was used as the source of stem cells in all patients except 1. Graft-versus-host disease (GVHD) prophylaxis was with cyclosporine alone in 19 (58%) patients; 14 received anti-CD52 MoAb in addition to cyclosporine. The conditioning regimen was well tolerated without significant acute toxicity. Graft failure was seen in 8 patients (primary, n = 4; secondary, n = 4). Of those whose grafts failed, 4 survived long-term (complete autologous recovery, n = 2; rescue with previously stored marrow, n = 1; second allograft, n = 1). The cumulative incidence of graft failure and grade II to IV acute and chronic GVHD was 24%, 14%, and 4%, respectively. None developed extensive chronic GVHD. With a median follow-up of 59 months, the 5-year survival was 81% (95% confidence interval, 68%-96%). No unexpected early or late infectious or noninfectious complications were observed. We conclude that the conditioning regimen containing cyclophosphamide and anti-CD52 MoAb is well tolerated and effective for acquired aplastic anemia with HLA-matched sibling donors. The favorable effect on the incidence and severity of GVHD is noteworthy in this study and warrants further investigation.

High-dose granulocyte colony-stimulating factor mobilizes a higher proportion of early CD34(+) CD33(-) hemopoietic progenitors in children receiving treatment for solid tumors.

A relationship between dose of granulocyte colony-stimulating factor (G-CSF) and maturational stage of the progenitors mobilized in healthy adult donors has been suggested. In this study we characterize the progenitors mobilized by 2 different dosages of G-CSF in children receiving autologous grafts after intensive treatment for solid tumors.