On November 2 2016 the eleventh edition of the CONGres was held at Amsterdam Science Park. The theme of the conference was ‘Senses: biology makes sense’.
Dr. Sanne Boesveldt
Dr. Martijn Agterberg
Prof. Dr. Ir. Joop van Loon
Dr. Martine Maan
Prof. Dr. Pieter Medendorp
Prof. Dr. Linda Barlow
Dr. Sanne Boesveldt, University of Wageningen
The importance of the senses
By means of our five senses we perceive the world around us. We can see and smell a beautiful bouquet of flowers. When we touch and pet our cat we can hear him purr. And we can taste the food we eat. Not only are our different senses crucial for our survival and guiding our behavior, they also create tremendous pleasure in our lives. When it comes to eating behavior, all our senses play a role in food and flavor perception, most importantly smell and taste. Taste can function as nutrient-sensing system during consumption, while smell is crucial in the anticipation of food. Unfortunately, many people also suffer from loss of smell and/or taste, and unlike sight or hearing, this cannot be easily treated or compensated for. In 2015, we opened a Smell and Taste Center, in order to gain more insight into the (patho)physiology of these sensory systems, and to better diagnose, and potentially treat these patients.
Dr. Martijn Agterberg, Radboud University Nijmegen
Hearing & Implants, the importance of having a second ear
In the Netherlands every year approximately 250 children are diagnosed with congenital hearing disorders. For children with bilateral hearing disorders the treatment is well standardized. Completely deaf children are bilaterally implanted with a cochlear implant and children with bilateral conductive hearing loss can hear by means of bone-conduction devices.
A cochlear implant (CI) consists of an electrode array, implanted in the cochlea, and an external processor, transmitting the sounds to electrical pulse trains. With a CI the auditory nerve is stimulated directly, bypassing the damaged sensory cells (hair cells). The CI is the most successful neural prosthesis. Manny children perform well during education in regular classes, and the best performers can even communicate by spoken language over a phone.
Other treatment options are a bone-conduction device or a middle ear implant. In this lecture the success of these implants will be discussed in relation to the plasticity and organization of the auditory system. It will be explained how these implants work and how technological developments result in a continuously increasing number of treatment options.
For children with unilateral hearing loss treatment is more complex than for completely deaf children. Children with unilateral hearing loss can still benefit from the remarkable capacities of one normal functioning ear. However, binaural cues are not accessible, resulting in problems with understanding of speech in noisy situations (school) and in problems with localization of sounds (traffic, safety). Binaural hearing refers to the proper integration of interaural differences in time (ITDs) and level (ILDs).
The methods to investigate the improvement of hearing when listening with a hearing implant are explained and the limitations of hearing with implants are emphasised. Focus will be on the improvement of directional hearing when listening with either a CI or a bone-conduction implant.
Prof. Dr. Ir. Joop van Loon, Wageningen Universiteit
Insect taste and smell: basic science for the design of behavioural interference
Mosquitoes smell human and animal skin odours consisting of hundreds of volatile chemicals and display preferences among those odours. Electrophysiological studies of the olfactory organs of the malaria mosquito have resulted in the detailed characterisation of olfactory neuron response types. By a systematic approach of tightly coordinating analytical chemistry of volatile blends produced by bacteria on the human skin, electrophysiology and behavioural assays in olfactometers we have recently succeeded in formulating a synthetic volatile blend that is highly attractive to gravid mosquito females and has shown to be competitive with the attraction to human hosts under field conditions in Africa. By combining an attractant blend and a spatial repellent we demonstrated proof-of-principle for the feasibility of a push-pull approach in behavioural disruption of mosquito host-seeking behaviour that holds promise for future insect vector control programmes.
Dr. Martine Maan, Rijksuniversiteit Groningen
Sensory perception and the origin of species
Sensory perception mediates many biological functions that affect both survival and reproduction. Consequently, natural selection has generated a great diversity of sensory systems among animals, in response to the different sensory environments they inhabit. In my talk, I will discuss the idea that sensory adaptation can contribute to speciation: exploitation of alternative sensory niches can be a starting point for the evolution of new species. I will present some of our ongoing work in African cichlid fish, in which we explore how visual adaptation to different underwater light conditions could initiate species divergence.
Prof. Dr. Pieter Medendorp, Donders Instituut Nijmegen
Neuroscience of sensation and action
Sensation and action can be described as two sides of the same coin. The sensory system has to estimate the state of the world (e.g., where and what are interesting objects) and body (e.g., where are my hands), while the motor system is concerned with prospective control, i.e. generating the motor commands needed to acquire a particular task. Recent insights based on optimality principles suggest that both the estimation and control problem are intertwined in many ways, in line with neurobiological findings. In my talk, I will present various research approaches that can be used and findings that have been obtained about the brain’s computations that make us perceive and act.
Prof. Dr. Linda Barlow, University of Colorado
Maintaining a sense of taste
Taste is a fundamental sense and is crucial for human health. Like our other primary senses, we consider our ability to appreciate sweet, sour, salty, bitter and umami tastes to be relatively constant, even though taste bud cells that transduce these stimuli are renewed rapidly and regularly. The importance of the sense of taste is particularly evident for cancer patients receiving a range of radiation and chemotherapies, as these individuals often experience significant taste loss or dysfunction, and as a result, a significantly diminished quality of life. In the past decade, understanding of cellular and molecular mechanisms governing taste bud renewal has expanded significantly. In numerous renewing epithelia, the Hedgehog (HH) and Wnt/beta-catenin signaling pathways are key regulators of homeostasis. Using an arsenal of multi-allelic mouse models, we have found that HH and Wnt signaling also control taste bud cell renewal. Specifically, Wnt signaling is required to maintain taste cell renewal and is key for continued proliferation of taste progenitor cells, while the level of Wnt/beta-catenin signal impacts the fate of new cells generated from the progenitor population. Our working model of HH pathway function is that it promotes taste bud cell differentiation from progenitors, but does not regulate progenitor proliferation. Going forward, it will be important to understand how these pathways function together, as well as how these may be impacted by cancer therapies.